Urgent: One Cisco VSS chassis booting into Rommon

[Hassan Mwangi]

Hello,

I have configured VSS on my distribution (6509) and my Core (6506). I am now encountering an issue where by one of the chassis boots in rommon mode. This system ahs been stable but this has arised and needs urgent attention.

What is the cause of this and how do i resolve this issue.

Your urgent help will be appreciated.

Kind regards,

Hassan.

[Reza Sharifi]

Hi Hassan.

You probably did not have the boot variable command before the switch rebooted.

In rommon mode type "set" and see if you are pointing to the correct IOS, if not type "boot bootflash IOS name" and see if it boots correctly.

Good Luck

Reza

[Hassan Mwangi]

Hello Reza,

The commands are actually there. When i  force switchover to make the Standby one active, the one that was active goes to rommon.

Below are the commands;

!
boot-start-marker
boot system flash sup-bootdisk:s72033-adventerprisek9_wan-mz.122-33.SXI1.bin
boot system flash slavesup-bootdisk:s72033-adventerprisek9_wan-mz.122-33.SXI1.bin
boot-end-marker
!

[Reza Sharifi]

Hi Hassan,

So every time you force a switch over the active switch boots to rommom?

after the switch over did you remember to save?

Reza

[Hassan Mwangi]

Hello Reza,

Yeah, everytime i force a switch over, the active boots to rommon.

I save the configurations before i force a switchover.

I dont get your question as the active does not come up after the forced switchover.

Any mo info that you need to help me out of this situation??

[Reza Sharifi]

Hassan,

The only thing I can think of is that your IOS is some what old and an upgrade may help. The current one on CCO is SXI3 and seems to be pretty stable.

one more question: when one switch is in rommon, how do you get it to boot? and once booted all the way does VSS function correctly for both switches?

Reza

[Hassan Mwangi]

Hello Reza,

I have the core (6506) and the Distrbution (6509) both are VSS. I first experienced the issue with the distribution which i upgraded to SXI3. I am still monitoring it and have not seen the issue arise again though i didnt know the main reason. The only issue that arised is when you perform a switchover the VSS cannot be accessed using SSH. It can only be accessed using telnet. Can u also help on this one??

The rommon issue came up again, a week down the line with the Core VSS and the clients needed a conclusive explaination why the sytem was behaving in such a manner considering its a critical system for him. Then lead me to consulting in the Netpro Forum. Would this be a bug in the IOS or would you establish the cause if i sent you the relevant configs??

When the switch goes to rommon, i basically console into it and enter the "boot" command which boots the switch. After that, the VSS functions properly for both switches.

[Reza Sharifi · Accepted solution]

Hassan

Regarding the SXI3 with the SSH key corruption your observation is correct but it only happens if you use eFSU to upgrade.  If you simply load the new image and change your boot variable and reboot the SSH does not get corrupted. There is also a bug ID for this and will be resoleved in SXI4.

As for your second question regarding a bug for the rommon issue, I have not seen a bug id but that does not mean there in none.  I would upgrade to a newer code and if the problem still exist open a TAC case and RMA the sup.

HTH

Reza

[Hassan Mwangi]

Hello Reza,

Thanks so much for your support on this issue. You were really of help to me and all others who will read this discussion.

I think that the best way to resolve this issue. I am upgrading the core VSS right now.

For the SSH, i have seen the bug (CSCtc41114). The upgrade or change of Hostname corrupts the RSA keys  and from the work around given in the bug details i have been able to resolve the issue.

Thank you.

Kind regards,

Hassan.