Upgrade-procedure.md

@@ -17,6 +17,7 @@ This is a documentation for fairkom sysadmins. We have to upgrade nextcloud ever
 1. check admin settings overview page
 1. likely you need to do a `sudo -u faircloud php occ db:add-missing-indices`
 1. check if all apps are working
+1. use the maintenance window for an OS update and reboot if you got a new kernel
 2. remove the Announcement in the Announcement app (so those who did not read it yet won't get it anymore)