tcp(SFF)

tcp -- default information for TCP/IP startup script

Format

# comments
keyword=value

Description

The tcp file (/etc/default/tcp) contains information that the TCP/IP start and stop script tcp(ADMN) reads when TCP/IP is started. Default values in /etc/tcp are overridden by the contents of /etc/default/tcp at system startup or when the tcp startup script is run.

CAUTION: The TCP start and stop script does not verify the accuracy of /etc/default/tcp entries. Displaced or malformed entries will cause TCP/IP to fail or start incorrectly; do not modify the order of the keywords. Whenever possible, use the appropriate graphical administrative interface rather than editing this file directly.

The following keywords can be defined.

System variables

DOMAIN=domain_name: System default domain name.

A value can be assigned to this variable during installation or using the Network Configuration Manager.

NOTE: As of SCO OpenServer Release 5.0.7, the NETMASK and BROADCAST variables are no longer stored in /etc/default/tcp. The Network Configuration Manager now writes netmask and broadcast address values directly into the /etc/tcp file.

Default route variables

GATEWAY=gateway_address: The default route; that is, the IP address of the gateway system to which network traffic is sent if this host does not have an explicit route for that traffic. For more information, see ``Default routes'' in Administering TCP/IP.
DFLTMETRIC="metric value [metric value]": Default route metrics and values as specified in the route(ADMN) manual page. For example:

DFLTMETRIC="-hopcount 1 -mtu 1500"
DFLTMETRIC is optional and can remain empty. It is used only if the GATEWAY variable is set.

Values can be assigned to these variables using the Client Manager or the UNRESOLVED XREF-0 Internet Manager. When values are assigned, the tcp startup script performs the equivalent of:

route add default $GATEWAY $DFLTMETRIC

TCP service daemon variables

STARTDAEMON0-9="daemon_name options"

Starts TCP-related daemons; for example, routing daemons or other TCP services such as SASL, SLP or LDAP. If the command contains spaces or characters special to the shell, it should be quoted. The value of each STARTDAEMONx line is executed verbatim by the shell.

STOPDAEMON0-9="daemon_name options"

Stops the daemons started by the STARTDAEMONx keywords. Daemons are stopped in reverse order from which they are started.

To add the name of the daemon to the list of daemons that /etc/tcp will shut down, prefix the process name with tcp:. For example, if you started a daemon called myrouted with STARTDAEMON0, and it is a simple daemon that does not change its process title or fork other daemons, you could set STOPDAEMON0='tcp:myrouted'. This would add myrouted to the list of processes to grep for and kill during TCP shutdown.

If the string does not start with tcp:, it is executed verbatim by the shell, so any values with spaces or characters For example, if myrouted creates /etc/myrouted.pid, you might want to set:

STOPDAEMON0='[ -f /etc/myrouted.pid ] && kill `cat /etc/myrouted.pid`'

Up to 10 STARTDAEMONx/STOPDAEMONx variable pairs can be set, one variable per line.

Setting router daemon variables

To enable routing, set a STARTDAEMONx/STOPDAEMONx variable pair to the executable file name for a router daemon with options. For example, to use routed with the -g option, set:

STARTDAEMON0="/etc/routed -g"
STOPDAEMON0="/etc/routed"

Valid values are:

/etc/routed options
/etc/gated options
/etc/irdd options

CAUTION: The configuration of multiple router daemons is only appropriate on router systems and should only be attempted by network administrators who are thoroughly familiar with IP routing.

An entry must be added manually to the /etc/default/tcp file before further configuration of the desired router daemon(s). Under most circumstances, if you set a GATEWAY variable, you do not set a routing daemon.

For more information, see ``Configuring Internet Protocol (IP) routing'' in Administering TCP/IP.

DHCP variables

DHCP_CONFIG=interface_name

The network interface to which an IP address will be assigned by a Dynamic Host Configuration Protocol (DHCP) server. For example, to configure the net0 interface to receive an address from a DHCP server, set:

DHCP_CONFIG=net0

If left blank, none of the interfaces are configured for DHCP address allocation. Values can be assigned to this variable using the Network Configuration Manager.

Only one interface can be listed here for DHCP configuration; for information about configuring multiple interfaces, see the dhcpc(ADMN) manual page.

Files

/etc/default/tcp: full pathname of tcp
/etc/tcp: the TCP start and stop script
/etc/rc2.d/: directory containing scripts run by /etc/rc2 when going to multiuser mode
/etc/rc0.d/: directory containing scripts run by /etc/rc0 when shutting down the system