8.2 Unmirroring a Mirrored SBD Partition with NLVM

Use the procedure in this section to remove the mirrored segment from a mirrored SBD partition, and then to remove the single element mirror from the SBD. This leaves a single device that contains an SBD partition.

  1. Log in to any node as the root user, then launch a terminal console.

  2. Delete the mirrored segment from the mirrored SBD partition. At the command prompt, enter

    nlvm [--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.

    For example, to delete segment 1 of the cluster1.sbd RAID1 device, enter

    nlvm delete raid cluster1.sbd segment 1

  3. View a list of partitions and verify that the SBD partition named <cluster_name>.msbd1 has been deleted. At the command prompt, enter

    nlvm list partitions

  4. View a list of RAIDs and verify that the SBD RAID1 device <cluster_name>.sbd still exists. At the command prompt, enter

    nlvm list raids

  5. Delete the single element mirror from the SBD. At the command prompt, enter

    nlvm [--no-prompt] delete raid <raid_name>

    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.

    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. The SBD partition is renamed from <cluster_name>.msbd0 to <cluster_name>.sbd, and the RAID1 device <cluster_name>.sbd is deleted.

  6. View a list of RAIDs and verify that the SBD RAID1 device <cluster_name>.sbd has been removed. At the command prompt, enter

    nlvm list raids

  7. 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 list partitions

    For example, the SBD partition entry is now:

    cluster1.sbd device=sdc type=1AD(Cluster) start=32 size=99.59MB(203968)