move from static routing to eigrp

[jamesallan]

My company is looking to move from a strictly static ip routing config to EIGRP. We are using 4000 and 4500 series L3 switches running Cisco IOS

instead of CAT IOS. I understand how to enable EIGRP but am not sure of how the static routes will be affected when EIGRP is enabled. We do not want to redistribute EIGRP out to the WAN and just want to keep EIGRP internally on our LAN.

[cdusio]

Static routes by default have a metric of 1 when pointed to an ip address and 0 when pointed to an interface I.E. Serial 0/0

Enabling EIGRP on the LAN is potentially unnecessary depending on your environment as if you have a LAN switching environment and your networks are all on the same switches with the exception of the WAN circuits, then you gain nothing.

That being said, you would want to enable EIGRP if you have redundant paths to remote networks for example.

EIGRP metric is 90 so it would not be preferred over static routes unless you have modified the default metrics.

HTH

Chris

[mheusinger]

Hello,

just a small clarification of the previous post: it should read "administrative distance" (AD) and not "metric". To summarize the statements, the static routes will be prefered because they have a smaller AD than EIGRP. The router decides with AD, which of two routing processes (static, eigrp) announcing the same network it should believe more. smaller values are more "trustworthy".

Generally you can control, where EIGRP is activated through network statements:

interface ethernet0

description LAN

ip address 192.168.1.1 255.255.255.0

interface serial0

description WAN

ip address 10.1.1.1 255.255.255.252

router EIGRP 10

network 192.168.1.1 255.255.255.255

redistribute connected

redistribute static

no auto-summary

This will prevent EIGRP to be activyted accross the WAN link, but still announce the network.

The "redistribute static" will announce all static routes found in the IP routing table, which will allow connectivity in your environment.

Hope this helps! Please rate all posts.

Regards, Martin