Validations Made by the Data Replication Subsystem (Sun Cluster Geographic Edition System Administration Guide)

Sun Cluster Geographic Edition System Administration Guide

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Validations Made by the Data Replication Subsystem

When the Hitachi TrueCopy 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 all of the nodes given in the Nodelist property of the protection group.

For more information about the horcmd daemon, see the Sun StorEdge SE 9900 V Series Command and Control Interface User and Reference Guide
Checks that the path to the storage device exists from all of the nodes given in the Nodelist property. The storage device controls the newHitachi TrueCopy device group.
The Hitachi TrueCopy device group properties specified in the geopg add-device-group command are validated as described in the following table.

Hitachi TrueCopy Device Group Property	Validation
`device-group-name`	Checks that the specified Hitachi TrueCopy 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 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 Device Group Property

Validation

device-group-name

Checks that the specified Hitachi TrueCopy 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 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 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-protection-group-name-device-group-name. This resource is placed in the corresponding Sun Cluster resource group, which is named rg-tc-protection-group-name.

Caution –

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