Cluster reconfiguration occurs if a node leaves or joins a cluster. Each node's cluster monitor continuously watches the other cluster nodes. When the membership of the cluster changes, the cluster monitor informs VxVM for it to take appropriate action.
During cluster reconfiguration, VxVM suspends I/O to shared disks. I/O resumes when the reconfiguration completes. Applications may appear to freeze for a short time during reconfiguration.
If other operations, such as VxVM operations or recoveries, are in progress, cluster reconfiguration can be delayed until those operations have completed. Volume reconfigurations do not take place at the same time as cluster reconfigurations. Depending on the circumstances, an operation may be held up and restarted later. In most cases, cluster reconfiguration takes precedence. However, if the volume reconfiguration is in the commit stage, it completes first.
See "Volume reconfiguration" on page 390.
See "vxclustadm utility" on page 388.
vxclustadm command provides an interface to the cluster functionality of VxVM when VCS is used as the cluster monitor. It is also called during cluster startup and shutdown. In the absence of a cluster monitor,
vxclustadm can also be used to activate or deactivate the cluster functionality of VxVM on any node in a cluster.
startnode keyword to
vxclustadm starts cluster functionality on a cluster node by passing cluster configuration information to the VxVM kernel. In response to this command, the kernel and the VxVM configuration daemon,
vxconfigd, perform initialization.
stopnode keyword stops cluster functionality on a node. It waits for all outstanding I/O to complete and for all applications to close shared volumes.
abortnode keyword terminates cluster activity on a node. It does not wait for outstanding I/O to complete nor for applications to close shared volumes.
reinit keyword allows nodes to be added to or removed from a cluster without stopping the cluster. Before running this command, the cluster configuration file must have been updated with information about the supported nodes in the cluster.
nidmap keyword prints a table showing the mapping between node IDs in VxVM's cluster-support subsystem and node IDs in the cluster monitor. It also prints the state of the node in the cluster.
nodestate keyword reports the state of a cluster node and also the reason for the last abort of the node as shown in this example:
state: out of cluster
reason: user initiated stop
Node abort messages lists the various reasons that may be given for a node abort.
vxclustadm(1M) manual page.