On Wed, 2022-06-08 at 20:28 +0530, Sridhar K wrote: > Thanks a lot, Ken,Andrie for the time and guidance it was really > helpful. > > will proceed with the below approach > > [A preferred setup would be to run corosync and pacemaker on the VMs, > and configure bundles for the db containers.] > > I will try to get comfortable with bundle approach , referring > https://wiki.clusterlabs.org/wiki/Bundle_Walk-Through > > In above link, it's said at the start [Configure a test cluster of at > least two cluster nodes with Pacemaker 1.1.17 or later] > but in the section > Configure the cluster > Our example needs the run-command option only because we are running > Pacemaker 1.1 inside the container: > > In short, we have a pacemaker cluster with 2 nodes(i,e full stack > pacemaker installed) and a bundle that has a docker/podman image the > image has only pacemaker-remote installed in it. > i,e Line > RUN yum install -y httpd bind-utils curl lsof wget which pacemaker > pacemaker-remote resource-agents > Is my understanding correct, or in the image built we have a full- > stack pacemaker as well.
You at least need the pacemaker-cli package as well. The container will only run pacemaker-remoted, but it's worthwhile to install the full pacemaker package because it has ancillary files that are useful. (In the just-released 2.1.3 version, the crm_attribute tool is now in the pacemaker-cli package, so that is not as big a deal anymore.) > > In case of any other links w.r.t usage of bundle/examples, Please > share the same. The walk-through is a good start. For fuller details, see: https://clusterlabs.org/pacemaker/doc/2.1/Pacemaker_Explained/singlehtml/index.html#bundles-containerized-resources > > Regards > Sridhar > > > On Wed, 8 Jun 2022 at 19:46, Andrei Borzenkov <arvidj...@gmail.com> > wrote: > > On 08.06.2022 17:01, Ken Gaillot wrote: > > > On Wed, 2022-06-08 at 18:31 +0530, Sridhar K wrote: > > >> Hi Team, > > >> > > >> Required guidance w.r.t below problem statement > > >> > > >> Need to have a HA setup for SQLServer running as a docker > > container > > >> and HA managed by the Pacemaker which is running as a separate > > docker > > >> container. > > >> > > >> I have done a setup where pacemaker and SQL Server are running > > as a > > >> single docker container, able to achieve HA. > > >> > > >> How to achieve the same when Pacemaker , and Sqlserver are > > running in > > >> different containers. > > > > > > I suspect it's not feasible. > > > > > > At a minimum, the Pacemaker container needs to run corosync as > > well as > > > pacemaker (implying a custom pid 1 script that starts both) and > > needs > > > to be privileged. I'm not sure corosync has been successfully > > > containerized before. > > > > > > Bundles won't work because they can only run on Pacemaker nodes. > > > > > > The db container could be configured as a remote node, basically > > > reproducing how a bundle is created internally. The db container > > would > > > be configured with pacemaker-remoted as its pid 1, and an IP > > given to > > > it that both pacemaker containers can reach. Launching all the > > > containers would need to be done by the OS at boot or manually. > > > > > > An ocf:pacemaker:remote resource would be configured in the > > cluster to > > > allow the pacemaker containers to manage the db via pacemaker- > > remoted > > > in the db containers. > > > > > > A custom fence agent would be needed to allow a pacemaker > > container to > > > ask the VM to reboot (kill and relaunch) any other container. > > Each VM > > > > Actually there is fence_docker which should work in this case. > > > > > and VM host would become a single point of failure unless a > > pacemaker > > > container could fence the VM and then the host as fallback fence > > > mechanisms in a topology. > > > > > > E.g. try to fence the container -> if that fails, try to fence > > the VM > > > -> if that fails, try to fence the host. Without all of that > > working, > > > something becomes a single point of failure. > > > > > > A preferred setup would be to run corosync and pacemaker on the > > VMs, > > > and configure bundles for the db containers. > > > > > >> > > >> Checked remote node,bundle concepts in Pacemaker unable to make > > HA > > >> setup work. > > >> > > >> Please let me know whether the above scenario can be handled, > > any > > >> links, examples would be of great help. > > >> > > >> Attaching a picture that depicts the scenario. > > >> > > >> Please do the needful, Thank you > > >> > > >> Regards > > >> Sridhar > > > > > > > _______________________________________________ > > Manage your subscription: > > https://lists.clusterlabs.org/mailman/listinfo/users > > > > ClusterLabs home: https://www.clusterlabs.org/ > > _______________________________________________ > Manage your subscription: > https://lists.clusterlabs.org/mailman/listinfo/users > > ClusterLabs home: https://www.clusterlabs.org/ -- Ken Gaillot <kgail...@redhat.com> _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/users ClusterLabs home: https://www.clusterlabs.org/