Re: [ovirt-users] Engine Backup/Restore Question
On Fri, Sep 15, 2017 at 3:04 PM, Alan Griffiths <apgriffiths79(a)gmail.com> wrote:
Hi,
Currently testing my recovery plan for HE failure.
I run a hosted engine, but in the event of some failure of the engine VM i
want to be able to quickly restore the engine to a standalone host running
independent of Ovirt (in this case a VM running on ESXi).
On a dry run I restore the backup onto the ESXi VM and run engine-setup. At
this point it fails with an error that I am not in Global Maintenance mode.
How do you backup, and how do you restore?
If I put the cluster into maintenance mode before performing the backup then
it works correctly. So is it necessary to do this on every backup? I can
find nothing in the documentation detailing this as a requirement?
You might want to look at this:
https://bugzilla.redhat.com/show_bug.cgi?id=1403903
and the linked patches.
Alternatively it seems I can manually update the ha_global_maintenance
column in the vds_statistics table before running engine-setup, but not sure
of the implications of doing this.
The way this works with engine-backup is:
We added a new option DbJustRestored, which defaults to False.
engine-backup --mode=restore sets it to True.
engine-setup checks if it's False, and if so, goes on to check
ha_global_maintenance.
So in principle, it should be enough to:
UPDATE vdc_options SET option_value='1' WHERE
option_name='DbJustRestored';
However, this isn't exposed to engine-config, and is not considered an
"external/official API".
ovirt-4.0.6.3
Above is for 4.1. You might want to upgrade.
Or just reset ha_global_maintenance, but I am not aware of anyone
verifying this or analyzing the implications.
Best,
--
Didi