Recover system procedure

The recover system procedure recovers the entire system if the system state is lost. The procedure re-creates the storage system by using saved configuration data and is also known as Tier 3 (T3) recovery. The saved configuration data is in the active quorum disk and the latest XML configuration backup file. The recovery might not be able to restore all volume data.

CAUTION:

If the system encounters a state where:

No nodes are active
Do not attempt to initiate a node rescue (which the user can initiate either by using the service assistant GUI, or the satask rescuenode service CLI command). STOP and contact IBM®® Remote Technical Support. Initiating this T3 recover system procedure while in this specific state can result in loss of the XML configuration backup files.

Attention:

Run service actions only when directed by the fix procedures. If used inappropriately, service actions can cause loss of access to data or even data loss. Read and understand all of the instructions before you complete any action.
The recovery procedure can take several hours if the system uses large-capacity devices as quorum devices.
If there are offline arrays after running the recovery procedure, contact IBM Support.

Do not attempt the recover system procedure unless the following conditions are met:

All of the conditions are met in When to run the recover system procedure.
All hardware errors are fixed. See Fix hardware errors
All nodes have candidate status. Otherwise, see step 1.
All nodes must be at the same level of code that the system had before the failure. If any nodes were modified or replaced, use the service assistant to verify the levels of code, and where necessary, to reinstall the level of code so that it matches the level that is running on the other nodes in the system. For more information, see Removing system information for nodes with error code 550 or error code 578 using the service assistant.
If the system was using IP quorum for T3 metadata, verify that all the IP quorum applications are running.

The system recovery procedure is one of several tasks that must be completed. The following list is an overview of the tasks and the order in which they must be completed:

Preparing for system recovery:
1. Review the information about when to run the recover system procedure.
2. Fix your hardware errors and make sure that all nodes in the system are shown in service assistant or in the output from sainfo lsservicenodes.
3. Remove the system information for nodes with error code 550 or error code 578 by using the service assistant, but only if the recommended user response for these node errors are followed.
4. For Virtual Volumes (VVols), shut down the services for any instances of Spectrum Control Base that are connecting to the system. Use the Spectrum Control Base command service ibm_spectrum_control stop.
5. Remove hot spare nodes from the system and set them into candidate mode before starting the recovery process. Run the following CLI command to remove the node from the system.
```
satask leavecluster -force spare-node-panel-name
```
  Once the node returns in service mode, run the following CLI command to set it into candidate mode.
```
satask stopservice spare-node-panel-name
```
Running the system recovery. After you prepared the system for recovery and met all the pre-conditions, run the system recovery.
Note: Run the procedure on one system in a fabric at a time. Do not run the procedure on different nodes in the same system. This restriction also applies to remote systems.
Completing actions to get your environment operational.
- Recovering from offline volumes by using the CLI.
- Checking your system, for example, to ensure that all mapped volumes can access the host.