10.5. Cluster Services Hang

When the cluster services attempt to fence a node, the cluster services stop until the fence operation has successfully completed. Therefore, if your cluster-controlled storage or services hang and the cluster nodes show different views of cluster membership or if your cluster hangs when you try to fence a node and you need to reboot nodes to recover, check for the following conditions:
  • The cluster may have attempted to fence a node and the fence operation may have failed.
  • Look through the /var/log/messages file on all nodes and see if there are any failed fence messages. If so, then reboot the nodes in the cluster and configure fencing correctly.
  • Verify that a network partition did not occur, as described in Section 10.8, “Each Node in a Two-Node Cluster Reports Second Node Down”. and verify that communication between nodes is still possible and that the network is up.
  • If nodes leave the cluster the remaining nodes may be inquorate. The cluster needs to be quorate to operate. If nodes are removed such that the cluster is no longer quorate then services and storage will hang. Either adjust the expected votes or return the required amount of nodes to the cluster.

Note

You can fence a node manually with the fence_node command or with Conga. For information, see the fence_node man page and Section 5.3.2, “Causing a Node to Leave or Join a Cluster”.