Restoring a Local Boot Disk From Backup

Some situations require you to replace a cluster node's boot disk, such as when a software problem leaves the boot disk in an unknown state, an operating system upgrade fails, or a hardware problem occurs. Use the following procedures to restore the boot disk to a known state, or to replace the disk.

These procedures assume the existence of a backup copy of the boot disk.

How to Restore a Local Boot Disk From Backup (Solstice DiskSuite)

When the physical hosts are in the same cluster, this procedure is performed on the local host while another host provides data services for all hosts. In this example, we use two physical hosts phys-hahost1 and phys-hahost2, and two logical hosts hahost1 and hahost2.

These are the high-level steps to restore a boot disk from backup in a Solstice DiskSuite configuration.

• Removing the host containing the boot disk from the disksets

• Restoring the boot disk from backup

• Renewing or creating replicas on the restored disk

• Adding the host back to the disksets

• Starting Sun Cluster on that host

• Switching over the logical host to its default master (if manual mode is set for switchback)

These are the detailed steps to restore a boot disk from backup in a Solstice DiskSuite configuration. In this example, phys-hahost1 contains the disk to be restored. The boot disk is not mirrored.

1. Halt the host requiring the restore.

2. On the other hosts in the cluster, use the metaset(1M) command to remove the host being restored from the disksets.

   In this example, the metaset(1M) command is run from the other host in the cluster, phys-hahost2.

   phys-hahost2# metaset -s hahost1 -f -d -h phys-hahost1 phys-hahost2# metaset -s hahost2 -f -d -h phys-hahost1

3. Restore the boot disk on the host being restored from the backup media.

   Follow the procedure to restore files and file systems, as found in your Solaris system administration documentation to restore the boot disk file system.

4. Reboot the host being restored.

5. Remove old DiskSuite replicas and reboot.

   If you are replacing a failed disk, old replicas will not be present. If you are restoring a disk, run the metadb(1M) command to check whether old replicas are present. If so, delete the old replicas.

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   Note -

   The default location for replicas is Slice 7. However, you are not required to place replicas on Slice 7.

   phys-hahost1# metadb -d -f c0t3d0s7 phys-hahost1# reboot

   ---

6. Create new DiskSuite replicas on the restored disk with the metadb(1M) command.

   phys-hahost1# metadb -afc 3 c0t3d0s7

7. Add the restored host to the diskset or disksets, from the sibling host.

   phys-hahost2# metaset -s hahost1 -a -h phys-hahost1 phys-hahost2# metaset -s hahost2 -a -h phys-hahost1

8. Start Sun Cluster on the restored host.

   phys-hahost1# scadmin startnode

9. Switch back the logical hosts to the default master, if necessary.

   If manual mode is not set, an automatic switchback will occur.

   phys-hahost1# haswitch phys-hahost1 hahost1

How to Restore a Local Boot Disk From Backup (VxVM)

When the physical hosts are in the same cluster, this procedure is performed on the local host while another host provides data services for all hosts. In this example, we use two physical hosts phys-hahost1 and phys-hahost2, and two logical hosts hahost1 and hahost2. In this example, the boot disk is not mirrored.

These are the high-level steps to restore a boot disk from backup in a VxVM configuration.

• Halting the host requiring the restore

• Restoring the boot disk from backup

• Starting Sun Cluster on that host

• Switching over the logical host to its default master (if manual mode is set for switchback)

These are the detailed steps to restore a boot disk from backup in a VxVM configuration. In this example, phys-hahost1 contains the disk to be restored.

1. Halt the host requiring the restore.

2. Restore the boot disk on the host being restored from the backup media.

   Follow the procedure to restore files and file systems as found in your Solaris system administration documentation to restore the boot disk file system.

3. Reboot the host being restored.

   The reboot causes the host to discover all the devices.

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   Note -

   If the disks are reserved, it may be necessary to run vxdctl enable at a later time, when reservations are released.

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4. Start Sun Cluster on the local host.

   phys-hahost1# scadmin startnode

5. Switch back the logical hosts to the default master, if necessary.

   If manual mode is not set, an automatic switchback will occur.

   phys-hahost1# haswitch phys-hahost1 hahost1