Validations Made by the Data Replication Subsystem (Sun Cluster Geographic Edition Data Replication Guide for Hitachi TrueCopy and Universal Replicator)

Sun Cluster Geographic Edition Data Replication Guide for Hitachi TrueCopy and Universal Replicator

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Validations Made by the Data Replication Subsystem

When the Hitachi TrueCopy or Universal Replicator device group, configured as dev_group in the /etc/horcm.conf file, is added to a protection group, the data replication layer makes the following validations.

Validates that the horcmd daemon is running on at least one node in the Nodelist property of the protection group.
Checks that the path to the storage device exists from all the nodes that are specified in the Nodelist property. The storage device controls the new Hitachi TrueCopy or Universal Replicator device group.
The Hitachi TrueCopy and Universal Replicator device group properties that are specified in the geopg add-device-group command are validated as described in the following table.

Hitachi TrueCopy or Universal Replicator Device Group Property	Validation
`devicegroupname`	Checks that the specified Hitachi TrueCopy or Universal Replicator device group is configured on all of the cluster nodes that are specified in the `Nodelist` property.
`Fence_level`	If a pair is already established for this Hitachi TrueCopy or Universal Replicator device group, the data replication layer checks that the specified `Fence_level` matches the already established fence level. If a pair is not yet established, for example, if a pair is in the `SMPL` state, any `Fence_level` is accepted.

Hitachi TrueCopy or Universal Replicator Device Group Property

Validation

devicegroupname

Checks that the specified Hitachi TrueCopy or Universal Replicator device group is configured on all of the cluster nodes that are specified in the Nodelist property.

Fence_level

If a pair is already established for this Hitachi TrueCopy or Universal Replicator device group, the data replication layer checks that the specified Fence_level matches the already established fence level.

If a pair is not yet established, for example, if a pair is in the SMPL state, any Fence_level is accepted.

When a Hitachi TrueCopy or Universal Replicator device group is added to a protection group, a Sun Cluster resource is automatically created by this command. This resource monitors data replication. The name of the resource is r-tc-protectiongroupname-devicegroupname. This resource is placed in the corresponding Sun Cluster resource group, which is named rg-tc-protectiongroupname.

Caution –

You must use caution before you modify these replication resources with Sun Cluster commands. These resources are for internal implementation purposes only.