System Administration Guide: IP Services

How to Specify a Router for the Network Client

  1. If only one router is on the network and the network configuration server is to specify its name automatically, ensure that no /etc/defaultrouter file exists on the network client.

  2. To override the name of the default router that is provided by the network configuration server, do the following:

    1. Create /etc/defaultrouter on the network client.

    2. Type the host name and IP address of the machine you have designated as the default router.

    3. Add the host name and IP address of the designated default router to the network client's /etc/inet/hosts.

  3. If you have multiple routers on the network, create /etc/defaultrouter on the network client, but leave this file empty.

Creating /etc/defaultrouter and leaving this file empty causes one of the two dynamic routing protocols to run: ICMP Router Discovery Protocol (RDISC), or Routing Information Protocol (RIP). The system first runs the program in.rdisc, which looks for routers that are running the router discovery protocol. If in.rdisc finds one such router, in.rdisc continues to run and monitors the routers that are running the RDISC protocol.

If the system discovers that routers are not responding to the RDISC protocol, the system uses RIP and runs the in.routed daemon to monitor the routers.