<div dir="auto"><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Hello,<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">I’m planning to setup a two node (active-passive) HA cluster consisting of pacemaker, corosync and DRBD. The two nodes will run on VMware VM’s and connect to a single DB server (unfortunately for various reasons not included in the cluster).  <u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Resources:<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Resource Group: clusterd_services<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     otrs_articel_fs    (ocf::heartbeat:Filesystem):    Started srv2<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     vip        (ocf::heartbeat:IPaddr2):       Started srv2<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     Apache     (systemd:httpd):        Started srv2<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     OTRS       (systemd:otrs): Started srv2<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Master/Slave Set: articel_ms [articel_drbd]<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     Masters: [ srv2 ]<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">     Slaves: [ srv1 ]<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">my_vcentre-fence       (stonith:fence_vmware_soap):    Started srv1<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Ultimately I would do<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="margin:0cm 0cm 0.0001pt 36pt;font-size:11pt;font-family:calibri,sans-serif"><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">-<span style="font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:7pt;line-height:normal;font-family:"times new roman"">       </span></span><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">Each VM will be running on separate ESXi hosts to provide at least a certain type of protection against hardware failure;<u></u><u></u></span></p><p style="margin:0cm 0cm 0.0001pt 36pt;font-size:11pt;font-family:calibri,sans-serif"><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">-<span style="font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:7pt;line-height:normal;font-family:"times new roman"">       </span></span><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">Redundant communication paths between the two nodes for DRBD replication and cluster communication to prevent split-brain scenarios;<u></u><u></u></span></p><p style="margin:0cm 0cm 0.0001pt 36pt;font-size:11pt;font-family:calibri,sans-serif"><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">-<span style="font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:7pt;line-height:normal;font-family:"times new roman"">       </span></span><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">fence_vmware_soap for VM fencing;<u></u><u></u></span></p><p style="margin:0cm 0cm 0.0001pt 36pt;font-size:11pt;font-family:calibri,sans-serif"><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">-<span style="font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:7pt;line-height:normal;font-family:"times new roman"">       </span></span><u></u><span style="font-size:10pt;font-family:'arial',sans-serif">pacemaker , corosync, pcsd not configured to start on both so that in case of a fence event they will not join the cluster but give room to investigate why it got fenced in first place;<u></u><u></u></span></p><pre style="white-space:pre-wrap;margin:0cm 0cm 0.0001pt 36pt;font-size:10pt;font-family:"courier new""><u></u><span style="font-family:'arial',sans-serif">-<span style="font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:7pt;line-height:normal;font-family:"times new roman"">       </span></span><u></u><span style="font-family:'arial',sans-serif">/usr/lib/drbd/<a href="http://crm-fence-peer.9.sh/" style="text-decoration-line:none;color:rgb(66,133,244)">crm-fence-peer.9.sh</a>  and /usr/lib/drbd/<a href="http://crm-unfence-peer.9.sh/" style="text-decoration-line:none;color:rgb(66,133,244)">crm-unfence-peer.9.sh</a> for DRBD resource level fencing (if the DRBD replication link becomes disconnected, the <a href="http://crm-fence-peer.9.sh/" style="text-decoration-line:none;color:rgb(66,133,244)">crm-fence-peer.9.sh</a> script contacts the cluster manager, determines the Pacemaker Master/Slave resource associated with this DRBD resource, and ensures that the Master/Slave resource no longer gets promoted on any node other than the currently active one);<u></u><u></u></span></pre><pre style="white-space:pre-wrap;margin:0cm 0cm 0.0001pt;font-size:10pt;font-family:"courier new""><u></u> <u></u></pre><pre style="white-space:pre-wrap;margin:0cm 0cm 0.0001pt;font-size:10pt;font-family:"courier new""><u></u> <u></u></pre><pre style="white-space:pre-wrap;margin:0cm 0cm 0.0001pt;font-size:10pt;font-family:"courier new""><u></u> <u></u></pre><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">What I’m just wondering is that if for whatever reason the communication paths between both nodes are interrupted so that each will think that the other node is gone, each of them will try to fence each other resulting in a fence race. I was reading that you could possibly introduce a delay into the secondary’s fencing for example 30-60 seconds so that during that delay, ASSUMING the primary is functioning well, the primary will fence the secondary, but that doesn’t sound like a reliable solution to me, I mean how can I assume before which one is primary and which one will suffer problems?<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Any sugestions?<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">I highly appreciate you effort!<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif"><u></u> <u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">BR,<u></u><u></u></span></p><p style="font-family:sans-serif;font-size:12.8px"><span style="font-size:10pt;font-family:'arial',sans-serif">Adam</span></p></div>