[ovirt-users] Change network of ovirt-nodes of a self-hosted engine cluster

[Yedidyah Bar David]

----- Original Message -----
> From: "Sandro Bonazzola" <sbonazzo at redhat.com>
> To: "Kostyrev Aleksandr" <kostyrev at tutu.ru>, "Users" <users at ovirt.org>, "Martin Sivak" <msivak at redhat.com>, "Yedidyah
> Bar David" <didi at redhat.com>, "Fabian Deutsch" <fabiand at redhat.com>
> Sent: Monday, March 30, 2015 9:44:05 AM
> Subject: Re: [ovirt-users] Change network of ovirt-nodes of a self-hosted engine cluster
> 
> Il 30/03/2015 08:40, Sandro Bonazzola ha scritto:
> > Il 25/03/2015 14:32, Kostyrev Aleksandr ha scritto:
> >> Good day!
> >>
> >> I'm in position when I have to change network settings of three
> >> ovirt-nodes that comprise my cluster with hosted engine.
> >> Am I correct that to change network is not a big deal and it is possible?
> >> My plan was:
> >> 1. shutdown all vms (except engine itself) on all nodes.
> >> 2. enable maintenance mode on all nodes, except the one with running
> >> engine
> > 
> > I think you should use Hosted Engine global maintenance while doing this.
> > If for some reason the gateway configured in hosted_engine.conf become
> > unreachable I'm not sure it won't try to migrate the VM.
> > Adding Martin to the loop.
> > 
> 
> Also if for some reason the storage become unavailable during the network
> settings update, the engine VM will be paused due to missing storage.
> I'm not sure about what will happen with the SSL certificates, didi?

In 3.5+, the certs all use the hostnames, which I understand are not intended
to be changed, so no issue there.

If some of the hosts were deployed with <= 3.4 and upgraded, the certs will
use the IP address, and this will not change unless you manually reinstall
(re-deploy?). Didn't try that. I guess at least some things will fail.

> 
> >> 3. change network settings in engine node
> >> 4. shut engine down with hosted-engine --vm-stop
> >> 5. change network settings on all nodes, verify that nodes can ping each
> >> other
> >> 6. start engine with hosted-engine --vm-start
> >> 7. change VLAN tag at Logical Network for VMs
> >> 8. activate nodes
> >> 9. start vms
> >>
> >> Does it make sense?
> 
> If you manage to end successfully the migration it would be really nice to
> have a wiki page describing the steps you took for this task.

Indeed!

Best,
-- 
Didi