Installing and Administering Internet Services

252 Chapter 8
Configuring gated
Configuring the RIP Protocol
• The sourcegateways clause tells gated to send RIP information
directly to the specified routers.
See “RIP Protocol Statement” on page 249 for more information about
these clauses.
Two options for limiting RIP routing information imported by gated are
in the RIP protocol definition in the /etc/gated.conf file:
• The noripin clause in the interface definition tells gated not to
process RIP information received through the listed interfaces.
• The trustedgateways clause tells gated to listen to RIP
information received only from the specified routers.
See “RIP Protocol Statement” on page 249 for more information about
these clauses.
You can also use the gated import and export statements to restrict
and control the route information propagated from one routing protocol
to another. See “Importing and Exporting Routes” on page 292.
Large RIP Configuration Example
Figure 8-2 and the accompanying text describe examples of how gated
might be configured for the RIP protocol in each node within a networked
system.
B, D, and E pass routing information among themselves and update their
routes accordingly. C listens to the RIP conversation among B, D, and E,
and updates its routes accordingly. If routers D and E can both provide a
path to a network, but the path through router D is shorter, nodes B, C,
and E will use router D when routing packets to that network. If D goes
down, E becomes the new router to that network for nodes B, C, and E.