[ClusterLabs] Virtual ip resource restarted on node with down network device

[Ken Gaillot]

On 09/16/2016 10:08 AM, Auer, Jens wrote:
> Hi,
> 
> I have configured an Active/Passive cluster to host a virtual ip
> address. To test failovers, I shutdown the device the virtual ip is
> attached to and expected that it moves to the other node. However, the
> virtual ip is detected as FAILED, but is then restarted on the same
> node. I was able to solve this by using a ping resource which we want to
> do anyway, but I am wondering why the resource is restarted on the node
> and no failure is detected anymore.

If a *node* fails, pacemaker will recover all its resources elsewhere,
if possible.

If a *resource* fails but the node is OK, the response is configurable,
via the "on-fail" operation option and "migration-threshold" resource
option.

By default, on-fail=restart for monitor operations, and
migration-threshold=INFINITY. This means that if a monitor fails,
pacemaker will attempt to restart the resource on the same node.

To get an immediate failover of the resource, set migration-threshold=1
on the resource.

I'm not sure what you mean by "the device the virtual ip is attached
to", but a separate question is why the resource agent reported that
restarting the IP was successful, even though that device was
unavailable. If the monitor failed when the device was made unavailable,
I would expect the restart to fail as well.

> 
> On my setup, this is very easy to reproduce:
> 1. Start cluster with virtual ip
> 2. On the node hosting the virtual ip, bring down the network device
> with ifdown
> => The resource is detected as failed
> => The resource is restarted
> => No failures are dected from now on
> 
> Best wishes,
>   Jens
> 
> --
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