On 15.03.2022 21:53, john tillman wrote: >> On 15.03.2022 19:35, john tillman wrote: >>> Hello, >>> >>> I'm trying to guarantee that all my cloned drbd resources start on the >>> same node and I can't figure out the syntax of the constraint to do it. >>> >>> I could nominate one of the drbd resources as a "leader" and have all >>> the >>> others follow it. But then if something happens to that leader the >>> others >>> are without constraint. >>> >> >> Colocation is asymmetric. Resource B is colocated with resource A, so >> pacemaker decides placement of resource A first. If resource A cannot >> run anywhere (which is probably what you mean under "something happens >> to that leader"), resource B cannot run anywhere. This is true also for >> resources inside resource set. >> >> I do not think pacemaker supports "always run these resources together, >> no matter how many resources can run". >>
This probably can be emulated by assigning high score less than INFINITY to colocation constraint. > > > Huh, no way to get all the masters to start on the same node. Interesting. > > The set construct has a boolean field "require-all". I'll try that before > I give up. > This applies to constraints external to the set, not to resources inside the set. > Could I create a resource (some systemd service) that all the masters are > colocated with? Feels like a hack but would it work? > Yes, of course. You could also make colocation based on node attribute and use some other means to set this attribute. > Thank you for the response. > > -John > > >>> I tried adding them to a group but got a syntax error from pcs saying >>> that >>> I wasn't allowed to add cloned resources to a group. >>> >>> If anyone is interested, it started from this example: >>> https://edmondcck.medium.com/setup-a-highly-available-nfs-cluster-with-disk-encryption-using-luks-drbd-corosync-and-pacemaker-a96a5bdffcf8 >>> There's a DRBD partition that gets mounted onto a local directory. The >>> local directory is then mounted onto an exported directory (mount >>> --bind). >>> Then the nfs service (samba too) get started and finally the VIP. >>> >>> Please note that while I have 3 DRBD resources currently, that number >>> may >>> increase after the initial configuration is performed. >>> >>> I would just like to know a mechanism to make sure all the DRBD >>> resources >>> are colocated. Any suggestions welcome. >>> >>> [root@nas00 ansible]# pcs resource >>> * Clone Set: drbdShare-clone [drbdShare] (promotable): >>> * Masters: [ nas00 ] >>> * Slaves: [ nas01 ] >>> * Clone Set: drbdShareRead-clone [drbdShareRead] (promotable): >>> * Masters: [ nas00 ] >>> * Slaves: [ nas01 ] >>> * Clone Set: drbdShareWrite-clone [drbdShareWrite] (promotable): >>> * Masters: [ nas00 ] >>> * Slaves: [ nas01 ] >>> * localShare (ocf::heartbeat:Filesystem): Started nas00 >>> * localShareRead (ocf::heartbeat:Filesystem): Started nas00 >>> * localShareWrite (ocf::heartbeat:Filesystem): Started nas00 >>> * nfsShare (ocf::heartbeat:Filesystem): Started nas00 >>> * nfsShareRead (ocf::heartbeat:Filesystem): Started nas00 >>> * nfsShareWrite (ocf::heartbeat:Filesystem): Started nas00 >>> * nfsService (systemd:nfs-server): Started nas00 >>> * smbService (systemd:smb): Started nas00 >>> * vipN (ocf::heartbeat:IPaddr2): Started nas00 >>> >>> [root@nas00 ansible]# pcs constraint show --all >>> Location Constraints: >>> Ordering Constraints: >>> promote drbdShare-clone then start localShare (kind:Mandatory) >>> promote drbdShareRead-clone then start localShareRead (kind:Mandatory) >>> promote drbdShareWrite-clone then start localShareWrite >>> (kind:Mandatory) >>> start localShare then start nfsShare (kind:Mandatory) >>> start localShareRead then start nfsShareRead (kind:Mandatory) >>> start localShareWrite then start nfsShareWrite (kind:Mandatory) >>> start nfsShare then start nfsService (kind:Mandatory) >>> start nfsShareRead then start nfsService (kind:Mandatory) >>> start nfsShareWrite then start nfsService (kind:Mandatory) >>> start nfsService then start smbService (kind:Mandatory) >>> start nfsService then start vipN (kind:Mandatory) >>> Colocation Constraints: >>> localShare with drbdShare-clone (score:INFINITY) >>> (with-rsc-role:Master) >>> localShareRead with drbdShareRead-clone (score:INFINITY) >>> (with-rsc-role:Master) >>> localShareWrite with drbdShareWrite-clone (score:INFINITY) >>> (with-rsc-role:Master) >>> nfsShare with localShare (score:INFINITY) >>> nfsShareRead with localShareRead (score:INFINITY) >>> nfsShareWrite with localShareWrite (score:INFINITY) >>> nfsService with nfsShare (score:INFINITY) >>> nfsService with nfsShareRead (score:INFINITY) >>> nfsService with nfsShareWrite (score:INFINITY) >>> smbService with nfsShare (score:INFINITY) >>> smbService with nfsShareRead (score:INFINITY) >>> smbService with nfsShareWrite (score:INFINITY) >>> vipN with nfsService (score:INFINITY) >>> Ticket Constraints: >>> >>> Thank you for your time and attention. >>> >>> -John >>> >>> >>> _______________________________________________ >>> 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/ >> >> > > > _______________________________________________ > 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/