C9300 stack OS upgrade: if doesn't boot, what is fix procedure?

[jmaxwellUSAF]

Hello.

I will soon upgrade the IOS's on a four-stack of Cat-9300 switches. I am following these instructions... Cisco C9300 switch stack IOS-XE upgrade (packetswitch.co.uk) I have left in the flash the old IOS. I expect no issues; however, my boss has asked that I prepare for worst-case scenarios. Thus...

If the IOS's are somehow corrupted so that the IOS does not boot, what is my detailed troubleshoot procedure?

Thank you.

[balaji.bandi]

Most of the upgrades are smooth now

if upgrade fails you should not reboot the stack (if we doing install mode)

we have dont plenty i did not see IOS XE corruption, so make sure you upload correct image and do the MD5 checksum.

and read the release notes target version.

If the switch hardware fails, any way you need to RMA.

[jmaxwellUSAF]

"Verifying an Image Example

In the following example, the /md5 keyword is used to display the MD5 value for the image stored in disk1 of the device. The MD5 value shown in the last line can be compared to the value provided on Cisco.com."

Where at cisco.com is "the value provided at Cisco.com" (the MD5 checksum validation page)?

----

my current switch output:

........................................Done!
verify /md5 (flash:cat9k_iosxe.17.06.04.SPA.bin) = dae85d113b3438d4f00e49ccdd1ec611

[balaji.bandi · Accepted solution]

MD5 if you mouse over on the image you download from software you can see that :

[Flavio Miranda · Accepted solution]

Hi

 If the IOS is corrupted the switch may end up in rommon mode. 

Take a look on this document

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9300-series-switches/216944-troubleshoot-bootloader-rommon-and-pas.html 

It is not possible to elaborate a troubleshooting procedure without a problem in place. But move to rommon is usually the way out for a device when IOS file is not available or corrupted.  

Recovery from rommon is not a really dificult task and I believe this document can help you.

[Leo Laohoo]

In Install Mode, if the firmware is corrupt, the process to extract the packages off the BIN file will abruptly stop.  The switch, however, will not boot and is not in ROMMON.  

In Bundle Mode, if the firmware is corrupt, the switch will go into a boot loop before stopping in ROMMON.

And this is why Install Mode is highly recommended.  Bundle Mode should only be used in extreme cases.  

Please take the time to read the attached document.