We've attempted upgrading some of our H-sphere Web boxes from 3.6.1 to 3.6.3 and in every case we ran into two issues:
1) All PHP/MySQL websites stopped working and we had to manually redo the DB user password in CP to "Long, PHP5.x-only"
2) We had to manually change the "PHP Mode" through the CP for each web site for each client to a valid option as it appears after the update there is no valid PHP parser.
My question is we need to run this update on some heavily utilized WEB boxes which has a lot of clients and websites and need to know how we can avoid the above two issues?
H-sphere upgrade logic is hardcoded and could not be changed.
First of all please be aware that you should perform upgrade cumulatively 3.6.1->3.6.2->3.6.3
Also according to our release notes option with length of hash was included in SPU update of H-sphere 3.6
You can change hash length before the upgrade. Also you can change PHP mode to another one, before the upgrade, which would not cause downtime after upgrade.