VxVM User's Guide

Volume Operations

Chapter 6

Introduction

The Visual Administrator performs volume operations by executing the appropriate Volume Manager commands. This chapter provides instructions on performing the following volume operations using the Visual Administrator:

The quick reference section at the end of this chapter provides information on the Visual Administrator volume operation menus and forms.

Creating a Volume

Volumes need to be created in order to take advantage of the Volume Manager concept of virtual disks. Once a volume exists, a file system can be placed on the volume to organize the disk space with files and directories. Alternatively, applications like databases might be used to organize data on volumes.

The creation of a volume involves the creation of plex and subdisk components. With the basic approach to volume creation, the underlying plexes and subdisks are handled automatically. You simply indicate the desired volume characteristics.

You can create various types of volumes using either the basic or the advanced approach:

Basic -- The basic approach takes information about what the user wants to accomplish and then performs the necessary underlying tasks. This approach requires only minimal input from the user, but does permit more detailed specifications. Basic operations are accessed via the Basic-Ops menu.
Advanced -- The advanced approach consists of a number of fairly complicated commands that typically require the user to specify detailed input. These commands use a "building block" approach that requires the user to have a detailed knowledge of the underlying structure and components in order to manually perform the sequences of commands necessary to accomplish a certain task. Advanced operations are accessed via the Advanced-Ops menu.

Volumes can be created with various layout types:

Simple -- A concatenated volume whose subdisks are arranged both sequentially and contiguously within a plex. Concatenation allows a volume to be created from multiple regions of one or more disks if there is not enough space for an entire volume on a single region of a disk.
Striped -- A volume with data spread fairly evenly across multiple disks. Stripe units are equally-sized fragments that are allocated alternately and evenly to the subdisks of a single plex. There should be at least two subdisks in a striped plex, each of which should exist on a different disk. Throughput increases with the number of disks across which a plex is striped. Striping helps to balance I/O load in cases where high traffic areas exist on certain subdisks.
RAID-5 -- A volume that uses striping to spread data fairly evenly across multiple disks in an array, and allows independent access. It also stripes parity across all the disks in the array, rather than being concentrated on a single parity disk. Each stripe contains parity stripe units and data stripe units. In comparison to the performance of striped volumes, throughput of RAID-5 volumes decreases since parity information needs to be updated each time data is written. However, in comparison to mirroring, the use of parity reduces the amount of space required.
Mirrored -- A volume with multiple plexes that duplicate the information contained in a volume. Although a volume can have a single plex, at least two are required for true mirroring (redundancy of data) to be in effect. Each of these plexes should contain disk space from different disks, in order for the redundancy to be useful.
Striped and Mirrored -- A volume with a striped plex and another plex that mirrors the striped one. This requires at least two disks for striping and one or more other disks for mirroring (depending on whether the plex is simple or striped). A striped and mirrored volume is advantageous because it both spreads data across multiple disks and provides redundancy of data.

Creating a Simple Volume

You can create a simple volume using either a basic approach or an advanced approach.

Basic Approach

Create a simple, concatenated volume using the basic approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Optionally designate a disk to be used for the new volume. Ensure that the disk has sufficient free space to accommodate the desired length of the new volume by clicking the RIGHT button on an unobscured portion of that disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. For more information on the VM disk properties form, refer to on-line help or Table 28, in Chapter 4.
: If there is sufficient free space, select the disk by clicking the LEFT button on its icon. If no disks are selected, disks with sufficient free space are automatically used.
: 3. From the Basic-Ops menu, select Volume Operations, then Create. A sub-menu listing basic volume types appears.
: 4. Select Simple. The Simple Volume/FS Create form appears (see Figure 63). This form creates a concatenated volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume; the file system fields are greyed out because the default is not to add a file system to the volume.

Figure 63 Simple Volume/FS Create Form

: 5. Complete the Simple Volume/FS Create form.For detailed information on this form, refer to on-line help or Table 46.
: 6. When the form is properly completed, select Apply to activate the volume (and optional file system) creation.

A new volume icon appears. Since this is a simple, concatenated volume, it contains a single plex. If a file system exists and is mounted, it is represented by the mount point, which appears below the new volume.

Figure 64 illustrates a simple, concatenated volume.

Figure 64 Simple Volume

Advanced Approach

Create a simple, concatenated volume using the advanced approach as follows:

1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).

2. Designate the disk on which to create the subdisk. Ensure that the disk has sufficient free space to accommodate the desired length of the new volume by clicking the RIGHT button on an unobscured portion of that disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. If there is sufficient free space, select the disk by clicking the LEFT button on its icon. For more information on the VM disk properties form, refer to on-line help or Table 28 in Chapter 4.

3. From the Advanced-Ops menu, select Subdisk, then Create. The Subdisk Create form appears. This form establishes the parameters for the subdisk. Some of the fields already contain default values and others are optional; only the subdisk length is required.

4. Complete the Subdisk Create form, entering the subdisk length and optionally altering other fields.Enter the length of the subdisk to be created. If no units are specified, the number is assumed to be in sectors. This offset should not place this subdisk within the bounds of another subdisk on the disk or past the end of the disk. The maximum length of this field is 14 characters.

For more detailed information on this form, refer to on-line help or Table 58 in Chapter 8.

5. When the form is properly completed, select Apply to activate the subdisk creation. A new subdisk icon appears in the selected disk icon.

6. Drag the new subdisk icon (by pressing and continuing to hold the LEFT button) beyond the borders of its disk and into an open area of the view window. Drop the subdisk by releasing the LEFT button. The Plex Create form appears. When this form is invoked in this way, it will automatically create a new plex and associate the dragged subdisk with it. The Plex Create form establishes the parameters for the plex. Some of the fields already contain default values and others are optional. Since this is to be a concatenated (simple) volume, the layout must be set to Concatenated.

7. Complete the Plex Create form, indicating a concatenated layout and optionally altering any fields. For more detailed information on this form, refer to on-line help or Table 54 in Chapter 7.

8. When the form is properly completed, select Apply to activate both the plex creation and the association of subdisk and plex. A plex icon containing a subdisk icon appears. The fact that the subdisk icon is within the plex icon confirms their association. The length of the plex should be the same as that of the subdisk.

9. Select the new plex by clicking the LEFT button on its icon. When the plex is selected immediately prior to the creation of the volume in this way, the plex will automatically be associated with the new volume.

10. From the Advanced-Ops menu, select Volume, then Create. The Volume Create form appears. This form establishes the parameters for the volume. Some of the fields already contain default values and others are optional. Notice that the length is the same as that of the subdisk in the selected plex.

11. Complete the Volume Create form, optionally altering any fields. For more detailed information on this form, refer to on-line help or Table 51.

12. When the form is properly completed, select Apply to activate both the volume creation and the association of plex and volume. A volume icon appears around the plex and its associated subdisk. The fact that the plex icon is within the volume icon confirms their association.

13. Initialize the volume:

: a. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: b. Select the volume that is to be initialized by clicking the LEFT button on its icon.
: c. From the Advanced-Ops menu, select Volume, then Initialize. A sub-menu appears and offers the following choices for the volume initialization: Active, Enable, Clean, or Zero.
: d. Select Active (this is recommended for most circumstances).

Creating a Striped Volume

You can create a striped volume using either the basic approach or the advanced approach.

Basic Approach

Create a striped volume using the basic approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Optionally designate at least two disks to be used for the new volume. These disks must belong to the same disk group. Ensure that the disks have sufficient free space to accommodate their portion of the desired length of the new volume by clicking the RIGHT button on an unobscured portion of each disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. For more detailed information on this form, refer to on-line help or Table 28 in Chapter 4.
: If there is sufficient free space, select the disks by clicking the MIDDLE button on their icons. If no disks are selected, disks with sufficient free space are automatically used.
: 3. From the Basic-Ops menu, select Volume Operations, then Create. A sub-menu listing basic volume types appears.
: 4. Select Striped. The Striped Volume/FS Create form appears (see Figure 65). This form creates a striped volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume; the file system fields are greyed out because the default is not to add a file system to the volume.

Figure 65 Striped Volume/FS Create Form

: 5. Complete the Striped Volume/FS Create form. For detailed information, refer to on-line help or Table 47.
: 6. When the form is properly completed, select Apply to activate the volume and file system creation.

A new volume icon appears. Since this is a striped volume, it contains a single plex and multiple subdisks. Note that there are gaps between the subdisks of the plex to indicate that it is striped. If a file system exists and is mounted, it is represented by the mount point, which appears below the new volume.

Figure 66 shows a striped volume.

Figure 66 Striped Volume

Advanced Approach

When creating a striped volume, at least two disks must be selected across which to stripe the data on the volume's plex.

Create a striped volume with two subdisks on different disks as follows:

1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).

2. Designate the disk on which to create the first subdisk. Ensure that the disk has sufficient free space to accommodate the desired length of the new volume by clicking the RIGHT button on an unobscured portion of that disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. If there is sufficient free space, select the disk by clicking the LEFT button on its icon. For more detailed information on this form, refer to on-line help or Table 28 in Chapter 4.

4. Complete the Subdisk Create form, entering the subdisk length and optionally altering other fields. For detailed information on this form, refer to on-line help or Table 58 in Chapter 8.

5. When the form is properly completed, select Apply to activate the subdisk creation. A new subdisk icon appears in the selected disk icon.

6. Repeat the previous steps to select another disk in this disk group and create a subdisk of the same length as the first one.

7. Select both of the new subdisks by clicking the MIDDLE button on their icons.

8. From the Advanced-Ops menu, select Plex, then Create. The Plex Create form appears. When this form is invoked while subdisks are selected, it will automatically create a new plex and associate the selected subdisks with it. The Plex Create form establishes the parameters for the plex. Some of the fields already contain default values and others are optional. The number of stripes is set to the number of selected subdisks (two). Since this is to be a striped volume, the layout must be set to Striped and the stripe unit size must be entered.

9. Complete the Plex Create form, indicating stripe information and optionally altering any other fields.For detailed information on this form, refer to on-line help or Table 54 in Chapter 7.

10. When the form is properly completed, select Apply to activate both the plex creation and the association of subdisks and plex. A plex icon containing both subdisk icons appears. The fact that the subdisk icons are within the plex icon confirms their association.

11. Select the plex by clicking the LEFT button on its icon. When the plex is selected immediately prior to the creation of the volume in this way, it will automatically be associated with the new volume.

12. From the Advanced-Ops menu, select Volume, then Create. The Volume Create form appears. This form establishes the parameters for the volume. Some of the fields already contain default values and others are optional. Notice that the length is the combined length of the subdisks in the selected plex.

13. Complete the Volume Create form, optionally altering any fields. For detailed information on this form, refer to on-line help or Table 51.

14. When the form is properly completed, select Apply to activate both the volume creation and the association of plexes and volume. A volume icon appears around the plex and its associated subdisks. The fact that the plex icon is within the volume icon confirms their association.

15. Initialize the volume:

: a. Select the volume that is to be initialized by clicking the LEFT button on its icon.
: b. From the Advanced-Ops menu, select Volume, then Initialize. A sub-menu appears and offers four choices for the volume initialization: Active, Enable, Clean, or Zero.
: c. Select Active (this is recommended for most circumstances).

Creating a RAID-5 Volume

Create a RAID-5 volume using the basic approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Optionally, designate at least three disks (ideally, four or more) to be used for the new volume. These disks must belong to the same disk group. Ensure that the disks have sufficient free space to accommodate their portion of the desired length of the new volume by clicking the RIGHT button on an unobscured portion of each disk icon to access its properties form, then checking the value in the Maximum free space field.
: If there is sufficient free space, select the disks by clicking the MIDDLE button on their icons. If no disks are selected, disks with sufficient free space are automatically used.
: 3. From the Basic-Ops menu, select Volume Operations, then Create. A sub-menu listing basic volume types appears.
: 4. Select RAID-5. The RAID-5 Volume/FS Create form appears (see Figure 67). This form creates a RAID-5 volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume. The file system fields are greyed out because the default is to add a file system to the volume only when you access this menu via the Basic Ops, File Systems Operations menu.

Figure 67 RAID-5 Volume/FS Create Form

: 5. Complete the RAID-5 Volume/FS Create form.For detailed information on this form, refer to on-line help or Table 48.
: 6. When the form is properly completed, select Apply to activate the volume and file system creation.

A new volume icon appears. Since this is a RAID-5 volume, it contains one RAID-5 plex with multiple subdisks and one log plex. Note that there are gaps between the subdisks of the RAID-5 plex to indicate that it is striped. The double outline indicates the log plex. If a file system exists and is mounted, it is represented by the mount point, which appears below the new volume.

Figure 68 shows a RAID-5 volume.

Figure 68 RAID-5 Volume

Creating a Mirrored Volume

A mirrored volume has multiple plexes that duplicate the information contained in a volume. Although a volume can have a single plex, at least two plexes on different disks are required for true mirroring (redundancy of data) to be in effect.

To create a mirrored volume, a volume must be created and then mirrored. The mirror layout can be simple or striped. The number of available disks must be sufficient to accommodate the layout type of both the existing volume and the mirror to be added. If a striped layout is desired, at least two disks other than those already in use by the volume must be available because one disk is required per stripe.

You can create a mirrored volume using either the basic approach or the advanced approach.

Basic Approach

Create a mirrored volume using the basic approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Create a simple volume, as described in a previous section.
: 3. Select the new volume to which a mirror is to be added by clicking the LEFT button on its icon.
: 4. Optionally designate at least one disk (not already being used by the volume itself) to be used for the new mirror. If the mirror is to be striped, at least two disks other than those already in use by the volume must be selected; if the mirror is to be simple, only one disk is selected. These disks must belong to the same disk group. Ensure that the disks have sufficient free space to accommodate their portion of the desired length of the new volume by clicking the RIGHT button on an unobscured portion of each disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. For details on this form, refer to Table 28 in Chapter 4.
: If there is sufficient free space, select the disks by clicking the MIDDLE button on their icons. If no disks are selected, disks with sufficient free space are automatically used.
: 5. From the Basic-Ops menu, select Volume Operations, then Add Mirror. A sub-menu listing mirror layout options appears.
: 6. Select either Simple or Striped, depending on the desired mirror layout.

The volume's icon expands visibly and a new mirror appears within its borders. The new mirror layout depends on what was specified during the Add Mirror operation.

Advanced Approach

When creating a mirrored volume, at least two plexes must be created on at least two disks. Both plexes must then be associated with the same volume.

Create a mirrored volume with two plexes, each containing a single subdisk as follows:

1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).

2. Designate the disk on which to create the first subdisk. Ensure that the disk has sufficient free space to accommodate the desired length of the new volume by clicking the RIGHT button on an unobscured portion of that disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. If there is sufficient free space, select the disk by clicking the LEFT button on its icon. For details on this form, refer to Table 28 in Chapter 4.

4. Complete the Subdisk Create form, entering the subdisk length and optionally altering other fields.For details on this form, refer to on-line help or Table 58 in Chapter 8.

5. When the form is properly completed, select Apply to activate the subdisk creation. A new subdisk icon appears in the selected disk icon.

The Plex Create form appears. When this form is invoked in this way, it will automatically create a new plex and associate the dragged subdisk with it. This form establishes the parameters for the plex. Some of the fields already contain default values and others are optional. Since this volume is to contain two concatenated (simple) plexes for mirroring, the layout must be set to Concatenated.

7. Complete the Plex Create form, indicating a concatenated layout and optionally altering any other fields. For details on this form, refer to on-line help or Table 54 in Chapter 7.

9. Repeat the previous steps to select another disk in this disk group, create a subdisk of the same length as the first one on that disk, create a plex of the same type as the first, and associate the second subdisk with the second plex.

10. Select both plexes by clicking the MIDDLE button on their icons. When the plexes are selected immediately prior to the creation of the volume in this way, they will automatically be associated with the new volume.

11. From the Advanced-Ops menu, select Volume, then Create. The Volume Create form appears. This form establishes the parameters for the volume. Some of the fields already contain default values and others are optional. Notice that the length is the same as that of the subdisks in the selected plexes.

12. Complete the Volume Create form, optionally altering any fields. For details on this form, refer to on-line help or Table 51.

13. When the form is properly completed, select Apply to activate both the volume creation and the association of plexes and volume. A volume icon appears around both plexes and their associated subdisks. The plexes are side-by-side in the volume, to illustrate that they are mirrored. The fact that both plex icons are within the volume icon confirms their association.

14. Initialize the volume:

: a. To initialize the new volume, click the LEFT button on its icon.
: b. From the Advanced-Ops menu, select Volume, then Initialize. A sub-menu appears and offers four choices for the volume initialization: Active, Enable, Clean, or Zero.
: c. Select Active (this is recommended for most circumstances).

Creating a Striped and Mirrored Volume

A striped and mirrored volume is advantageous because it both spreads data across multiple disks and provides redundancy of data.

Although there is currently no menu item for creating a volume that is both striped and mirrored, it is possible to do so. This is done by creating a striped volume and then adding a mirror (in the form of either a simple or striped plex) to that volume.

The number of available disks must be sufficient to accommodate the layout type of both the existing volume and the mirror to be added. At least three disks are required in order to create a striped, mirrored volume. The striped plex requires two disks (one per stripe); the plex that acts as the mirror must occupy a third disk if it is simple or a third and fourth disk if it is also striped. If any stripes or mirrors occupy the same disk, the striping and mirroring will not be effective.

You can create a striped and mirrored volume using either a basic approach or an advanced approach.

Basic Approach

Create a striped and mirrored volume using the basic approach as follows:

: 1. Follow the steps for creating a striped volume, as described previously.
: 2. Select the new volume to which a mirror is to be added by clicking the LEFT button on its icon.
: 3. Optionally designate at least one disk (not already being used by the volume itself) to be used for the new mirror. If the mirror is to be striped, at least two disks other than those already in use by the volume must be selected; if the mirror is to be simple, only one disk is selected. These disks must belong to the same disk group. Ensure that the disks have sufficient free space to accommodate their portion of the desired length of the new volume by clicking the RIGHT button on an unobscured portion of each disk icon to access its VM disks properties form, then checking the value in the Maximum free space field. For details on this form, refer to Table 28 in Chapter 4.
: If there is sufficient free space, select the disks by clicking the MIDDLE button on their icons. If no disks are selected, disks with sufficient free space are automatically used.
: 4. From the Basic-Ops menu, select Volume Operations, then Add Mirror. A sub-menu listing mirror layout options appears.
: 5. Select either Simple or Striped, depending on the desired mirror layout. The striped volume's icon expands visibly and a new mirror appears within its borders. The new mirror layout depends on what was specified during the Add Mirror operation.

Figure 69 illustrates a striped volume with a simple mirror.

Figure 69 Striped and Mirrored Volume

Advanced Approach

The simplest method is to create a striped volume and then add a mirror to that volume. Since a striped volume is being mirrored, it is preferable for the mirror layout to be striped in order to maintain the advantages of striping. At least four disks are required in order to create a striped volume with a striped mirror; the original striped plex requires two disks and the plex that acts as a striped mirror requires an additional two disks for mirroring to be effective. If only three disks are available, a simple mirror can be added instead (although this causes some performance drawbacks).

Create a striped and mirrored volume as follows:

1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).

2. Follow the steps for creating a striped volume, as described in the previous section.

3. Designate a third disk on which to create the first subdisk for the striped mirror. Projection can be used to ensure that the third disk is not currently being used by the striped volume's subdisks (by pressing Shift-RIGHT on the striped volume's icon and observing which disks now contain highlighted subdisks). The disk should have sufficient space to accommodate a subdisk as long as the subdisk length in the striped volume. If there is sufficient free space, select the disk by clicking the LEFT button on its icon.

4. From the Advanced-Ops menu, select Subdisk, then Create. The Subdisk Create form appears. This form establishes the parameters for the subdisk. Some of the fields already contain default values and others are optional; only the subdisk length is required.

5. Complete the Subdisk Create form, entering the subdisk length (that matches that of an existing subdisk in the striped volume) and optionally altering other fields. For details on this form, refer to on-line help or Table 58 in Chapter 8.

6. When the form is properly completed, select Apply to activate the subdisk creation. A new subdisk icon appears in the selected disk icon.

7. Create an identically-sized subdisk on a fourth disk. Using the LEFT button, drag and drop the newly-created subdisk icon onto a disk icon containing sufficient space to accommodate a subdisk of the same length. Make sure the disk is not already in use by the striped volume or the selected subdisk.

A dialog box appears to announce that the dragged subdisk was not associated and that Visual Administrator has therefore created a new subdisk rather than moving one. Select the Continue button to proceed. A new subdisk icon appears on its targeted disk.

8. Select both of the new subdisks by clicking the MIDDLE button on their icons.

9. From the Advanced-Ops menu, select Plex, then Create. The Plex Create form appears. This form establishes the parameters for the plex. Some of the fields already contain default values and others are optional. The number of stripes is set to the number of selected subdisks (two). For a striped plex, the layout must be set to Striped.

10. Complete the Plex Create form, indicating stripe information and optionally altering any other fields. For details on this form, refer to on-line help or Table 54 in Chapter 7.

11. When the form is properly completed, select Apply to activate both the plex creation and the association of subdisk and plex. A plex icon containing two subdisk icons appears. The fact that the subdisk icons are within the plex icon confirms their association. The length of the plex should be the same as that of the volume to be mirrored.

12. The new plex icon can now be associated with the striped volume, thereby putting mirroring into effect. Drag and drop the new plex icon onto the striped volume icon. Position the plex so that the pointer is directly over an unobscured portion of the volume icon. The striped volume's icon expands visibly and the mirror appears within its borders.

13. Initialize the volume:

: a. Select the volume that is to be initialized by clicking the LEFT button on its icon.
: b. From the Advanced-Ops menu, select Volume, then Initialize. A sub-menu appears and offers four choices for the volume initialization: Active, Enable, Clean, or Zero.
: c. Select Active (this is recommended for most circumstances).

Removing a Volume

Volumes may be removed when they are no longer needed or when the disk space that they occupy needs to be reused.

The removal of a volume involves the removal of plex and subdisk components. With the basic approach to volume removal, the underlying plexes and subdisks are handled automatically. You simply indicate which volume is to be removed; the volume and its components are then removed and the disk space set aside for that volume is de-allocated. A volume must be selected for this operation to succeed.

CAUTION! This is a permanent operation and cannot be undone. If completed, it will be difficult or impossible to retrieve the data associated with that volume. For this reason, a confirmation window is presented if the selected volume is not ready for removal.

You can remove a volume using either a basic approach or an advanced approach.

Basic Approach

Remove a volume using the basic approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the volume to be removed by clicking the LEFT button on its icon.
: 3. From the Basic-Ops menu, select Volume Operations, then Remove Volumes Recursively. If the selected volume is enabled and therefore in danger of losing valuable data, a Visual Administrator Warning window appears to announce this fact. The warning window requires input before Visual Administrator will proceed with anything. If certain that the data on the selected volume does not need to be preserved, select OK to proceed with the removal; otherwise, select Cancel to abandon the removal.

The volume disappears when the removal is complete.

Advanced Approach

When a volume is removed via the Advanced-Ops menu, its plex and subdisk components are not automatically removed; it is necessary to manually remove each of its components. It is generally not a good idea to leave the subdisks of a removed volume behind, as the space occupied by these subdisks cannot be used by the Volume Manager's free space pool until they are removed.

Note: A volume must be stopped before it can be removed. Refer to the section on stopping volumes for information on how to stop a volume.

If a volume is to be removed instantly and recursively, the easiest approach is to use the Basic-Ops menu's volume removal option. However, the following procedure describes how to manually remove a volume and some or all of its components.

Remove a volume with a single plex and subdisk as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Stop the volume, as described in the section entitled "Stopping Volumes."
: 3. Select the volume to be removed by clicking the LEFT button on its icon.
: 4. From the Advanced-Ops menu, select Volume, then Remove Volumes. The volume icon momentarily shrinks and appears next to its plex icon, then disappears entirely. The volume is now removed, but its plex and subdisk remain.

To remove multiple volumes simultaneously, follow the previous steps, but use the MIDDLE button to select multiple volumes for removal at once.

Remove a removed volume's plex as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the plex to be removed by clicking the LEFT button on its icon.
: 3. From the Advanced-Ops menu, select Plex, then Remove Plexes. The plex icon momentarily shrinks and appears next to its previous position, then disappears entirely along with the subdisk icon. The plex is now removed, but its subdisk remains on its disk and is now categorized as a free subdisk.

To remove multiple plexes simultaneously, follow the previous steps, but use the MIDDLE button to select multiple plexes for removal at once.

Remove a removed volume and plex's subdisk as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Identify the subdisk icon that formerly belonged to the removed plex and volume. If projection is set to show free subdisks (via the Projection menu), then this subdisk icon should be highlighted on its disk.
: 3. Select the subdisk to be removed by clicking the LEFT button on its icon.
: 4. From the Advanced-Ops menu, select Subdisk, then Remove Subdisks.The subdisk icon disappears, leaving a gap (or "hole") on its disk.

To remove multiple subdisks simultaneously, follow the previous steps, but use the MIDDLE button to select multiple subdisks for removal at once.

Adding a Mirror to a Volume

A volume is mirrored in order to provide redundancy of data. Each plex on a mirrored volume duplicates the information stored on that volume.

A mirror can be added to an existing volume by associating another plex (of the correct length) to the volume. The layout of the mirror to be added can be either simple or striped. The number of available disks must be sufficient to accommodate the layout type of both the existing volume and the mirror to be added.

A volume must be selected for this operation to succeed. Disks that are not already in use by the volume itself can be selected for this operation.

Add a mirror to an existing volume as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the volume to which a mirror is to be added by clicking the LEFT button on its icon.
: 3. Optionally designate at least one disk (not already being used by the volume itself) to be used for the new mirror. If the mirror is to be striped, at least two disks other than those already in use by the volume must be selected; if the mirror is to be simple, only one disk is selected. These disks must belong to the same disk group. Ensure that the disks have sufficient free space to accommodate their portion of the desired length of the new volume by clicking the RIGHT button on an unobscured portion of each disk icon to access its VM disk properties form, then checking the value in the Maximum free space field. For detailed information on this form, refer to Table 28 in Chapter 4.
: If there is sufficient free space, select the disks by clicking the MIDDLE button on their icons. If no disks are selected, disks with sufficient free space are automatically used.
: 4. From the Basic-Ops menu, select Volume Operations, then Add Mirror. A sub-menu listing mirror layout options appears.
: 5. Select either Simple or Striped, depending on the desired mirror layout.

The volume's icon expands visibly and a new mirror appears within its borders. The new mirror layout depends on what was specified during the Add Mirror operation.

Figure 70 illustrates a simple, mirrored volume.

Figure 70 Mirrored Volume

Adding a Mirror to a Root Volume

When a volume is selected for mirroring, Visual Administrator automatically checks whether that volume is a root volume (containing bootable information). If it is, a dialog box appears and asks whether to make the new mirror bootable.

Add a mirror to a root volume as follows:

: 1. Go to the View of rootdg (which is the only view that can contain a root volume).
: 2. Select the root volume to which a mirror is to be added by clicking the LEFT button on its icon. In the Visual Administrator, a root volume appears as a normal volume icon (named rootvol, by default) with a mounted file system named /.
: 3. Follow the steps for adding a mirror to a volume, as described in the previous section.
: 4. When the Visual Administrator detects that the volume to be mirrored is a root volume, a dialog box appears and asks whether to make the new mirror bootable. The response to this should be Yes so that the mirror's disk can be used for booting if the root volume's original disk fails.

If the root volume's mirror is made bootable, mirrors are also added to the volumes swapvol and standvol (but not to any other volumes that happen to have subdisks that reside on the root disk) and slicing is maintained.

Adding a Log

This operation adds a log plex containing a log subdisk to a volume. For mirrored striped or concatenated volumes, this will add a Dirty Region Log. For RAID-5, it will add a RAID-5 log.

Note: Logs are only useful for mirrored volumes or RAID-5 volumes.

Add a log as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select a simple, striped, or RAID-5 volume by clicking the LEFT button on the icon.
: 3. From the Basic-Ops menu, select Volume Operations, then Add Log.

A log associated with a subdisk will appear in the volume icon. A simple or striped DRL log subdisk or RAID-5 log can be identified by their double borders. Logs are useful in the event of disk failures.

Removing a Mirror or Log

A mirror or log can be removed recursively, which involves automatically removing any subdisks associated with that plex. Both, mirrors and logs, that are associated with volumes, and those that are not, can be removed in this way. Space formerly allocated to the removed subdisks is returned to the free space pool.

Note: The last valid mirror in a started or enabled volume cannot be removed, unless the volume is stopped before the remove operation.

Remove a mirror or log recursively as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the mirror or log to be removed by clicking the LEFT button on its icon.
: 3. From the Basic-Ops menu, select Volume Operations, then Remove Mirror or Log. The mirror or log and any associated subdisk icons disappear, indicating that these objects have been removed. Though a RAID-5 log can be removed by the same operation, it is advisable to keep at least one log associated with the RAID-5 volume to help cope with disk failures.

Resizing a Volume

An existing volume can be resized when this becomes necessary. Resizing allows a volume to be grown or shrunk according to current needs. A volume icon must be selected in order for this operation to succeed.

Note: If a vxfs file system resides on a volume, the resize operation offered through the File System Operations menu should be used to adjust both the file system and the underlying volume.

The volume size may need to be increased if a file system or application on the volume requires additional space. If new disk space is needed during the resize, it is allocated as necessary; if space becomes unused, it is added to the free space pool. When shrinking a volume, it is important to be aware that the volume may contain data that could be lost.

The Visual Administrator does not permit a volume containing a mounted file system to be shrunk via the volume resize operation offered through the Basic-Ops menu. This prevents the possibility of losing the contents of the end of a file system whose volume has been shrunk.

Note: Since the Visual Administrator cannot tell whether an unmounted file system resides on a volume, shrinking a volume with an unmounted file system may result in unrecoverable data loss.

Resizing can take one of four forms:

Increase the volume to the given length.
Increase the volume by the given length.
Reduce the volume to the given length.
Reduce the volume by the given length.

Resize a volume as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the volume whose file system is to be resized.
: 3. From the Basic-Ops menu, select Volume Operations, then Resize. The Volume Resize form appears (see Figure 71). Most of the form fields are already set to the defaults for resizing a volume.

Figure 71 Volume Resize Form

: 4. Complete the Volume Resize form. For detailed information on this form, refer to on-line help or Table 49.
: 5. When the form is properly completed, select Apply to activate the resize operation.

As the volume is resized, the corresponding volume icon may change visibly.

Preparing a Volume for Online Backup

The Visual Administrator provides access to two forms of online backup, each of which functions differently:

the VxFS snapshot approach, offered through the File System Operations menu
the Volume Manager snapshot approach, offered through the Volume Operations menu

This section focuses on the Volume Manager approach to preparing a volume for online backup. Details on the VxFS approach (which is often preferable) are available in the chapter on file system operations.

With the Volume Manager, the snapshot operation creates a new volume that is a snapshot of an existing volume. This is done by creating a mirror of the existing volume (creating and associating a plex) using disk space from the pool of free disk space. The mirror is brought up to date (this may take some time) and a separate (snapshot) volume is then created for it. The snapshot volume represents a consistent copy of the original volume at the time the snapshot was begun. The snapshot volume can be used to make a backup of the original volume at a convenient time without stopping it. After the backup is made, the snapshot volume can be removed without losing any data.

The Volume Manager uses the vxassist utility operations to handle on-line backup of volumes with minimal interruption.

The vxassist snapstart operation creates a write-only backup mirror, which is attached to and synchronized with the volume to be backed up. The amount of synchronization time depends on the size of the volume. When synchronized with the volume, the backup mirror is ready to be used as a snapshot mirror. However, it continues being updated until it is detached during the actual snapshot portion of the procedure.

The on-line backup procedure is completed by running the vxassist snapshot command on the volume with the snapshot mirror. This operation detaches the finished snapshot mirror, creates a new normal volume, and attaches the snapshot mirror to it. The snapshot then becomes a read-only volume.

The amount of time involved in creating the snapshot mirror is long in contrast to the brief amount of time that it takes to create the snapshot volume.

Creating a Snapshot

Create a snapshot of a volume using the Volume Manager approach as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the volume to be used for backup/snapshot purposes.
: 3. From the Basic-Ops menu, select Volume Operations, then Snapshot, then Snapstart. A snapshot mirror appears within the selected volume. As the snapshot mirror is updated, its icon is greyed out. This synchronization takes a variable amount of time, which could be significant (depending on the size of the selected volume).
: 4. Once the snapshot mirror is fully updated (and its icon is no longer greyed out), prepare to make the snapshot volume by optionally asking users to save files and temporarily reduce activity. It is also a good idea to sync file systems at this point.
: 5. Select the volume containing the snapshot mirror.
: 6. From the Basic-Ops menu, select Volume Operations, then Snapshot, then Snapshot again. The Snapshot form appears.
: 7. Complete the Snapshot form. For detailed information on this form, refer to on-line help or Table 50.
: 8. When the form is properly completed, select Apply to activate the snapshot operation. When the backup plex is synchronized with the mirror, the vxassist snapshot operation begins. This portion of the procedure should only take a brief amount of time. The snapshot operation detaches the finished snapshot plex, creates a new normal volume, and attaches the snapshot plex to it. As this occurs, the original volume icon returns to its former state and the backup plex moves over into the new snapshot volume (which has the name specified in the Snapshot name field of the Snapshot form). The new snapshot volume remains as a consistent copy of the selected volume at the time the snapshot was begun.
: 9. Back up the snapshot volume to tape (or some other media).
: 10. Remove the snapshot volume when it is no longer necessary, as it takes up as much space as a normal volume.

Figure 72 illustrates a volume and its snapshot.

Figure 72 Volume and Snapshot

Removing a Snapshot

Once it has served its purpose, a snapshot volume can be removed in the same way as a regular volume is removed.

Remove a snapshot volume as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Select the snapshot volume to be removed.
: 3. From the Basic-Ops menu, select Volume Operations, then Remove Volumes Recursively. The snapshot volume and its components disappear after prompting for confirmation.

Starting and Stopping Volumes

At times, it may be necessary to start or stop a volume. Starting involves enabling a disabled volume, while stopping involves disabling an enabled one. The Visual Administrator sometimes notifies you that a volume needs to be started before a desired operation can be performed.

Volumes can switch between the following states: Started, Unstartable, and Startable.

Volumes should be initialized before they are started and must have been started before they can be stopped.

Starting Volumes

A volume must be started before most operations can be performed on that volume. With the Visual Administrator, either a single volume or all volumes can be started at one time.

Start a single volume as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Before starting the volume, confirm that it is not started. To do this, access its properties form by clicking RIGHT on its icon. The Utility State field should indicate that the volume is unstartable (never been started) or startable (currently, not started).
: 3. Select the volume to be started by clicking the LEFT button on its icon.
: 4. From the Advanced-Ops menu, select Volume, then Start Volumes, and then Start. The volume icon should rewrite itself as it is being started.
: 5. Confirm that the volume has now been started by accessing its properties form again. The Utility State field should now indicate that the volume is started.

Start all volumes simultaneously as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. From the Advanced-Ops menu, select Volume, then Start Volumes, and then Start All. All volume icons that are not started should rewrite themselves as they are being started. Volumes that were already started are not affected.
: 3. Check the properties forms of any of the newly started volumes to confirm that they are indeed started.

Stopping Volumes

A volume must be stopped before some operations (such as removal of the volume itself or dissociation of its last plex) can be performed on that volume. A volume containing a mounted file system cannot be stopped. With Visual Administrator, either a single volume or all volumes can be stopped at one time.

Stop a single volume as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. Before stopping the volume, confirm that it is started. To do this, access its properties form by clicking RIGHT on its icon. The Utility State field should indicate that the volume is started.
: 3. Select the volume to be stopped by clicking the LEFT button on its icon.
: 4. From the Advanced-Ops menu, select Volume, then Stop Volumes, and then Stop. The volume icon should rewrite itself as it is being stopped.
: 5. Confirm that the volume has now been stopped by accessing its properties form again. The Utility State field should now indicate that the volume is startable.

Stop all volumes simultaneously as follows:

: 1. Go to the view window corresponding to the disk group in which you want to perform this operation (View of rootdg, by default).
: 2. From the Advanced-Ops menu, select Volume, then Stop Volumes, and then Stop All. All started volume icons should rewrite themselves as they are being stopped. Volumes that were already stopped are not affected. For details on the Volume Operations menu choices, refer to Table 45.
: 3. Check the properties forms of any of the newly stopped volumes to confirm that they are indeed startable.

Displaying and Altering Properties

The properties of the volume corresponding to a volume icon can be displayed (and potentially adjusted) in a properties form. The Volume Properties form (illustrated in Figure 73) provides detailed information about the characteristics of a particular volume.

To access the properties form for a particular volume icon:

: >>Move the pointer onto that icon and click the RIGHT button. (If the volume is under analysis, press Shift-RIGHT instead.) The Volume Properties form appears and displays details of the volume's configuration. For detailed information on this form, refer to Table 52.

Some of the displayed properties (such as the volume's name) can be altered directly through this form by editing the appropriate field(s) and then selecting the form's Apply button. Selecting the Reset button rereads the volume properties and displays the current values.

Figure 73 Volume Properties Form

Quick Reference to Volume Operations Menus and Forms

This section provides information on volume menus and forms.

Volume Menus

Both the Basic-Ops and Advanced-Ops menus provide access to volume-related menus. Most menus provide a Help selection, which provides information on items and operations contained in that menu.

**Table 45** Volume Operations Menus
Menu/Submenu Access	Description
Basic-Ops > Volume Operations > Create	Creates a volume from one or more disks. You may select one or more disks on which to create the volume (providing there is sufficient space on the disks). If no disks are specified, the Volume Manager automatically determines which disks are to be used based on available free space. From the Create menu, select the type of volume to be created from a cascading menu listing three of the basic types of volumes: Simple, Striped, or RAID-5. If a mirrored volume is desired, a simple or striped volume must be created and then mirrored using the Add Mirror option. Requirements: * Only disks in the same disk group can be selected. * Only VM disks (disks under Volume Manager control and assigned to a disk group) can be selected. * If striping is to be in effect, at least two disks are required in order for the operation to succeed. See Also: * Simple Volume/FS Create Form (Table 46) * Striped Volume/FS Create Form (Table 47) * RAID-5 Volume/FS Create Form (Table 48)
Basic-Ops > Volume Operations > Create > Simple	Creates a simple, concatenated volume whose subdisks are arranged both sequentially and contiguously within a plex (mirror).
Basic-Ops > Volume Operations > Create > Striped	Creates a volume with data spread fairly evenly across multiple disks by way of striping. Stripes are relatively small, equally-sized fragments that are allocated alternately to the subdisks of each plex.
Basic-Ops > Volume Operations > Create > RAID-5	Creates a volume that uses striping to spread data fairly evenly across multiple disks in an array, and allows independent access. It also stripes parity across all the disks in the array. Each stripe contains a parity stripe and data stripes.
Basic-Ops > Volume Operations > Remove Volumes Recursively	Removes the selected volume(s) and deallocates all of the disk space set aside for that volume. It automatically removes all underlying mirrors (plexes) and subdisks associated with the volume. This is a permanent operation and cannot be undone. If completed, it will be difficult or impossible to retrieve the data associated with that volume. For this reason, a confirmation window is presented if the selected volume is not ready for removal (i.e., started or enabled). Requirements: * At least one volume icon must be selected. * The selected volume(s) cannot contain a mounted file system.
Basic-Ops > Volume Operations > Add Mirror	Adds a mirror to the selected volume by associating a mirror (plex) of the correct length to the volume. The mirror effectively duplicates the information contained in the volume. Although a volume can have a single mirror, at least two are required for true mirroring (redundancy of data) to be in effect. From the Add Mirror menu, select the type of mirror to be added from a cascading menu listing two of the basic types of mirrors: Simple and Striped. Disks can be selected for this operation. However, the number of selected disks must be sufficient to accommodate the layout type of both the existing volume and the mirror to be added. If no disks are selected, the free space for the mirror is allocated by the Volume Manager. Note: You cannot mirror a RAID-5 volume. Requirements: * A volume icon must be selected. * For a striped mirror, at least two disks other than those already in use by the volume must be available.
Basic-Ops > Volume Operations > Add Mirror > Simple	Adds a simple, concatenated mirror whose subdisks are arranged both sequentially and contiguously.
Basic-Ops > Volume Operations > Add Mirror > Striped	Adds a mirror whose data is allocated evenly across each of its subdisks in an alternating fashion. This is accomplished with stripes, which are relatively small, equally-sized fragments that are allocated alternately to each subdisk.
Basic-Ops > Volume Operations > Add Log	Adds a log plex containing a log subdisk to a volume. For striped and concatenated volumes, this adds a Dirty Region Log (DRL). For RAID-5, this operation adds a RAID-5 log.
Basic-Ops > Volume Operations > Remove Mirror or Log	Removes the selected mirror (plex) or log, along with any associated subdisks. Requirements: * A mirror or log icon must be selected. * The last valid mirror in a started or enabled volume cannot be removed, unless the volume is stopped before the remove operation.
Basic-Ops > Volume Operations > Resize	Resizes the selected volume. The volume can be increased to, increased by, reduced to, or reduced by a given length. This involves adding or removing disk space to/from the plexes associated with the volume. If new disk space is needed during the resize, it is allocated as necessary. Any unused space is added to the free space pool. Requirements: * A volume icon must be selected. * A volume containing a mounted file system cannot be shrunk. See Also: * Volume Resize Form (Table 49)
Basic-Ops > Volume Operations > Snapshot	Backs up a volume by creating a snapshot image of that volume. This is a convenient way of performing online backup with minimal interruption. This operation invokes the Volume Manager snapshot approach, in which the snapshot operation creates a new volume that is a snapshot of an existing volume. This is done by creating a mirror of the existing volume (creating and associating a plex) using disk space from the pool of free disk space. The mirror is brought up to date (this may take some time) and a separate (snapshot) volume is then created for that mirror. The snapshot volume represents a consistent copy of the original volume at the time the snapshot was begun. The snapshot volume can be used to make a backup of the original volume without stopping it. After the backup is made, the snapshot volume can be removed without losing any data. From the Snapshot menu, a cascading menu allows you to first create the snapshot mirror and then the snapshot volume: Snapstart and Snapshot. Requirements: * A volume icon must be selected. * There must be sufficient free disk space to accommodate the snapshot volume. See Also: * Snapshot Form (Table 50)
Basic-Ops > Volume Operations > Snapshot > Snapstart	Starts the snapshot procedure by creating a snapshot mirror within the volume to be backed up. It takes a variable amount of time to update the new mirror, during which time the snapshot mirror icon is ghosted.
Basic-Ops > Volume Operations > Snapshot > Snapshot	At a convenient time (preferably after warning users to reduce activity briefly), create another volume for the snapshot mirror. This portion of the procedure should take only seconds to complete.
Basic-Ops > Volume Operations > Help	Accesses a Help window that displays information relevant to the basic volume operations.
Advanced-Ops > Volume > Create	Creates a volume. You may select one or more plexes (mirrors) to be associated with the new volume after creation. See Also: * Volume Create Form (Table 51)
Advanced-Ops > Volume > Remove Volumes	Removes the selected volume(s). If the selected volume is started, it must be stopped before it can be removed. This is a permanent operation and cannot be undone. Any plexes (mirrors) associated with the volume will be dissociated and left behind. Requirements: * At least one volume icon must be selected. * The volume must be stopped before it can be removed.
Advanced-Ops > Volume > Initialize Volumes	Initializes the selected volume(s). From the Initialize Volumes menu, select the type of initialization from a cascading menu listing four choices: Active, Enable, Clean, and Zero. Requirements: * At least one volume icon must be selected. * The selected volume cannot have been previously initialized. * The selected volume should have at least one associated plex (mirror) that is complete (or contiguous).
Advanced-Ops > Volume > Initialize Volumes > Active	Enables the selected volume and its associated plexes (mirrors), and sets the state of all associated plexes to ACTIVE.
Advanced-Ops > Volume > Initialize Volumes >Enable	Enables the selected volume and its associated plexes (mirrors), but leaves the plex states as EMPTY.
Advanced-Ops > Volume > Initialize Volumes >Clean	Sets the state for all associated plexes (mirrors) of the selected volume to CLEAN. This can be applied only under limited circumstances.
Advanced-Ops> Volume > Initialize Volumes >Zero	Enables the selected volume and its associated plexes (mirrors), then write zeroes over the entire volume. After the operation completes, all associated plexes are set to ACTIVE, assuming that there are no I/O errors.
Advanced-Ops > Volume > Start Volumes	Starts the selected volume(s). A volume must be started before it can be accessed. From the Start volumes menu, a cascading menu allows you to indicate whether all volumes or just those selected should be started. Requirements: * At least one volume icon must be selected for the Start operation. No volume icons need to be selected for the Start All operation. * A volume must be initialized before it can be started.
Advanced-Ops > Volume > Start Volumes > Start	Starts the selected volume, which must be startable.
Advanced-Ops > Volume > Start Volumes > Start All	Starts all volumes in this disk group that can be started.
Advanced-Ops > Volume > Stop Volumes	Stops the selected volume(s). A stopped volume is inaccessible. From the Stop volumes menu, a cascading menu allows you to indicate whether all volumes or just those selected should be stopped Requirements: * At least one volume icon must be selected for the Stop operation. No volume icons need to be selected for the Stop All operation. * A volume must be started before it can be stopped. * A volume that is in use or contains a mounted file system cannot be stopped.
Advanced-Ops > Volume > Stop Volumes> Stop	Stops the selected volume.
Advanced-Ops > Volume > Stop Volumes > Stop All	Stops all volumes in this disk group.
Advanced-Ops > Volume > Resynchronize Volumes	Brings all plexes (mirrors) within the selected volume(s) up to date. Any plexes that are inconsistent are resynchronized to contain consistent data. Depending on how current the plexes are, this operation may take some time. Requirements: * At least one volume icon must be selected. * The selected volume(s) must be started.
Advanced-Ops > Volume > Set to Maint State	Sets the state of the selected volume(s) to a maintenance state. Refer to the `vxvol`(1M) manual page for information on the maintenance state. Requirements: * At least one volume icon must be selected.
Advanced-Ops > Volume > Help	Accesses a Help window that displays information relevant to the basic volume operations.

Volume Forms

Some volume operations result in the appearance of forms, which must be completed in order for that operation to proceed. Most forms provide a Help button, which contains information relevant to the fields and other aspects of that particular form.

Some form fields are required, while others are not. Fields in these forms are read/write unless listed as read only.

Note: If vxfs is not installed when vxva is started, form fields corresponding to options that are specific to vxfs file systems are either excluded from forms or greyed out.

Simple Volume/FS Create Form

This form creates a concatenated volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume; the file system fields are greyed out because the default is not to add a file system to the volume.

**Table 46** Simple Volume/FS Create Form
Field	Description
Volume name:	Either use the default or enter a different name for the volume to be created. The name must be unique within this disk group. The maximum length of this field is 31 characters.
Volume size:	Enter the desired volume size. The size should be entered as a number followed immediately by the letter `k`, `m`, `s`, or `g` to indicate kilobytes, megabytes, sectors, or gigabytes, respectively. If no unit is specified, the default is sectors. The volume size should be less than or equal to the available free space of the disks. If you click on the Maxsize button, the Volume Manager calculates and displays the maximum volume size possible with this form's current settings. If no disks are selected, the calculation includes available space on all disks in the disk group. Otherwise, the calculation includes the selected disk(s) only.
Usage Type:	Select the desired usage type. `fsgen` is the file system generic usage type that assumes the volume is being used by a file system. `gen` is the generic usage type that makes no assumptions regarding the data content of the volume. The default is `fsgen`.
Create log subdisk:	Indicate whether a log subdisk is to be created. The default is `No`.
Create file system:	Indicate whether a file system is to be created. When this form is invoked from the Volume Operations menu, the default is not to create a file system (`No`). All fields below this field are only accessible when `Yes` is specified here.
FS type:	Select the desired file system type.
Impose inode limit:	Specify whether to force the file system to have a limit of 65,536 inodes (files). This feature is necessary when making file systems that are compatible with applications for some UNIX systems (such as System V releases prior to System V Release 4). Specifying `No` in this field instructs the file system to create as many inodes as appropriate for the file system's size. The default is `Yes`.
Mount file system:	Specify whether or not you want the file system to be mounted after creation. If the answer is `Yes` (the default), you must specify a mount point in the mount point field. All fields below this field are only accessible when `Yes` is specified here.
Mount point:	Enter the desired mount point for the new file system. If the specified mount point does not already exist, the Visual Administrator will automatically create it. This field is required if the file system is to be mounted.
vxfs mount option:	If `vxfs` is selected as the file system type, various parameters that affect file system performance can be specified when mounting a file system. Select one of the file system configurations provided, each of which represents a certain type of environment. Mount options suitable for the chosen environment will be run. This field is ignored if `vxfs` is not selected as the file system type.
Mount automatically:	Indicate whether this file system should be mounted every time the system comes up (by placing an entry in `/etc/vfstab`). The default is `Yes`.

Striped Volume/FS Create Form

This form creates a striped volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume; the file system fields are greyed out because the default is not to add a file system to the volume.

**Table 47** Striped Volume/FS Create Form
Field	Description
Volume name:	Either use the default or enter a different name for the volume to be created. The name must be unique within this disk group. The maximum length of this field is 31 characters.
Volume size:	Enter the desired volume size. The size should be entered as a number followed immediately by the letter `k`, `m`, `s`, or `g` to indicate kilobytes, megabytes, sectors, or gigabytes, respectively. If no unit is specified, the default is sectors. If the size is not wholly divisible by the stripe unit size, Volume Manager will adjust the volume size up to the next even multiple in order to create the volume. For a striped volume, the volume size should be calculated as follows: vol_size = stripe_width * number_of_columns * n, where n is a number greater than zero. The volume size should be less than or equal to the available free space of the disks. If you click on the Maxsize button, the Volume Manager calculates and displays the maximum volume size possible with this form's current settings. If no disks are selected, the calculation includes available space on all disks in the disk group. Otherwise, the calculation includes the selected disk(s) only.
Usage Type:	Select the desired usage type. `fsgen` is the file system generic usage type that assumes the volume is being used by a file system. `gen` is the generic usage type that makes no assumptions regarding the data content of the volume. The default is `fsgen`.
Create log subdisk:	Indicate whether a log subdisk is to be created. The default is `No`.
Number of Columns:	Enter the number of columns that the volume's plex (mirror) is to have. This is effectively the number of disks on which the volume is to be created. If some number of disks have already been selected, that number of columns appears in this field. This number corresponds to the number of disks across which data will be striped. If no number is specified, Volume Manager selects an appropriate number (usually 2).
Stripe unit size:	Indicate the width of the stripe units on the plex (mirror) that this volume will have. The value specified may be optimized for the particular drive configuration. The default value for this field is 128 sectors, chosen as a good stripe unit size for most systems.
Create file system:	Indicate whether a file system is to be created. When this form is invoked from the Volume Operations menu, the default is not to create a file system (`No`). All fields below this field are only accessible when `Yes` is specified here.
FS type:	Select the desired file system type.
Impose inode limit:	Specify whether to force the file system to have a limit of 65,536 inodes (files). This feature is necessary when making file systems that are compatible with applications for some UNIX systems (such as System V releases prior to System V Release 4). Specifying `No` in this field instructs the file system to create as many inodes as appropriate for the file system's size. The default is `Yes`.
Mount file system:	Specify whether or not you want the file system to be mounted after creation. If the answer is `Yes` (the default), you must specify a mount point in the mount point field. All fields below this field are only accessible when `Yes` is specified here.
Mount point:	Enter the desired mount point for the new file system. If the specified mount point does not already exist, the Visual Administrator will automatically create it. This field is required if the file system is to be mounted.
vxfs mount option:	If `vxfs` is selected as the file system type, various parameters that affect file system performance can be specified when mounting a file system. Select one of the file system configurations provided, each of which represents a certain type of environment. Mount options suitable for the chosen environment will be run. This field is ignored if `vxfs` is not selected as the file system type.
Mount automatically:	Indicate whether this file system should be mounted every time the system comes up (by placing an entry in `/etc/vfstab`). The default is `Yes`.

RAID-5 Volume/FS Create Form

This form creates a RAID-5 volume and optionally creates a file system on the new volume. The form is divided into two sections, one for volume creation and the other for file system creation. Most of the form fields are already set to the defaults for the creation of a new volume; the file system fields are greyed out because the default is not to add a file system to the volume.

**Table 48** RAID-5 Volume/FS Create Form
Field	Description
Volume name:	Either use the default or enter a different name for the volume to be created. The name must be unique within this disk group. The maximum length of this field is 31 characters.
Volume size:	Enter the desired volume size. The size should be entered as a number followed immediately by the letter `k`, `m`, `s`, or `g` to indicate kilobytes, megabytes, sectors, or gigabytes, respectively. If no unit is specified, the default is sectors. If the size specified is not wholly divisible by the stripe unit size, it is rounded up before the volume is created. Since RAID-5 reserves separate space for parity information, the actual space contained in plexes is larger that the addressable size of the volume. The size specified in this field represents the usable space. If you click on the Maxsize button, the Volume Manager calculates and displays the maximum volume size possible with this form's current settings. If no disks are selected, the calculation includes available space on all disks in the disk group. Otherwise, the calculation includes the selected disk(s) only.
Create log subdisk:	Indicate whether a log subdisk is to be created. The default is `Yes`. At least one log subdisk should be created for a RAID-5 volume.
Number of columns:	Enter the number of columns that the volume's plex is to have. Typically, the number needed for RAID-5 should be four columns or more.
Stripe unit size:	Indicate the width of the stripe units on the volume's plex. The value specified may be optimized for your particular drive configuration. Since 32 sectors is considered a good stripe unit size for most systems, it is specified as the default.
Create file system:	Indicate whether a file system is to be created. Since the object of this operation is to create a file system, `Yes` is the selected default.
FS type:	Select the desired file system type.
Impose inode limit:	Specify whether to force the file system to have a limit of 65,536 inodes (files). This feature is necessary when making file systems that are compatible with applications for some UNIX systems (such as System V releases prior to System V Release 4). Specifying `No` in this field instructs the file system to create as many inodes as appropriate for the file system's size. The default is `Yes`.
Mount file system:	Specify whether or not you want the file system to be mounted after creation. If the answer is `Yes` (the default), you must specify a mount point in the mount point field. All fields below this field are only accessible when `Yes` is specified here.
Mount point:	Enter the desired mount point for the new file system. If the specified mount point does not already exist, Visual Administrator will automatically create it.
vxfs mount option:	If `vxfs` is selected as the file system type, various parameters that affect file system performance can be specified when mounting a file system. Select one of the file system configurations provided, each of which represents a certain type of environment. Mount options suitable for the chosen environment will be run. This field is ignored if `vxfs` is not selected as the file system type.
Mount automatically:	Indicate whether this file system should be mounted every time the system comes up (by placing an entry in `/etc/vfstab`). `Yes` is the default.

Volume Resize Form

This form either grows or shrinks a volume using the Volume Manager free space management resources. If new disk space is needed, it will be allocated as necessary; if space becomes unused, it will be added to the free space pool.

**Table 49** Volume Resize Form
Field	Description
Selected Volume:	Displays the name of the volume to be resized. This field is read only and cannot be changed.
Current size:	Displays the current size of the volume to be resized. This field is read only and cannot be changed.
Option:	Select the type of resize operation to be performed. This will determine whether the volume is grown or shrunk to a certain size, or grown or shrunk by a given amount. The default is `Grow` `To`.
Size/Amount:	Enter either the length to which or the amount by which the volume is to be resized. If `Grow` `To` or `Shrink` `To` is selected, this field should reflect the final size. If `Grow` `By` or `Shrink` `By` is selected, this field should reflect the amount by which the size should change. The new volume size should be less than or equal to the available free space of the disks.

Snapshot Form

This form creates a snapshot of the selected volume for backup purposes.

**Table 50** Snapshot Form
Field	Description
Selected Volume:	Displays the name of the volume to be used as the snapshot source. This field is read only and cannot be changed. There must be sufficient free space to accommodate the snapshot volume.
Snapshot name:	Enter the name of the snapshot volume to be created as a backup. Although a default name appears in this field, a name that more closely resembles that of the selected volume should be used for easier association. The maximum length is 14 characters. The snapshot name must be unique.

Volume Create Form

This form creates a volume according to your specifications.

**Table 51** Volume Create Form
Field	Description
Volume name:	Either use the default or enter a different name for the volume to be created. The name must be unique within this disk group. The maximum length of this field is 31 characters. The name specified for the volume must be unique within this disk group.
Usage Type:	Select the desired usage type. `fsgen` is the file system generic usage type that assumes the volume is being used by a file system. `gen` is the generic usage type that makes no assumptions regarding the data content of the volume. The default is `fsgen`. This field is optional.
User:	Enter the name of the user who will be the owner of this volume. This must be a valid user name on the system. The maximum length of this field is 14 characters.
Group:	Enter the name of the group that will own this volume. This must be a valid group name on the system. The maximum length of this field is 14 characters.
Mode:	Set the permissions mode for the new volume. Only numbers of the correct format are valid in this field. The maximum length of this field is 4 characters.
Length:	Enter the length of the volume. If no unit is specified, the default is sectors. Only positive numbers greater than zero are valid. This field is optional.
Plexes:	Displays the number of plexes associated with the volume. If no plexes were selected prior to invoking this form, this field displays 0. This field is read only and cannot be changed.
Read Policy:	Displays the read policy the volume adopts when deciding which plex to write to. These policies are distinguished as follows: Round Robin - All plexes are read equally, in turn. Preferred Plex - A particular plex is specified as the plex to be read whenever possible. The preferred plex will not be read in situations such as when that plex is detached due to I/O failure. Based on plex layouts - All plexes are read equally and in turn, unless a striped plex is present, in which case the striped plex becomes the preferred plex. This option is the default and it typically gives the best read performance. RAID-5 - Indicates a RAID-5 layout.
Preferred Plex:	Lists the name of the preferred plex (mirror) if the Preferred Plex read policy has been specified. The string in this field must be the name of a valid plex that is associated with this volume. This field is required if Preferred Plex is specified in the Read Policy field.
Comment:	Allows you to add an appropriate comment for this volume. The maximum length of the comment is 40 characters. This field is optional.
Startup:	May contain an arbitrary string that is reserved for the user by usage-type utilities. The intention is that this field be used to store options that apply to the volume, such as for the start volumes operation. This is normally a comma-separated list of flag names and option=value pairs. This field is optional.
Logging:	Indicates whether logging is defined and supported on this volume. An undefined log type is included to support old versions of the Volume Manager. The default is `Don't Log`.
Writeback:	Indicates whether the volume is to write back on read failure. If set to `Yes`, an attempt will be made to fix a read error from a participating plex (mirror). The default is `No`.
Putil0:	Lists the permanent utility field 0. This is reserved for Volume Manager use, but may be changed. The maximum length of all Putil fields is 14 characters. This field is optional.
Putil1:	Lists the permanent utility field 1. This field is reserved, but may be changed. This field is optional.
Putil2:	Lists the permanent utility field 2. This field is reserved, but may be changed. This field is optional.

Volume Properties Form

This form provides detailed information on the attributes of a particular volume. Properties of the volume can be changed via this form by altering the current values in the appropriate read/write fields and then clicking on the Apply button.

Click RIGHT mouse button on desired volume icon. (If volume icon is undergoing analysis, press Shift- RIGHT instead.)

Table 52 Volume Properties Form
Field Description
Volume name: The default or enter a different name for the volume. This name must be unique within this disk group. The maximum length of this field is 31 characters. This volume name can be changed by entering another name in this field.
Usage Type: Volume usage type. fsgen is the file system generic usage type that assumes the volume is being used by a file system. gen is the generic usage type that makes no assumptions regarding the data content of the volume. root and swap volumes cannot be created and are presented for informational purposes only. These usage types have restrictions on possible operations. A root volume contains a root file system, while a swap volume is used as the system swap device. This field is read only and cannot be changed.
Utility State: The state that the volume is currently in. This should be either Started, Startable, or Unstartable. This field is read only and cannot be changed.
User: The name of the user who owns this volume. This must be a valid user name. The maximum length of this field is 14 characters.
Group: The name of the group that will own this volume. This must be a valid group name. The maximum length of this field is 14 characters.
Mode: The permissions mode for the volume. Only numbers of the correct format are valid in this field. The maximum length of this field is 4 characters.
Length: The length of the volume. If no unit is specified, the default is sectors. Only positive numbers greater than zero are valid.
Plexes: The number of plexes associated with the volume. If no plexes were selected prior to invoking this form, this field displays 0. This field is read only and cannot be changed.
Read Policy: The read policy the volume adopts when deciding which plex to write to. These policies are distinguished as follows:
Round Robin - All plexes are read equally, in turn.
Preferred Plex - A particular plex is specified as the plex to be read whenever possible. The preferred plex will not be read in situations such as when that plex is detached due to I/O failure.
Based on plex layouts - All plexes are read equally and in turn, unless a striped plex is present, in which case the striped plex becomes the preferred plex. This option is the default and it typically gives the best read performance.
RAID-5 - Indicates a RAID-5 layout.
Preferred Plex: The name of the preferred plex if the Preferred Plex read policy has been specified. The string in this field must be the name of a valid plex that is associated with this volume. This field applies only if Preferred Plex is specified in the Read Policy field.
Comment: A comment relevant to this volume. The maximum length of the comment is 40 characters.
Startup: An arbitrary string that is reserved for the user by usage-type utilities. The intention is that this field be used to store options that apply to the volume, such as for the start volumes operation. This is normally a comma-separated list of flag names and option=value pairs.
Logging: Indicates whether logging is defined and supported on this volume. An undefined log type is included to support old versions of the Volume Manager.
Writeback: Indicates whether the volume is to write back on read failure. If set to Yes, an attempt will be made to fix a read error from a participating plex (mirror).
Putil0: The permanent utility field 0. This is reserved for Volume Manager use, but may be changed. The maximum length of all Putil fields is 14 characters.
Putil1: The permanent utility field 1. This field is reserved, but may be changed.
Putil2: The permanent utility field 2. This field is reserved, but may be changed.
Tutil0: The temporary utility fields 0. This is reserved for Volume Manager use, but can be changed. The maximum length of all Tutil fields is 14 characters.
Tutil1: The temporary utility field 1. This field is reserved, but can be changed.
Tutil2: The temporary utility field 2. This field is reserved, but can be changed.
Kernel State: The accessibility of the volume. This field is read only and cannot be changed.
Number of IO failures: The number of I/O operations that have failed on this volume. This field is read only and cannot be changed.

**Table 52** Volume Properties Form
Field	Description
Volume name:	The default or enter a different name for the volume. This name must be unique within this disk group. The maximum length of this field is 31 characters. This volume name can be changed by entering another name in this field.
Usage Type:	Volume usage type. `fsgen` is the file system generic usage type that assumes the volume is being used by a file system. `gen` is the generic usage type that makes no assumptions regarding the data content of the volume. `root` and `swap` volumes cannot be created and are presented for informational purposes only. These usage types have restrictions on possible operations. A `root` volume contains a root file system, while a `swap` volume is used as the system swap device. This field is read only and cannot be changed.
Utility State:	The state that the volume is currently in. This should be either `Started`, `Startable`, or `Unstartable`. This field is read only and cannot be changed.
User:	The name of the user who owns this volume. This must be a valid user name. The maximum length of this field is 14 characters.
Group:	The name of the group that will own this volume. This must be a valid group name. The maximum length of this field is 14 characters.
Mode:	The permissions mode for the volume. Only numbers of the correct format are valid in this field. The maximum length of this field is 4 characters.
Length:	The length of the volume. If no unit is specified, the default is sectors. Only positive numbers greater than zero are valid.
Plexes:	The number of plexes associated with the volume. If no plexes were selected prior to invoking this form, this field displays 0. This field is read only and cannot be changed.
Read Policy:	The read policy the volume adopts when deciding which plex to write to. These policies are distinguished as follows: Round Robin - All plexes are read equally, in turn. Preferred Plex - A particular plex is specified as the plex to be read whenever possible. The preferred plex will not be read in situations such as when that plex is detached due to I/O failure. Based on plex layouts - All plexes are read equally and in turn, unless a striped plex is present, in which case the striped plex becomes the preferred plex. This option is the default and it typically gives the best read performance. RAID-5 - Indicates a RAID-5 layout.
Preferred Plex:	The name of the preferred plex if the Preferred Plex read policy has been specified. The string in this field must be the name of a valid plex that is associated with this volume. This field applies only if Preferred Plex is specified in the Read Policy field.
Comment:	A comment relevant to this volume. The maximum length of the comment is 40 characters.
Startup:	An arbitrary string that is reserved for the user by usage-type utilities. The intention is that this field be used to store options that apply to the volume, such as for the start volumes operation. This is normally a comma-separated list of flag names and option=value pairs.
Logging:	Indicates whether logging is defined and supported on this volume. An undefined log type is included to support old versions of the Volume Manager.
Writeback:	Indicates whether the volume is to write back on read failure. If set to `Yes`, an attempt will be made to fix a read error from a participating plex (mirror).
Putil0:	The permanent utility field 0. This is reserved for Volume Manager use, but may be changed. The maximum length of all Putil fields is 14 characters.
Putil1:	The permanent utility field 1. This field is reserved, but may be changed.
Putil2:	The permanent utility field 2. This field is reserved, but may be changed.
Tutil0:	The temporary utility fields 0. This is reserved for Volume Manager use, but can be changed. The maximum length of all Tutil fields is 14 characters.
Tutil1:	The temporary utility field 1. This field is reserved, but can be changed.
Tutil2:	The temporary utility field 2. This field is reserved, but can be changed.
Kernel State:	The accessibility of the volume. This field is read only and cannot be changed.
Number of IO failures:	The number of I/O operations that have failed on this volume. This field is read only and cannot be changed.

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