On Wed, 2008-05-21 at 11:13 +0800, Xinwei Hu wrote: > We had a deployment of this kind running for more then a half year. > 2 lessons we had so far: > > 1. Start a "standalone" heartbeat inside VM is the best option so far. > i.e "ucast lo 127.0.0.1" in ha.cf > It's the simplest way to have monitoring and restarting inside VM.
Yes. we thought of that but want to use it as the last resort. > 2. Manage VMs as Xen resources in a cluster of all dom0. > However, > a. VMs might be migrated between dom0s anytime, so set dom0 as a > parameter to STONITH plugin is not ideal in practice. (The same > problem applies to VMware ESX server also.) > b. VM is a typical example that we'd better support "inheritance" > for RA. VM's RA can only tell whether it's running, but there're > different ways to tell if the OS (Linux, BSD, Windows, Netware) inside > is health. If this "inheritance" implementation can bring proportionate value then let us implement it. Lon Hohberger has already shown interest in this. May I request to Andrew Beekhof and other veterans :) to advise on implementation complexity versus use of this feature. Thanks for sharing your valuable experience. > > My .2c > > 2008/5/19 Andrew Beekhof <[EMAIL PROTECTED]>: > > > > On May 19, 2008, at 7:14 AM, Nitin wrote: > > > >> On Fri, 2008-05-16 at 15:08 +0200, Andrew Beekhof wrote: > >>> > >>> On May 16, 2008, at 3:04 PM, Nitin wrote: > >>> > >>>> Hello, > >>>> > >>>> I would like to make my virtual machines (DomUs) resources to > >>>> participate in the HA cluster. Dom0 (Physical Host) may or may not > >>>> have > >>>> resources. > >>>> > >>>> To do this I would like to treat DomUs as *resource* in the cluster as > >>>> opposed to treating them as *nodes*. I am planning to write OCF > >>>> resource > >>>> agents for virtual machines. But I am not very sure about how to > >>>> make a > >>>> resource's resource to participate in the cluster. > >>>> > >>>> Is there any configuration in existing structure to achieve this?? > >>>> If no > >>>> then please tell me how to go about creating a "container" resource in > >>>> CRM. > >>> > >>> Why not just use the Xen agent if you don't want them to be cluster > >>> nodes? > >>> Or do you mean that you want them to both be resources and to run > >>> other resources too? > >> > >> Yes. Please advise me how to go about it. > >> Thanks a lot for reply. > > > > We don't have a clean way to do that yet > > > > Possible options: > > a) start the services at VM boot (you don't get monitoring) > > b) start the services at VM boot and modify the Xen agent to monitor the > > services inside the VM (ugly) > > c) add a proxy resource to start/stop/monitor the services inside the VM > > (complex) > > d) implement a generic version of c) > > e) have the VM join the cluster (makes stonith and quorum "interesting") > > f) wait for us to implement clusters-of-clusters which also solves this > > scenario "for free" > > g) something else i've not thought of > > > > _______________________________________________ > Pacemaker mailing list > Pacemaker@clusterlabs.org > http://list.clusterlabs.org/mailman/listinfo/pacemaker _______________________________________________ Pacemaker mailing list Pacemaker@clusterlabs.org http://list.clusterlabs.org/mailman/listinfo/pacemaker
