[ClusterLabs] How to cancel a fencing request?

[Jehan-Guillaume de Rorthais]

On Tue, 03 Apr 2018 17:35:43 -0500
Ken Gaillot <kgaillot at redhat.com> wrote:

> On Tue, 2018-04-03 at 21:46 +0200, Klaus Wenninger wrote:
> > On 04/03/2018 05:43 PM, Ken Gaillot wrote:  
> > > On Tue, 2018-04-03 at 07:36 +0200, Klaus Wenninger wrote:  
> > > > On 04/02/2018 04:02 PM, Ken Gaillot wrote:  
> > > > > On Mon, 2018-04-02 at 10:54 +0200, Jehan-Guillaume de Rorthais
> > > > > wrote:  
[...]
> > > > 
> > > > -inf constraints like that should effectively prevent
> > > > stonith-actions from being executed on that nodes.  
> > > 
> > > It shouldn't ...
> > > 
> > > Pacemaker respects target-role=Started/Stopped for controlling
> > > execution of fence devices, but location (or even whether the
> > > device is
> > > "running" at all) only affects monitors, not execution.
> > >   
> > > > Though there are a few issues with location constraints
> > > > and stonith-devices.
> > > > 
> > > > When stonithd brings up the devices from the cib it
> > > > runs the parts of pengine that fully evaluate these
> > > > constraints and it would disable the stonith-device
> > > > if the resource is unrunable on that node.  
> > > 
> > > That should be true only for target-role, not everything that
> > > affects
> > > runnability  
> > 
> > cib_device_update bails out via a removal of the device if
> > - role == stopped
> > - node not in allowed_nodes-list of stonith-resource
> > - weight is negative
> > 
> > Wouldn't that include a -inf rule for a node?  
> 
> Well, I'll be ... I thought I understood what was going on there. :-)
> You're right.
> 
> I've frequently seen it recommended to ban fence devices from their
> target when using one device per target. Perhaps it would be better to
> give a lower (but positive) score on the target compared to the other
> node(s), so it can be used when no other nodes are available. you could
> re-manage.  

Wait, you mean a fencing resource can be triggered from its own target? Wat
happen then? Node suicide and all the cluster nodes are shutdown?

Thanks,