Re: ATM/EIGRP Problems

t.zelenik · ‎06-02-2004

I am using a 2621XM with an AIM-ATM linecard and a VWIC-MFT-T1 card for an ATM to IMA connection. I have configured the T1 controller for ATM and the linecode and framing are correct. The ATM interface is set correctly for the aal5snap encapsulation. The problem I am having is that EIGRP sees the adjacent router and then times out giving an error message on the IMA router saying that the K value is mismatched. I am not sure what that means or where to look. Please help!

ruwhite · ‎06-03-2004

Make certain neither of the two routers have their k values set in the eigrp config. You could post the configs here to verify that...

The second thing is this may not be an actual k value mismatch, but rather EIGRP sending a goodbye message. I thought I had just edited a doc on this, but I can't find it on CCO now.... Essentially, there is a new feature in EIGRP, if a router is shutting down a neighbore relationship for some reason, it will send a "goodbye" message, which is a hello with all the k values set to 255. If the neighbor receiving this hello supports graceful shutdown, it will print out a message about the neighbor going down because of a graceful shutdown. If not, it will print out a k value mismatch message.

Could you check the console log on the other router? Make certain you have log neighbor changes configured on both sides, and see why the other router says the neighbor relationship is failing. If it's sending a goodbye message, the other router should give you more information on why.

:-)

Russ.W

t.zelenik · ‎06-03-2004

Neither router has a K value set out of default.

On the other router, it says that the holdown timer expired. The remote router is running a much newer version of IOS 12.3(6) I believe (I will verify and post later).

Do you think this could be a problem on the ATM settings causing the problem?

I will post more information later, but hopefully this will help.

Tom

t.zelenik · ‎06-03-2004

Log information on the IMA side:

Jun 3 08:27:28.005 CDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 192.168.251.6 (ATM2/ima1.9) is up: new adjacency

Jun 3 08:27:41.509 CDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 192.168.251.6 (ATM2/ima1.9) is down: K-value mismatch

Jun 3 08:27:45.837 CDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 192.168.251.6 (ATM2/ima1.9) is up: new adjacency

Jun 3 08:27:59.697 CDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 192.168.251.6 (ATM2/ima1.9) is down: K-value mismatch

Jun 3 08:28:04.301 CDT: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 192.168.251.6 (ATM2/ima1.9) is up: new adjacency

EIGRP settings on the IMA side:

router eigrp 2416

redistribute eigrp 100

network 10.16.1.0 0.0.0.255

network 10.230.17.0 0.0.0.255

distribute-list 1 in

no auto-summary

no eigrp log-neighbor-changes

!

router eigrp 100

redistribute eigrp 2416

network 10.0.0.0

network 192.168.251.0

distribute-list 1 in

no auto-summary

access-list 1 permit 172.30.0.0 0.0.255.255

access-list 1 permit 192.168.251.0 0.0.0.255

access-list 1 deny 10.10.0.0 0.0.255.255

access-list 1 deny 10.2.0.0 0.0.255.255

access-list 1 deny 10.3.0.0 0.0.255.255

access-list 1 deny 192.168.0.0 0.0.255.255

access-list 1 remark Above denies conflict networks

access-list 1 permit 10.0.0.0 0.255.255.255

Show Version:

Cisco Internetwork Operating System Software

IOS (tm) 7200 Software (C7200-JS-M), Version 12.2(15)T11, RELEASE SOFTWARE (fc2)

TAC Support: http://www.cisco.com/tac

Compiled Sat 31-Jan-04 11:07 by nmasa

Image text-base: 0x60008954, data-base: 0x61F8E000

ROM: System Bootstrap, Version 12.0(19990210:195103) [12.0XE 105], DEVELOPMENT SOFTWARE

BOOTLDR: 7200 Software (C7200-BOOT-M), Version 12.0(2)XE2, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)

Local_Oklahoma uptime is 7 weeks, 17 hours, 45 minutes

System returned to ROM by reload at 07:46:27 CDT Wed Apr 14 2004

System restarted at 14:47:47 CDT Wed Apr 14 2004

System image file is "slot0:c7200-js-mz.122-15.T11.bin"

cisco 7206VXR (NPE300) processor (revision B) with 122880K/40960K bytes of memory.

Processor board ID 16066266

R7000 CPU at 262Mhz, Implementation 39, Rev 1.0, 256KB L2, 2048KB L3 Cache

6 slot VXR midplane, Version 2.0

Last reset from power-on

Bridging software.

X.25 software, Version 3.0.0.

TN3270 Emulation software.

Primary Rate ISDN software, Version 1.1.

1 FastEthernet/IEEE 802.3 interface(s)

10 ATM network interface(s)

12 Channelized T1/PRI port(s)

125K bytes of non-volatile configuration memory.

20480K bytes of Flash PCMCIA card at slot 0 (Sector size 128K).

46976K bytes of ATA PCMCIA card at slot 1 (Sector size 512 bytes).

4096K bytes of Flash internal SIMM (Sector size 256K).

Configuration register is 0x102

ruwhite · ‎06-03-2004

This makes sense--one end is dropping the neighbor relationship because of the hold timer expiring, and when it does, it sends a "goodbye" message, which the other router interprets as a mismatched k value problem, dropping the neighbor relationship on that end. It's working as the feature was designed. :-)

I would chase the hold timer expirations at this point--why are we dropping enough eigrp traffic to lose the relationship. I would first look at the interface counters to see what they are saying (do you have a lot of drops?). Does the neighbor relationship ever come up at all?

:-)

Russ.W

t.zelenik · ‎06-03-2004

It ended up being an ATM configuration problem (although I am skeptical). I didn't have the vbr-nrt statement corrct, which was causing drops. I think that I was looking a layer too high!

Thanks for all the help!

Tom