3750 Cluster Switches Rebooting

[burden010]

Hi,

We have a cluster of 3 3750's and two in the cluster keep restarting without warning. When performing a 'Show Ver' on the cluster I get this error:

System returned to ROM by error - Debug Exception (Could be NULL pointer dereference) Exception (0x2000)!, PC 0x16E0DC

Does anyone know what this means?

Thanks,
Paul

 

[North323]

the memory could be going...

 

[jeter]

It is odd that it's only the two switches. Are you debugging on these switch? U All to turn it off...

Are the other switches just like the ones rebooting.
IOS Ver, memory, etc etc.


Go Army!
Tek-TIP Member 19,650

 

[burden010]

Hi guys,

Yep all three are the same build and software revision.

OK to the memory might be going but that's not really a fix I can implement just to see if it works as I am 300 miles from the site.

I tried looking up the error message on the Cisco knowledge base but I do not have the proper access to the site for that apparently. Would someone be able to check this out for me please?

Thanks for your help,
Paul

 

[jeter]

What ver of IOS are you running?


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Tek-TIP Member 19,650

 

[burden010]

Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
1 28 WS-C3750G-24PS 12.2(25)SEB4 C3750-IPBASE-M
2 28 WS-C3750G-24PS 12.2(25)SEB4 C3750-IPBASE-M
* 3 28 WS-C3750G-24PS 12.2(25)SEB4 C3750-IPBASE-M

 

[burtsbees]

I'd check the stacking cable. They are notorious for going bad, especially at the connectors.

/

tim@tim-laptop ~ $ sudo apt-get install windows
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Couldn't find package windows...Thank Goodness!

 

[burden010]

Thanks burtsbees. I will definitely check that out. The problem I have though is that before going to site, I need to have a definite fix in mind. If that or memory wasn't the issue, I would have wasted a full working day and travel expenses. I know I.T. is about troubleshooting but unless I can guarantee that I have even a good shot at fixing this on the day, I will not get sign off.

I know it might be a lot to ask but could someone with a Cisco account check out the error on the website?

Thanks a lot in advance.

 

[jeter]

From Cisco

Cisco bug ID CSCsa72400

Debug Exception (Could be NULL pointer dereference) Exception (0x2000)!

As a workaround, do not connect 802.3af non-standard class PDs, or even bad or loopback cables, to the switch because the switch can detect the class incorrectly.

In order to resolve this issue, upgrade to Cisco IOS Software Release 12.2(25)SEA on the switch. Alternatively, upgrade to the latest maintenance release, which can be downloaded from Cisco Downloads.

Refer to the Debug Exception (Could be NULL pointer dereference) section of Catalyst 3750 Series Switches Troubleshoot Common Issues for more information.


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[nlk358]

I have similar issue just don't have the Null error message on sh ver:

System returned to ROM by power-on

was it the memory, cables or IOS upgrade?

It was only one switch but today have 2 different swithces restarting and the first switch stayed up.

 

[vipergg]

Check cables and upgrade the stack , doubt you have memeory going bad in 2 switches. Think the latest is like 12.2.52SG or soemthing like that.

 

[VinceWhirlwind]

I will echo Burtsbees.
Plus, call it a "stack", not a cluster.
Check you have correctly cabled all 3 stacking cables.
Take some spare stacking cables with you when you go on-site and replace them.