How to roll back to old IOS if new IOS crashes? Both IOS on flash.

[news2010a]

Hi, I have been searching this info but I can't find it so I'd appreciate if someone can show me where to find this:

How can I recover "old" IOS in case my new IOS crashes upon power cycling a 2960 switch? Please note that both new IOS and old IOS are still in flash. I already did the 'boot system flash' command pointing to new image OK. So now I just need to power cycle switch so that new IOS can be loaded.

Just need to write a detailed back out plan in case things go wrong.

If you can point me to documentation or kindly tell me steps that would be great.

flash:/

c2960-lanbasek9-mz.122-50.SE1.bin

c2960-lanbase-mz.122-25.SEE3

[Jon Marshall · Accepted solution]

Marlon

Your "boot system flash ..." command can contain both images separated by a semicolon -

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_44_se/command/reference/cli1.html#wp2087341

however this will not necessarily help if you get into a loop ie. the switch loads new IOS then it crashes, reloads and tries new IOS again or if the switch just crashes to ROMMON because typing boot will simply try that IOS again.

So if this happens from ROMMON you need to use the boot command but specify the old IOS -

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_44_se/command/reference/bootldr.html#wp1118871

Jon