LDoms and Maintenance Mode
By Owen Allen-Oracle on Aug 01, 2013
I got a few questions about how maintenance mode works with LDoms.
"I have a Control Domain that I need to do maintenance on. What does being put in maintenance mode actually do for a Control Domain?"
Maintenance mode is what you use when you're going to be shutting a system down, or otherwise tinkering with it, and you don't want Ops Center to generate incidents and notification of incidents. Maintenance mode stops new incidents from being generated, but it doesn't stop polling, or monitoring, the system and it doesn't prevent alerts.
"What does maintenance mode do with the guests on a Control Domain?"
If you have auto recovery set and the Control Domain is a member of a server pool of eligible systems, putting the Control Domain in maintenance mode automatically migrates guests to an available Control Domain. When a Control Domain is in maintenance mode, it is not eligible to receive guests and the placement policies for guest creation and for automatic recovery won't select this server as a possible destination. If there isn't a server pool or there aren't any eligible systems in the pool, the guests are shut down.
You can select a logical domain from the Assets section to view the Dashboard for the virtual machine
and the Automatic Recovery status, either Enabled or Disabled.
To change the status, click the action in the Actions pane.
"If I have to do maintenance on a system and I do not want to initiate auto-recovery, what do I have to do so that I can manually bring down the Control Domain (and all its Guest domains)?"Use the Disable Automatic Recovery action.
"If I put a Control Domain into maintenance mode, does that also put the OS into maintenance mode?"
No, just the Control Domain server. You have to put the OS into maintenance mode separately.
"Also, is there an easy way to see what assets are in maintenance mode? Can we put assets into, or take them out of, maintenance mode on some sort of group level?"
You can create a user-defined group that will automatically include assets in maintenance mode. The docs here explain how to set up these groups. You'll use a group rule that looks like this: