Planning for Changes in Cluster Size

If you intend to add additional nodes to the cluster online (while it is running) ensure that they are connected to the same heartbeat subnets and to the same lock disks as the other cluster nodes. For cross-subnet considerations, see “Cross-Subnet Configurations” (page 30).

In selecting a cluster lock configuration, be careful to anticipate any potential need for additional cluster nodes. Remember that a cluster of more than four nodes must not use a lock disk, but a two-node cluster must use a cluster lock. Thus, if you will eventually need five nodes, you should build an initial configuration that uses a Quorum Server.

If you intend to remove a node from the cluster configuration while the cluster is running, ensure that the resulting cluster configuration will still conform to the rules for cluster locks described above. See “Cluster Lock Planning” (page 98) for more information.

If you are planning to add a node online, and a package will run on the new node, ensure that any existing cluster bound volume groups for the package have been imported to the new node. Also, ensure that the MAX_CONFIGURED_PACKAGES parameter (see “Cluster Configuration Parameters ” is set high enough to accommodate the total number of packages you will be using.

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HP Serviceguard manual Planning for Changes in Cluster Size