do not start HA VMs on some nodes eg. those running ceph

[liska_]

Hi,
I want to achieve running HA VM just on selected nodes and not on ceph nodes, or just have these nodes as a "disaster" backup.
I found on this page http://pve.proxmox.com/wiki/Ceph_Server following sentence:
If you do not want to run virtual machines and Ceph on the same host, you can just add more Proxmox VE nodes and use these for running the guests and the others just for the storage.

How can I differ those nodes? Or at least how can I select a default node where vm should be running? Is it possible somehow? I think I have red about it somewhere. I was searching a lot but have not found any answer so far.

 

[e100]

What you want is failover domains.

You will need to manually edit the cluster.conf file to create them.

cp /etc/pve/cluster.conf /etc/pve/cluster.conf.new

Edit the /etc/pve/cluster.conf.new file
Increment config_version= at the top.

Create failover domains something like this:

</clusternodes>
  <rm>
    <failoverdomains>
      <failoverdomain name="A-B" restricted="1" ordered="1" nofailback="1">
        <failoverdomainnode name="A" priority="1"/>
        <failoverdomainnode name="B" priority="100"/>
      </failoverdomain>
      <failoverdomain name="B-A" restricted="1" ordered="1" nofailback="1">
        <failoverdomainnode name="B" priority="1"/>
        <failoverdomainnode name="A" priority="100"/>
      </failoverdomain>
  </failoverdomains>

In GUI Apply the new configuration and then add VMs to the particular failover domain you want it in.

 

[liska_]

Thanks a lot for your answer!
So in my case if I want to have a ceph nodes just for worst case scenario, I would set just one failover domain like this?
<code>
<failoverdomain name="A-B" restricted="1" ordered="1" nofailback="1">
<failoverdomainnode name="A" priority="1"/>
<failoverdomainnode name="B" priority="1"/>
<failoverdomainnode name="ceph_A" priority="100"/>
<failoverdomainnode name="ceph_B" priority="100"/>
</failoverdomain>
</code>
Is a actual load on nodes taken in account when starting vm or just something?