Cisco Catalyst 9200/9300 (Install Mode) Rollbacks During Upgrades

[sixnetcg]

Hi,

I have a question in regards to performing a software-upgrade (in INSTALL mode) for a Cisco Catalyst 9200/9300 series switch in terms of the rollback which is confusing to me.

When you perform a ‘install add file . activate commit’

During the process I notice that it will start removing the package files of the current version (example below):

Example: upgrading from 16.12.03 to 16.12.05

--- Starting list of software package changes ---",
"    Old files list:",
"      Removed cat9k-cc_srdriver.16.12.03a.SPA.pkg",
"      Removed cat9k-espbase.16.12.03a.SPA.pkg",
"      Removed cat9k-guestshell.16.12.03a.SPA.pkg",
"      Removed cat9k-rpbase.16.12.03a.SPA.pkg",
…

Note: I prefer that those packages are not removed so I can do easy rollbacks with the install rollback’ command

However, according to Cisco documentation, if the upgrade doesn’t complete within the default abort-timer window of 2-hours, it will revert back to the previous version.  But those packages were already removed during the ‘install add file activate commit’

So what actually happens?

Thanks!

[Flavio Miranda]

Hi 

 I have no documentation to share so this is just the way I think it works. Those file it deletes is not permanent files, they are generated by uncompressing the .bin file. "..This breaks the .bin file up into smaller .pkg.."

If you repear the process you get the same files.

[sixnetcg]

Thanks for the response.  It's hard to test this out if it's not written in any documentation or to really confirm this.

Furthermore, when you perform a 'install add file X', that command is when those individual .pkg files are created from its original .bin file.

If it needs to revert back to the previous version during an upgrade failure, how does it know which .bin to use?  Because some switches I seen could have multiple .bin files available in its flash.  Adding more to my confusion and trying to see what others have experienced.

[Flavio Miranda]

To be sure how things happen down there, it would be necessary look the script that manage it. Not saying the upgrade process is perfect but I'd say it works just fine most of time. 

[Leo Laohoo]

"activate commit" moves away from the rollback timer.