Backing up and restoring the cluster configuration

You can back up and restore the cluster configuration data after preliminary tasks are completed.

Cluster configuration data provides information about your cluster and the objects that are defined in it. The backup and restore functions of the svcconfig command can only back up and restore your cluster configuration data. You must regularly back up your application data using the appropriate backup methods.

Information about the following objects is included in the cluster configuration data:

Storage system
Hosts
I/O groups
Managed disks (MDisks)
MDisk groups
Nodes
Virtual disks (VDisks)
VDisk-to-host mappings
Users and user groups
FlashCopy® mappings
FlashCopy consistency groups
Metro Mirror relationships
Metro Mirror consistency groups
Global Mirror relationships
Global Mirror consistency groups

You can maintain your cluster configuration data by complete the following tasks:

Backing up the cluster configuration data
Restoring the cluster configuration data
Deleting unwanted backup configuration data files

Before you backup your cluster configuration data, the following prerequisites must be met:

No independent operations that change the cluster configuration can be running while the backup command is running.
No object name can begin with an underscore.

Note:

The default object names for controllers, I/O groups and managed disks (MDisks) do not restore correctly if the ID of the object is different than what is recorded in the current cluster configuration data file.
All other objects with default names are renamed during the restore process. The new names appear in the format name_r. Where name is the name of the object in your cluster.

Before you restore your cluster configuration data, the following prerequisites must be met:

You have the Security Administrator role associated with your username and password.
You have a copy of your backup cluster configuration files on a server that is accessible to the cluster.
You have a backup copy of your application data.
You know the current license settings for your cluster.
You have not removed any hardware since the last backup of your cluster configuration. If you had to replace a faulty node, the new node must use the same worldwide node name (WWNN) as the faulty node that it replaced.
Note: You can add new hardware, but you must not remove any hardware because the removal can cause the restore process to fail.
No zoning changes have been made on the fibre-channel fabric which would prevent communication between the SAN Volume Controller and with other nodes or storage controllers which are present in the configuration.

The restore must be performed to a single node cluster. You can restore the configuration using any node as the configuration node. However, if you do not use the node that was the configuration node when the cluster was first created, the unique identifier (UID) of the VDisks that are within the I/O groups can change. This can affect IBM® TotalStorage® Productivity Center for Fabric, VERITAS Volume Manager, and any other programs that record this information.

The SAN Volume Controller analyzes the backup configuration data file and the cluster to verify that the required disk controller system nodes are available.

Before you begin, hardware recovery must be complete. The following hardware must be operational: hosts, SAN Volume Controller, disk controller systems, disks, the Ethernet network, and the SAN fabric.