The disk pools you select to geographically mirror must be in the same switchable hardware group. If you want to geographically mirror disk pools in more than one switchable hardware group, you need to complete the wizard one time for each switchable hardware group.
You have now configured geographic mirroring. Starting switchable hardware group to prepare the independent disk pool for use in this environment.
Print your disk configuration in case a recovery situation. Also, record the relationship between the independent disk pool name and number.
To start switchable hardware group, follow these steps.
- Start the switchable hardware group to enable device resiliency for the switchable hardware group.
- Make a disk pool available. To access the disk units in an independent disk pool make the disk pool available (vary on) the disk pool.
- Wait for resync to complete.
- Perform a test switchover. Before you add data to the disk pool, perform a test switchover to ensure the backup node can become the primary node and the primary node can become the backup node.
If you remove a node from a device domain after you configure geographic mirroring, the removed node takes any production copies or mirror copies that it owns. These nodes are changed to nongeographic mirrored disk pools.
You can also use CL commands and APIs for creating a switchable independent disk pool, however there are some tasks that require that you use iSeries Navigator.
To configure your geographic mirroring with the CL commands and APIs, follow these steps:
- Plan and configure your data port TCP/IP routes on all nodes in the recommended manner as follows:
- Node A should have routes to C and D.
- Node B should have routes to C and D.
- Node C should have routes to A and B.
- Node D should have routes to A and B.
- Create the cluster with the nodes that you want using the CRTCLU (Create Cluster) command.
- Start the nodes in the cluster using the STRCLUNOD (Start Cluster Node)
command.
- Create the device domain. You must create the device domain for all nodes involved in switching an independent disk pool using the ADDDEVDMNE (Add Device Domain Entry) command.
- Create the device descriptions. Device descriptions must be created on each node that will be in the cluster resource group (CRG). Use the CRTDEVASP (Create Device Description (ASP)) command. On the command line in the character-based interface, enter CRTDEVASP. In the Resource Name and the Device Description fields, enter the name of the independent disk pool you plan to create.
- Create the cluster resource group. Create the device CRG with the nodes,
their roles in the recovery domain, and the independent disk pool device descriptions.
You must also specify a site name and data port IP addresses for each node in the recovery domain. Use the CRTCRG (Create Cluster Resource Group) command.
- Create a disk pool on the node that owns the disk units using the New Disk Pool wizard when the system is fully restarted. Make sure clustering is active before you start. Name the independent disk pool to match the device description resource name. As you add disk units, it is best to localize disk units in the same expansion unit or IOP. Also, do not spread the disk pool across parity sets (iSeries Navigator required).
- Follow these steps to configure geographic mirroring:
- In iSeries Navigator, expand My Connections (or your active environment).
- Expand the System i™ you want to examine,Configuration and Service > Hardware > Disk Units > Disk Pools.
- Right-click the Disk Pool you want to mirror and select Geographic Mirroring > Configure Geographic Mirroring.
- Follow the wizard's instructions to configure geographic mirroring.
The disk pools you select to geographically mirror must be in the same switchable hardware group. If you want to geographically mirror disk pools in more than one switchable hardware group, you will need to complete the wizard one time for each switchable hardware group.
- Print your disk configuration in case of a recovery situation. See how to display your disk configuration in Backup and Recovery. Also, record the relationship between the independent disk pool name and number.
- Start the cluster resource group to enable device resiliency using the STRCRG (Start Cluster Resource Group) command.
- To access the disk units in an independent disk pool, vary on the disk pool using the VRYCFG (Vary Configuration) command. Vary on will also reconnect connections, so that any new route definitions can take effect.
- Before you add data to the disk pool, use the CHGCRGPRI (Change CRG Primary)
command to perform a test switchover. Use the test switchover to ensure the backup node can become the primary node and the primary node can become the backup node. .
Parent topic:
Configuring geographic mirroring with switchable independent disk pools
Related concepts
How geographic mirroring works Communications requirements