8.3 Deleting an SBD Partition with NLVM

You might need to delete and re-create a OES Cluster Services SBD partition if the SBD becomes corrupted or its device fails. Use the procedure in this section to delete the SBD partition, and then to create a new SBD partition by using one of the methods in Section 8.1, Creating or Mirroring an SBD Partition.

IMPORTANT:You must take the cluster down and stop OES Cluster Services on all nodes before you delete the existing SBD partition. Do not restart OES Cluster Services and rejoin nodes to the cluster until after you create a new SBD.

Ensure that nobody else is changing any storage on any nodes at this time.

Until the SBD exists and the cluster is set up for shared disk access, you are responsible for ensuring that you have exclusive access to the shared storage.
Take the cluster down:
1. Log in to any node in the cluster as the root user, then open a terminal console.
2. At the command prompt, enter
```
cluster down
```
On each cluster node, stop OES Cluster Services:
1. Log in to the cluster node as the root user, then open a terminal console.
2. At the command prompt, enter
```
rcnovell-ncs stop
```
3. After you have stopped OES Cluster Services on all nodes, continue with the next step.
Log in to any node in the cluster as the root user, then launch a terminal console.
If the SBD partition is mirrored, unmirror the SBD partition:
1. Delete the mirrored segment from the mirrored SBD partition. At the command prompt, enter
```
nlvm -s [--force] [--no-prompt] delete raid <raid_name> segment <segment_number>
```
  You are automatically prompted to confirm the delete action. Respond by typing yes or no, then press Enter. You can use the --no-prompt NLVM option to suppress the confirmation prompt.
  
  Replace raid_name with the name of the mirrored SBD RAID device that contains the segment to be deleted, such as cluster1.sbd. The RAID name is case sensitive.
  
  Replace segment_number with the segment index (zero relative) to be removed. For a mirrored SBD RAID the possible values are 0 and 1.
  
  Use the --force NLVM option to remove out-of-sync segments.
  
  Use the -s NLVM option to override the shared locking requirement and force the command to execute.
  
  For example, to delete segment 1 of the cluster1.sbd RAID1 device, enter
```
nlvm -s --force delete raid cluster1.sbd segment 1
```
2. Delete the single element mirror from the SBD. At the command prompt, enter
```
nlvm -s [--no-prompt] delete raid <raid_name>
```
  Because the RAID device is now a single element RAID1, this command removes the single element mirror from the SBD, and leaves the SBD partition on the device.
  
  You are automatically prompted to confirm the delete action. Respond by typing yes or no, then press Enter. You can use the --no-prompt NLVM option to suppress the confirmation prompt.
  
  Replace raid_name with the name of the mirrored SBD RAID device that contains the segment to be deleted, such as cluster1.sbd. The RAID name is case sensitive.
  
  Use the -s NLVM option to override the shared locking requirement and force the command to execute.
  
  For example, to delete the single element mirror from the cluster1.sbd device, enter
```
nlvm -s delete raid cluster1.sbd
```
3. View a list of RAIDs and verify that the SBD RAID1 device <cluster_name>.sbd has been removed. At the command prompt, enter
```
nlvm -s list raids
```
  Use the -s NLVM option to override the shared locking requirement and force the command to execute.
4. View a list of partitions and verify that the SBD partition name has been changed from <cluster_name>.msbd0 to <cluster_name>.sbd. At the command prompt, enter
```
nlvm -s list partitions
```
  Use the -s NLVM option to override the shared locking requirement and force the command to execute.
  
  For example, the SBD partition entry is now:
```
cluster1.sbd device=sdc type=1AD(Cluster) start=32 size=99.59MB(203968)
```
Delete the SBD partition. At the command prompt, enter
```
nlvm -s delete partition <partition_name>
```
Replace partition_name with the name of the SBD partition, such as cluster1.sbd. The partition name is case sensitive.

Use the -s NLVM option to override the shared locking requirement and force the command to execute.

For example, to delete the single element mirror from the cluster1.sbd device, enter
```
nlvm -s delete partition cluster1.sbd
```
If you plan to reuse the device for the SBD, initialize and share the device. At the command prompt, enter
```
nlvm -s init <device_name> format=msdos shared
```
WARNING:Initializing a device destroys all data on the device.

Replace device_name with the leaf node name (such as sde) of the SAN device.

Specify a partitioning format of msdos.

Specify the shared option to mark the device as Shareable for Clustering.

Use the -s NLVM option to override the shared locking requirement and force the command to execute.

You can list the devices to visually verify that the device is formatted and shared:
```
nlvm -s list devices
```
To re-create the SBD partition, continue with Section 8.1, Creating or Mirroring an SBD Partition.

Do not restart OES Cluster services and rejoin nodes to the cluster until after you create the new SBD.