Magento Upgrade resulted in site going down:

  • We had a major issue today
  • Without informing us client did proceed with Magento upgrade through some clicks in Admin
  • Site was on 4.0.1 and was upgraded to 4.1.1 but the upgrade didn’t do complete upgrade.Some files were upgraded others couldn’t be as some permissions setting might have stopped it from proceeding
  • This resulted in Admin sales Module for order part go down

Note :Upgrade Magento needs more thoughts then just a click on upgrade.

Also see following :