Validations That Occur Before a Takeover

When a takeover is initiated by using the geopg takeover command, the data replication subsystem runs several validations on both clusters. These steps are conducted on the original primary cluster only if the primary cluster can be reached. If validation on the original primary cluster fails, the takeover still occurs.

First, the replication subsystem checks that the Hitachi TrueCopy or Universal Replicator device group is in a valid aggregate device group state. Then, the replication subsystem checks that the local device group states on the target primary cluster, cluster-newyork, are not 32 or 52. These values correspond to a SVOL_COPY state, for which the horctakeover command fails. The Hitachi TrueCopy or Universal Replicator commands that are used for the takeover are described in the following table.

Table 3–2 Hitachi TrueCopy or Universal Replicator Takeover Validations on the New Primary Cluster

Aggregate Device Group State	Valid Local State Device Group State	Hitachi TrueCopy or Universal Replicator Takeover Commands That Are Run on cluster-newyork
SMPL	All	No command is run.
Regular primary	All	No command is run.
Regular secondary	All Regular secondary states except 32 or 52  For a list of Regular secondary states, refer to Table 2–1 and Table 2–2.	horctakeover -S -g dg [-t] The-t option is given when the fence_level of the Hitachi TrueCopy or Universal Replicator device group is async. The value is calculated as 80% of the Timeout property of the protection group. For example, if the protection group has a Timeout of 200 seconds, the value of -t used in this command will be 80% of 200 seconds, or 160 seconds.
Takeover primary	All	No command is run.
Takeover secondary	All	pairsplit -R-g dg pairsplit -S-g dg