Solaris Volume Manager Administration Guide

ProcedureHow to Replace a Submirror

Before You Begin

Read Overview of Replacing and Enabling Components in RAID-1 and RAID-5 Volumes and Creating and Maintaining RAID-1 Volumes.

  1. Make sure that you have root privilege and that you have a current backup of all data.

  2. Use the metastat command to view the status of the RAID-1 volume and associated submirrors.

    # metastat mirror-name
  3. Use one of the following methods to replace a submirror.

    • From the Enhanced Storage tool within the Solaris Management Console, open the Volumes node. Choose the mirror. Then, choose Action⇒Properties and click the Submirror tab. Follow the onscreen instructions. For more information, see the online help.

    • Use the metadetach, metaclear, metatinit, and metattach commands to replace an entire submirror.

      1. Use the metadetach command to the failed submirror from the mirror.

        # metadetach -f mirror-name submirror

        Forces the detach to occur


        Specifies the name of the mirror


        Specifies the submirror to detach

      2. Use the metaclear command to delete the submirror.

        # metaclear -f submirror

        Forces the deletion of the submirror to occur


        Specifies the submirror to delete

      3. Use the metainit command to create a new submirror.

        # metainit volume-name number-of-stripes components-per-stripe component-name

        Specifies the name of the volume to create. For information on naming volumes, see Volume Names.


        Specifies the number of stripes to create.


        Specifies the number of components each stripe should have.


        Specifies the names of the components that are used. This example uses the root slice, c0t0d0s0.

      4. Use the metattach command to attach the new submirror.

        # metattach mirror submirror

Example 11–19 Replacing a Submirror in a Mirror

The following example illustrates how to replace a submirror in an active mirror.

# metastat d20
d20: Mirror
    Submirror 0: d21
      State: Okay        
    Submirror 1: d22
      State: Needs maintenance
# metadetach -f d20 d22
d20: submirror d22 is detached
# metaclear -f d22
d22: Concat/Stripe is cleared
# metainit d22 2 1 c1t0d0s2 1 c1t0d1s2
d22: Concat/Stripe is setup
# metattach d20 d22
d20: components are attached

In this example, the metastat command confirms that the two-way mirror, d20, has a submirror, d22, in the “Needs maintenance” state. In this case, the entire submirror needs to be cleared and recreated. The metadetach command detaches the failed submirror from the mirror by using the -f option, which forces the detachment to occur. The metaclear command clears the submirror. The metainit command recreates submirror, d22, with new slices. Finally, the metattach command attaches the rebuilt submirror. A mirror resynchronization begins automatically.

The specific configuration of the new volume, d22, depends on the component you are replacing. A concatenation, as shown here, can sufficiently replace a concatenation. However, a concatenation would not be an ideal replacement for a stripe because it could impact performance.

You temporarily lose the capability for data redundancy while the mirror is a one-way mirror.