Maintenance mode for updates/changes

[CanadaGuy]

Is there a maintenance mode that will prevent outside requests to do things like updating PHP which takes a long time to compile? Is there a recommended order of operations for making such a change? Same with DB updates or whatever...

 

[MaXi32]

Maybe this should be put in feature request. I also need this one-click maintenance mode to prevent DA users to login and make changes inside DA system during custombuild update or backup and also completely redirect all public sites to a maintenance page during this time.