Topology changes (add or drop CFs)

A cluster caching facility (CF) topology refers to the CFs that are part of a Db2® pureScale® instance. The CF topology refers to all CFs specified in the node configuration file (db2nodes.cfg).

Adding and dropping CFs can be performed online without having to bring down the entire Db2 pureScale cluster.

Note: All hosts in the cluster must be running at the same Db2 level in order to add or drop a CF. This applies for both online and offline operations.

Adding a new CF online

As in previous releases, adding a CF to the Db2 pureScale instance must be performed from a host member or cluster caching facility (CF) that is already part of the instance.

The new CF is added by using the db2iupdt command. When you add a CF to a member host with one or more members, the other members on the host need to be in STOPPED state.

A CF cannot be added to a host that already has a CF.

After the new CF is added, the instance is in the same state it was before the db2iupdt command was issued. The CF is not explicitly started as part of the add operation. The new CF must be started manually by using the db2start command.

Dropping a CF online

As in previous releases, dropping a CF from the Db2 pureScale instance must be performed from a host member or cluster caching facility (CF) that is already part of the instance.

A CF is dropped by using the db2iupdt command. There are no restrictions to dropping the secondary CF. However, if dropping the primary CF then the secondary CF must be in PEER state.