Oracle® Solaris Cluster Geographic Edition Data Replication Guide for EMC Symmetrix Remote Data Facility

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Updated: July 2014, E39668-01
 
 

Configuring Data Replication With SRDF Software on the Primary Cluster

This section describes the steps you must perform on the primary cluster before you can configure SRDF data replication with Geographic Edition software. The following information is in this section:

Setting Up SRDF Device Groups

SRDF devices are configured in pairs. The mirroring relationship between the pairs becomes operational as soon as the SRDF links are online. If you have dynamic SRDF available, you have the capability to change relationships between R1 and R2 volumes in your device pairings on the fly without requiring a BIN file configuration change.


Note -  Do not configure a replicated volume as a quorum device. Locate any quorum devices on a shared, unreplicated volume or use a quorum server.

The EMC Symmetrix database file on each host stores configuration information about the EMC Symmetrix units attached to the host. The EMC Symmetrix global memory stores information about the pair state of operating EMC SRDF devices.

EMC SRDF device groups are the entities that you add to Geographic Edition protection groups to enable the Geographic Edition software to manage EMC Symmetrix pairs.

The SRDF device group can hold one of two types of devices:

  • RDF1 source device, which acts as the primary

  • RDF2 target device, which acts as the secondary

As a result, you can create two types of SRDF device group, RDF1 and RDF2. An SRDF device can be moved to another device group only if the source and destination groups are of the same group type.

You can create RDF1 device groups on a host attached to the EMC Symmetrix software that contains the RDF1 devices. You can create RDF2 device groups on a host attached to the EMC Symmetrix software that contains the RDF2 devices. You can perform the same SRDF operations from the primary or secondary cluster, using the device group that was built on that side.

When you add remote data facility devices to a device group, all of the devices must adhere to the following restrictions:

  • The device must be an SRDF device.

  • The device must be either an RDF1 or RDF2 type device, as specified by the device group type.

  • The device must belong to the same SRDF group number.

  • The SRDF device group configuration must be the same on all nodes of both the primary and secondary clusters. For example, if you have a device group DG1, which is configured as RDF1, on node1 of clusterA, then node2 of clusterA should also have a device group called DG1 with the same disk set. Also, clusterB should have an SRDF device group called DG1, which is configured as RDF2, defined on all nodes.

Checking the Configuration of SRDF Devices

Before adding SRDF devices to a device group, use the symrdf list command to list the EMC Symmetrix devices configured on the EMC Symmetrix units attached to your host.

# symrdf list

By default, the command displays devices by their EMC Symmetrix device name, a hexadecimal number that the EMC Symmetrix software assigns to each physical device. To display devices by their physical host name, use the pd argument with the symrdf command.

# symrdf list pd

How to Create an RDF1 Device Group

The following steps create a device group of type RDF1 and add an RDF1 EMC Symmetrix device to the group.

  1. Create a device group named devgroup1.
    phys-paris-1# symdg create devgroup1 -type rdf1
  2. Add an RDF1 device, with the EMC Symmetrix device name of 085, to the device group on the EMC Symmetrix storage unit identified by the number 000000003264.

    A default logical name of the form DEV001 is assigned to the RDF1 device.

    phys-paris-1# symld -g devgroup1 -sid 3264 add dev 085

Next Steps

Create the Geographic Edition device groups, file systems, or ZFS storage pools you want to use, specifying the LUNs in the SRDF device group. You also need to create an HAStoragePlus resource for the device group, file system, or ZFS storage pool you use.

If you create a ZFS storage pool, observe the following requirements and restrictions:

  • Mirrored and unmirrored ZFS storage pools are supported.

  • ZFS storage pool spares are not supported with storage-based replication in a Geographic Edition configuration. The information about the spare that is stored in the storage pool results in the storage pool being incompatible with the remote system after it has been replicated.

  • ZFS can be used with either Synchronous or Asynchronous mode. If you use Asynchronous mode, ensure that SRDF is configured to preserve write ordering, even after a rolling failure.

For more information about creating device groups, file systems, and ZFS storage pools in a cluster configuration, see Oracle Solaris Cluster System Administration Guide . For information about creating an HAStoragePlus resource, see Oracle Solaris Cluster Data Services Planning and Administration Guide .