Thanks for the question, @kumar !

This doc lays out the entire process:

https://documentation.commvault.com/11.25/expert/2171_commcell_environment_upgrades.html

In short, download the Maintenance Release, then upgrade the Commserve first, then Media Agents, then clients.

It shouldn’t take too long, though I can’t really give you any estimate since it’s so contextual to your environment.

Maybe 5-20 minutes per server?  Or Less?

You’re also jumping up a few releases, so I could be off by a lot.

what about license server firstly we need to upgrade that server ?

Kumar is your license server on a standalone server with your metrics server ? if so you  can update that 1st and then do the CS.

@kumar as pointed by Gary, update your license server first, then the child CS and so on.

License server should not be on a lower version than the child CS.

https://documentation.commvault.com/11.25/expert/6998_setting_up_licensing_server_for_multi_commcell_environment.html

So we need to made changes on MYSQL side as well…As MYSQL is store all the information into the DB.

Also what about DR server we are using DR as well in our environment.