Tuesday, January 15, 2008

Optimize Routing Updates

Dynamic routing protocols such as EIGRP, OSPF & RIP update the routing table through the use of protocol updates. These updates are sent periodically from one router to another and can create quite a bit of traffic on your network.

You can optimize your router and reduce this kind of traffic through the use of the "passive-interface" command. It works by instructing the router not to send update to specific interface(s).

The "passive-interface" command can be used in two ways:

1. Specify an interface that will not participating in routing updates.

Router(config)# router rip
Router(config-router)# passive-interface Ethernet 0/0

2. Make all interfaces passive then use "no passive-interface" on interfaces that you want to participating in routing updates.

Router(config)# router rip
Router(config-router)# passive-interface default
Router(config-router)# no passive-interface Ethernet 0/0

Note that the "passive-interface" command works on all IP routing protocols except BGP.

No comments: