Sun Cluster Software Installation Guide for Solaris OS

ProcedureHow to Create a Disk Set

Perform this procedure to create disk sets.

  1. SPARC: (Solaris 9) Determine whether, after you create the new disk sets, the global cluster will have more than three disk sets.

    • If the cluster will have no more than three disk sets, skip to Step 9.

    • If the cluster will have four or more disk sets, proceed to Step 2 to prepare the cluster. You must perform this task whether you are installing disk sets for the first time or whether you are adding more disk sets to a fully configured cluster.

    • If the cluster runs on the Solaris 10 OS, Solaris Volume Manager automatically makes the necessary configuration changes. Skip to Step 9.

  2. On any node of the cluster, check the value of the md_nsets variable in the /kernel/drv/md.conf file.

  3. If the total number of disk sets in the cluster will be greater than the existing value of md_nsets minus one, increase the value of md_nsets to the desired value.

    The maximum permissible number of disk sets is one less than the configured value of md_nsets. The maximum possible value of md_nsets is 32, therefore the maximum permissible number of disk sets that you can create is 31.

  4. Ensure that the /kernel/drv/md.conf file is identical on each node of the cluster.

    Caution – Caution –

    Failure to follow this guideline can result in serious Solaris Volume Manager errors and possible loss of data.

  5. If you made changes to the md.conf file on any node, perform the following steps to make those changes active.

    1. On one node, become superuser.

    2. From one node, shut down the cluster.

      phys-schost# cluster shutdown -g0 -y
    3. Reboot each node of the cluster.

      • On SPARC based systems, do the following:

        ok boot
      • On x86 based systems, do the following:

        When the GRUB menu is displayed, select the appropriate Solaris entry and press Enter. The GRUB menu appears similar to the following:

        GNU GRUB version 0.95 (631K lower / 2095488K upper memory)
        | Solaris 10 /sol_10_x86                                                  |
        | Solaris failsafe                                                        |
        |                                                                         |
        Use the ^ and v keys to select which entry is highlighted.
        Press enter to boot the selected OS, 'e' to edit the
        commands before booting, or 'c' for a command-line.

        For more information about GRUB based booting, see Chapter 11, GRUB Based Booting (Tasks), in System Administration Guide: Basic Administration.

  6. On each node in the cluster, run the devfsadm(1M) command.

    You can run this command on all nodes in the cluster at the same time.

  7. From one node of the cluster, update the global-devices namespace.

    phys-schost# cldevice populate

    See the cldevice(1CL) man page for more information.

  8. On each node, verify that the command has completed processing before you attempt to create any disk sets.

    The command executes remotely on all nodes, even though the command is run from just one node. To determine whether the command has completed processing, run the following command on each node of the cluster.

    phys-schost# ps -ef | grep scgdevs
  9. Ensure that the disk set that you intend to create meets one of the following requirements.

    • If the disk set is configured with exactly two disk strings, the disk set must connect to exactly two nodes and use exactly two mediator hosts. These mediator hosts must be the same two hosts used for the disk set. See Configuring Dual-String Mediators for details on how to configure dual-string mediators.

    • If the disk set is configured with more than two disk strings, ensure that for any two disk strings S1 and S2, the sum of the number of drives on those strings exceeds the number of drives on the third string S3. Stated as a formula, the requirement is that count(S1) + count(S2) > count(S3).

  10. Ensure that the local state database replicas exist.

    For instructions, see How to Create State Database Replicas.

  11. Become superuser on the cluster node that will master the disk set.

  12. Create the disk set.

    The following command creates the disk set and registers the disk set as a Sun Cluster device group.

    phys-schost# metaset -s setname -a -h node1 node2
    -s setname

    Specifies the disk set name.


    Adds (creates) the disk set.

    -h node1

    Specifies the name of the primary node to master the disk set.


    Specifies the name of the secondary node to master the disk set

    Note –

    When you run the metaset command to configure a Solaris Volume Manager device group on a cluster, the command designates one secondary node by default. You can change the desired number of secondary nodes in the device group by using the clsetup utility after the device group is created. Refer to Administering Device Groups in Sun Cluster System Administration Guide for Solaris OS for more information about how to change the numsecondaries property.

  13. If you are configuring a replicated Solstice DiskSuite or Solaris Volume Manager device group, set the replication property for the device group.

    phys-schost# cldevicegroup sync device-group-name

    For more information about data replication, see Chapter 4, Data Replication Approaches, in Sun Cluster System Administration Guide for Solaris OS.

  14. Verify the status of the new disk set.

    phys-schost# metaset -s setname
  15. As needed, set device group properties.

    phys-schost# cldevicegroup set -p name=value devicegroup

    Specifies a device-group property.


    Specifies the name of a property.


    Specifies the value or setting of the property.


    Specifies the name of the device group. The device-group name is the same as the disk-set name.

    See the cldevicegroup(1CL) for information about device-group properties.

Example 4–6 Creating a Disk Set

The following command creates two disk sets, dg-schost-1 and dg-schost-2, with the nodes phys-schost-1 and phys-schost-2 specified as the potential primaries.

phys-schost# metaset -s dg-schost-1 -a -h phys-schost-1 phys-schost-2
phys-schost# metaset -s dg-schost-2 -a -h phys-schost-1 phys-schost-2

Next Steps

Add drives to the disk set. Go to Adding Drives to a Disk Set.