IGRP and EIGRP

[paulpagecisco]

I have just installed a 2801 with a WIC serial WAN module and a 9 port fa module. The other router (2500) connected by PPP at remote location is using IGRP instead of EIGRP as is on the new 2801. Does anyone know if this is going to cause a problem with the communication between the two sites?

[Jon Marshall]

Paul

If you use the same AS number for both EIGRP and IGRP then there will be automatic redistribution between the 2 routing protocols.

You would need to have an IGRP process running on your 2801 which would peer with the 2500 at the remote site.

Jon

[Richard Burts]

Jon

I just checked with the Feature Navigator and I can not find any IOS image for the 2801 that supports IGRP. (Cisco stopped supporting IGRP in recent versions of code.) I believe that the solution to this needs to be to get the 2500 to run EIGRP instead of IGRP. EIGRP was supported on the 2500 routers in lots of versions of IOS and it is likely that the 2500 will have support for EIGRP.

If there is any issue with EIGRP on the 2500 then perhaps the solution would be to run RIP or OSPF on both routers. For them to communicate they must find some protocol that they both run.

HTH

Rick

[Jon Marshall]

Rick

It never occured to me that IGRP could not be run on the latest versions of code. I wasn't aware that Cisco has ceased support for it in the latest versions either. As you can tell i don't use IGRP in any of the networks i have come across :-)

Thanks for letting me know, rated

Jon

[Richard Burts]

Jon

It has been a long time since I have used IGRP. I do not remember precisely when IGRP was dropped, but I remember reading an announcement (perhaps in release notes) that it was deprecated and would no longer be supported. Thanks for the rating.

HTH

Rick

[paulpagecisco]

I suppose I will need to run eigrp on the old 2500, it seems by enabling router eigrp 20 with the two ip's didnt fix the no WAN problem. I wonder if I can telnet into them, man I hope the IOS is capable of EIGRP on the older 2500. Thanks all.

[Richard Burts]

Paul

EIGRP has been supported on 2500 for a very long time. I believe that your 2500 will be capable of running EIGRP.

This post mentions eigrp 20. Other threads that you have started show igrp using igrp 2. If you use eigrp 2 then both processes will communicate with each other. But if you run igrp 2 and eigrp 20 then they will not communicate and you will need to do redistribution between the processes. I suggest that you try eigrp 2.

HTH

Rick