How the State of the Hitachi TrueCopy or Universal Replicator Device Group Is Validated

For validation purposes, Sun Cluster Geographic Edition gives each Hitachi TrueCopy or Universal Replicator device group a state according to the current state of its pair. This state is returned by the pairvolchk -g devicegroup -ss command.

The remainder of this section describes the individual device group states and how these states are validated against the local role of the protection group.

Determining the State of an Individual Hitachi TrueCopy or Universal Replicator Device Group

An individual Hitachi TrueCopy or Universal Replicator device group can be in one of the following states:

• SMPL

• Regular Primary

• Regular Secondary

• Takeover Primary

• Takeover Secondary

The state of a particular device group is determined by using the value that is returned by the pairvolchk -g devicegroup -ss command. The following table describes the device group state associated with the values returned by the pairvolchk command.

Determining the Aggregate Hitachi TrueCopy or Universal Replicator Device Group State

If a protection group contains only one Hitachi TrueCopy or Universal Replicator device group, then the aggregate device group state is the same as the individual device group state.

When a protection group contains multiple Hitachi TrueCopy or Universal Replicator device groups, the aggregate device group state is obtained as described in the following table.

The aggregate device group state cannot be obtained for any other combination of individual device group states. This is considered a pair-state validation failure.

Validating the Local Role of the Protection Group Against the Aggregate Device Group State

The local role of a Hitachi TrueCopy or Universal Replicator protection group is validated against the aggregate device group state as described in the following table.

Example 2–12 Validating the Aggregate Device Group State

This example validates the state of a Hitachi TrueCopy or Universal Replicator device group against the role of the Hitachi TrueCopy or Universal Replicator protection group to which it belongs.

First, the protection group is created as follows:

phys-paris-1# geopg create -s paris-newyork-ps -o primary -d truecopy tcpg

A device group, devgroup1, is added to the protection group, tcpg, as follows:

phys-paris-1# geopg add-device-group -p fence_level=async devgroup1 tcpg

The current state of a Hitachi TrueCopy or Universal Replicator device group, devgroup1, is provided in the output of the pairdisplay command as follows:

phys-paris-1# pairdisplay -g devgroup1 
Group PairVol(L/R) (Port#,TID,LU),Seq#,LDEV#,P/S,Status,Fence,Seq#,P-LDEV# M 
devgroup1 pair1(L) (CL1-A , 0, 1) 12345   1..P-VOL PAIR ASYNC,54321  609   -
devgroup1 pair1(R) (CL1-C , 0, 20)54321 609..S-VOL PAIR ASYNC,-----   1    - 
devgroup1 pair2(L) (CL1-A , 0, 2) 12345   2..P-VOL PAIR ASYNC,54321  610   - 
devgroup1 pair2(R) (CL1-C , 0,21) 54321 610..S-VOL PAIR ASYNC,-----   2    -

The pairvolchk -g <DG> -ss command is run and returns a value of 23.

phys-paris-1# pairvolchk -g devgroup1 -ss
parivolchk : Volstat is P-VOL.[status = PAIR fence = ASYNC]
phys-paris-1# echo $?
23

The output of the pairvolchk command is 23, which corresponds in Table 2–1 to an individual device group state of Regular Primary. Because the protection group contains only one device group, the aggregate device group state is the same as the individual device group state. The device group state is valid because the local role of the protection group, specified by the -o option, is primary, as specified in Table 2–3.