Skip Navigation Links
Exit Print View
| Oracle Solaris Cluster Geographic Edition Data Replication Guide for Hitachi TrueCopy and Universal Replicator

Search Scope:

- This Document
- Entire Library

## Administering Hitachi TrueCopy and Universal Replicator Data Replication Device Groups

This section provides the following information about administering Hitachi TrueCopy and Universal Replicator data replication device groups:

- How to Add a Data Replication Device Group to a Hitachi TrueCopy or Universal Replicator Protection Group

- Validations Made by the Data Replication Subsystem

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

- How to Modify a Hitachi TrueCopy or Universal Replicator Data Replication Device Group

- How to Delete a Data Replication Device Group From a Hitachi TrueCopy or Universal Replicator Protection Group

For details about configuring a Hitachi TrueCopy or Universal Replicator data replication protection group, see How to Create and Configure a Hitachi TrueCopy or Universal Replicator Protection Group That Does Not Use Oracle Real Application Clusters.

## How to Add a Data Replication Device Group to a Hitachi TrueCopy or Universal Replicator Protection Group

1. Log in to a cluster node.

   You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Geographic Edition Software and RBAC in Oracle Solaris Cluster Geographic Edition System Administration Guide.

2. Create a data replication device group in the protection group.

   This command adds a device group to a protection group on the local cluster and propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.

       # geopg add-device-group -p property [-p...] devicegroupname protectiongroupname

   `-p` property

     Specifies the properties of the data replication device group.

     You can specify the `Fence_level` property which defines the fence level that is used by the device group. The fence level determines the level of consistency among the primary and secondary volumes for that device group.

     You can set this property to `data`, `status`, `never`, or `async`. When you use a `Fence_level` of `never` or `async`, the application can continue to write to the primary cluster even after failure on the secondary cluster. However, when you set the `Fence_level` property to `data` or `status`, the application on the primary cluster might fail because the secondary cluster is not available for the following reasons:

     - Data replication link failure

     - Secondary cluster and storage is down

     - Storage on the secondary cluster is down

     | Caution - To avoid application failure on the primary cluster, specify a `Fence_level` of `never` or `async`. If you specify a `Fence_level` of `never`, the data replication roles do not change after you perform a takeover. If you have special requirements to use a `Fence_level` of `data` or `status`, consult your Oracle representative.

     The other properties you can specify depend on the type of data replication you are using. For details about these properties, see Appendix A, Standard Geographic Edition Properties, in Oracle Solaris Cluster Geographic Edition System Administration Guide.

   devicegroupname

     Specifies the name of the new data replication device group.

   protectiongroupname

     Specifies the name of the protection group that will contain the new data replication device group.

   For information about the names and values that are supported by Geographic Edition software, see Appendix B, Legal Names and Values of Geographic Edition Entities, in Oracle Solaris Cluster Geographic Edition System Administration Guide.

   For more information about the `geopg` command, refer to the `geopg`(1M) man page.

Example 2-11 Adding a Data Replication Device Group to a Hitachi TrueCopy or Universal Replicator Protection Group

This example creates a Hitachi TrueCopy or Universal Replicator data replication device group in the `tcpg` protection group.

    # geopg add-device-group -p Fence_level=data devgroup1 tcpg

### 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.

When a Hitachi TrueCopy or Universal Replicator device group is added to a protection group, a Oracle Solaris 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 Oracle Solaris Cluster resource group, which is named `rg-tc-`protectiongroupname.

| Caution - You must use caution before you modify these replication resources with Oracle Solaris Cluster commands. These resources are for internal implementation purposes only.

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

For validation purposes, 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.

Table 2-1 Individual Hitachi TrueCopy and Universal Replicator Device Group States

Output of `pairvolchk` | Individual Device Group State
--- | ---
`11 = SMPL` | `SMPL`
`22 / 42 = PVOL_COPY` `23 / 42 = PVOL_PAIR` `26 / 46 = PVOL_PDUB` `47 = PVOL_PFUL` `48 = PVOL_PFUS` | `Regular Primary`
`24 / 44 = PVOL_PSUS` `25 / 45 = PVOL_PSUE` For these return codes, determining the individual device group category requires that the `horcmd` process be active on the remote cluster so that the `remote-pair-state` for this device group can be obtained. | `Regular Primary`, if `remote-cluster-state !=SSWS` or `Takeover Secondary`, if `remote-cluster-state == SSWS` `SSWS`, when you use the `pairdisplay -g devicegroup -fc` command.
`32 / 52 = SVOL_COPY` `33 / 53 = SVOL_PAIR` `35 / 55 = SVOL_PSUE` `36 / 56 = SVOL_PDUB` `57 = SVOL_PFUL` `58 = SVOL_PFUS` | `Regular Secondary`
`34 / 54 = SVOL_PSUS` | `Regular Secondary`, if `local-cluster-state !=SSWS` or `Takeover Primary`, if `local-cluster-state == SSWS` `SSWS`, when you use the `pairdisplay -g devicegroup -fc` 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.

Table 2-2 Conditions That Determine the Aggregate Device Group State

Condition | Aggregate Device Group State
--- | ---
All individual device group states are `SMPL` | `SMPL`
All individual device group states are either `Regular Primary` or `SMPL` | `Regular Primary`
All individual device group states are either `Regular Secondary` or `SMPL` | `Regular Secondary`
All individual device group states are either `Takeover Primary` or `SMPL` | `Takeover Primary`
All individual device group states are either `Takeover Secondary` or `SMPL` | `Takeover Secondary`

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.

Table 2-3 Validating the Aggregate Device Group State Against the Local Role of a Protection Group

Aggregate Device Group State | Valid Local Protection Group Role
--- | ---
`SMPL` | `primary` or `secondary`
`Regular Primary` | `primary`
`Regular Secondary` | `secondary`
`Takeover Primary` | `primary`
`Takeover Secondary` | `secondary`

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.

## How to Modify a Hitachi TrueCopy or Universal Replicator Data Replication Device Group

1. Log in to a cluster node.

   You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Geographic Edition Software and RBAC in Oracle Solaris Cluster Geographic Edition System Administration Guide.

2. Modify the device group.

   This command modifies the properties of a device group in a protection group on the local cluster. Then the command propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.

       # geopg modify-device-group -p property [-p...] TCdevicegroupname protectiongroupname

   `-p` property

     Specifies the properties of the data replication device group.

     For more information about the properties you can set, see Appendix A, Standard Geographic Edition Properties, in Oracle Solaris Cluster Geographic Edition System Administration Guide.

   TCdevicegroupname

     Specifies the name of the new data replication device group.

   protectiongroupname

     Specifies the name of the protection group that will contain the new data replication device group.

Example 2-13 Modifying the Properties of a Hitachi TrueCopy or Universal Replicator Data Replication Device Group

This example modifies the properties of a data replication device group that is part of a Hitachi TrueCopy or Universal Replicator protection group.

    # geopg modify-device-group -p fence_level=async tcdg tcpg

## How to Delete a Data Replication Device Group From a Hitachi TrueCopy or Universal Replicator Protection Group

Before You Begin

You might delete a data replication device group from a protection group if you added a data replication device group to a protection group. Normally, after an application is configured to write to a set of disks, you would not change the disks.

Deleting a data replication device group does not stop replication or change the replication status of the data replication device group.

For information about deleting protection groups, refer to How to Delete a Hitachi TrueCopy or Universal Replicator Protection Group. For information about deleting application resource groups from a protection group, refer to How to Delete an Application Resource Group From a Hitachi TrueCopy or Universal Replicator Protection Group.

1. Log in to a cluster node.

   You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Geographic Edition Software and RBAC in Oracle Solaris Cluster Geographic Edition System Administration Guide.

2. Remove the device group.

   This command removes a device group from a protection group on the local cluster. Then the command propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.

       # geopg remove-device-group devicegroupname protectiongroupname

   devicegroupname

     Specifies the name of the data replication device group

   protectiongroupname

     Specifies the name of the protection group

   When a device group is deleted from a Hitachi TrueCopy or Universal Replicator protection group, the corresponding Oracle Solaris Cluster resource, `r-tc-`protectiongroupname`-`devicegroupname, is removed from the replication resource group. As a result, the deleted device group is no longer monitored. The resource group is removed when the protection group is deleted.

Example 2-14 Deleting a Replication Device Group From a Hitachi TrueCopy or Universal Replicator Protection Group

This example removes a Hitachi TrueCopy or Universal Replicator data replication device group.

    # geopg remove-device-group tcdg tcpg

Copyright © 2004, 2011, Oracle and/or its affiliates. All rights reserved. Legal Notices |