You'll need an agent that complies with the FenceAgentAPI. All pacemaker cares about, fundamentally, is the agent's exit code (save for the meta-data call it uses to know what is a valid config). It's entirely up to you when you decide that a fence action has succeeded or failed.
Of course, reporting success without actually fencing the target could end disastrously, so do your due diligence. https://github.com/ClusterLabs/fence-agents/blob/master/doc/FenceAgentAPI.md digimer On 2020-08-04 4:57 p.m., Philippe M Stedman wrote: > Hi Andrei, > > What if we had no hardware device and all we wanted to do was run a > single command when fencing off a failed node. Would that be possible? > > Are fencing operations dependent on underlying hardware for Pacemaker? > > Thanks, > > *Phil Stedman* > Db2 High Availability Development and Support > Email: pmste...@us.ibm.com > > Inactive hide details for Andrei Borzenkov ---07/30/2020 11:02:58 > PM---30.07.2020 22:17, Philippe M Stedman пишет: >Andrei Borzenkov > ---07/30/2020 11:02:58 PM---30.07.2020 22:17, Philippe M Stedman пишет: > > > From: Andrei Borzenkov <arvidj...@gmail.com> > To: developers@clusterlabs.org, Philippe M Stedman > <pmste...@us.ibm.com>, nw...@redhat.com > Cc: Toby Haynes <thay...@ca.ibm.com>, Gerry R Sommerville > <ge...@ca.ibm.com>, Alan Y Lee <yka...@ca.ibm.com> > Date: 07/30/2020 11:02 PM > Subject: [EXTERNAL] Re: [ClusterLabs Developers] How to implement > fencing agent with no associated hardware device with Pacemaker? > > ------------------------------------------------------------------------ > > > > 30.07.2020 22:17, Philippe M Stedman пишет: >> >> Thanks Gerry. >> >> Hi Reid, >> >> The shared storage solution we are using has clustering capabilities > of its >> own built into it and is able to remotely fence off the lost node, all we >> need to do is run the command to expel/fence the lost node as part of our >> own custom fencing agent on the surviving node. >> >> FYI, the shared storage solution I am referring to here is IBM Spectrum >> Scale. >> > > ... > >> >> On Wed, Jul 29, 2020 at 8:34 PM Philippe M Stedman <pmste...@us.ibm.com> >> wrote: >> Hi ClusterLabs developers, >> >> I am looking into how to develop a fencing agent for Pacemaker that is >> not associated to any underlying hardware device. In our case we have >> two servers (we will expand to more in the future) which have > access to >> shared storage. When one of the two nodes fails, we expect the >> surviving node to invoke our user-defined fencing agent and run a >> series of commands which will "expel" the lost host from accessing >> shared storage. >> >> Do you have any advice on how to go about implementing such a > solution? >> All the examples I can find online revolve around using some sort of >> underlying hardware device to implement fencing. >> > > In this case your fencing *is* associated with specific underlying > hardware device. Just start with any of existing fencing or stonith > agents and fill in commands to your underlying hardware to fence off > node. You probably will need some sort of mapping from node name to > whatever is required by your hardware to identify it. > > > > > > _______________________________________________ > Manage your subscription: > https://lists.clusterlabs.org/mailman/listinfo/developers > > ClusterLabs home: https://www.clusterlabs.org/ > -- Digimer Papers and Projects: https://alteeve.com/w/ "I am, somehow, less interested in the weight and convolutions of Einstein’s brain than in the near certainty that people of equal talent have lived and died in cotton fields and sweatshops." - Stephen Jay Gould _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/developers ClusterLabs home: https://www.clusterlabs.org/