Cisco IOS Version help

Hi all can anyone decipher this IOS version for me and give me a clue as to what it will support. Being using it fine until I tried to practice IGRP.
Unfortunately Matt Georges guide doesn't seem to be available at the moment.

C2600-IK903S3-MZ 12.3(21)

Find more posts tagged with

SAVE $250 on Your CISCO Boot Camp — Use Code "EXAM26"

Exclusively for TechExams members for Infosec Boot Camps starting before April 30, 2026

View CISCO Boot Camps

Comments

dtlokee

IGRP has been removed from 12.3, no matter what feature set you run.

you can use the feature navigator on Cisco's website for more information

www.cisco.com/go/fn

billyr

Thanks much appreciated. Been pulling my hair out trying to figure out why I couldnt get it to work.

mikej412

billyr wrote:

Unfortunately Matt Georges guide doesn't seem to be available at the moment.

It's linked in the CCNA FAQ if you have problems finding it....

The "Matt George" guide to Cisco IOS

mgeorge

Sorry about the guide guys. Im doing some extensive updates to it. I guess ill put the old one back on there for the time being.

http://www.freewebs.com/whiteice27/mggios.pdf

enjoy

datchcha

Is igrp being discontinued or something? My routers just came in and i have c2600-j1s3-mz.123-15 and igrp can not be enabled as well.

I did notice the follwoing command

iso-igrp

what does this do?

dtlokee

Yes IGRP is such a lousy protocol it is being removed.

Well really since it does not support VLSM it won't work in most networks today. It converges slowly, and only runs on Cisco equipment. There really are no benefits to running it other than it's has lower CPU and memory overhead than OSPF or EIGRP which isn't really a problem on the routers that can run IOS 12.3. The code space is better utilized for other features.

Here's a document describing the removal of some features in the IOS:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t13/ftjencrg.htm

So much for my XNS network.