Red Hat Bugzilla – Bug 1213289
[Docs] [Admin] [RFE] More information on placing hosts in maintenance mode is required
Last modified: 2016-02-10 13:57:00 EST
More information on placing hosts into maintenance mode and activating hosts that are in maintenance mode is required. Placing hosts in maintenance mode - * What configuration requires a host to be placed in maintenance mode? * Should a host be placed into maintenance mode before a reboot? * What effect does placing a host into maintenance mode have? - Does VDSM stop? - Are connections to storage stopped? - What happens to the SPM role? Activating hosts - * When is it safe to reactivate a host? - After confirming reboot? - Will activating a host when the host is not ready break anything? - Do VMs previously on the host return to that host? - What happens to the SPM role?
Notes - * The 'Virtual Machines' column of the 'Hosts' tab shows how many virtual machines are being migrated. Ideally all, but only those being actively migrated at a given time. * If migration doesn't work, you can click 'Activate' on the host to stop the operation placing it into maintenance mode. You can then click 'Cancel Migration' on the VM to stop migration. This information must be included to provide troubleshooting and rollback information.
Assigning to Andrew for review.
Can you please help answer the questions in description?
(In reply to Andrew Dahms from comment #0) > More information on placing hosts into maintenance mode and activating hosts > that are in maintenance mode is required. > > Placing hosts in maintenance mode - > > * What configuration requires a host to be placed in maintenance mode? Basically anything that might cause vdsm to stop working properly, if you know of network/storage issues or you plan a maintenance work that might cause network/storage issues, and etc. The guideline should be the same as if you have a bare-metal host running some applications. > * Should a host be placed into maintenance mode before a reboot? Yes. > * What effect does placing a host into maintenance mode have? > - Does VDSM stop? No. > - Are connections to storage stopped? I think they are. Allon? > - What happens to the SPM role? > If that's the SPM, it will move to another host. > Activating hosts - > > * When is it safe to reactivate a host? > - After confirming reboot? What do you mean by that? The "confirm host has been rebooted" button? You won't need it if you put the host into maintenance. > - Will activating a host when the host is not ready break anything? Shouldn't break anything, but it might fail. > - Do VMs previously on the host return to that host? No. > - What happens to the SPM role? If you already have another SPM then nothing.
Yaniv - what does this needinfo refer to? Where's the question?
See the question to you in comment #4.
(In reply to Oved Ourfali from comment #4) > > - Are connections to storage stopped? > > I think they are. Allon? They SHOULD be. In practice, we have several bugs around that area. I wouldn't emphasize it.
Re-assigning to Tahlia for review given current scheduling.
Updated 3.6 documentation now available at https://access.redhat.com/documentation/en/red-hat-enterprise-virtualization/