Mirroring an encapsulated root disk

VxVM allows you to mirror the root volume and other areas needed for booting onto another disk. Mirroring the root volume enables you to recover from a failure of your root disk by replacing it with one of its mirrors.

For Sun x64 systems, mirroring a root disk creates a GRUB boot menu entry for the Primary and Alternate (mirror) Boot disk.

For Sun SPARC systems, after mirroring the root disk, you can configure the system to boot from the alternate boot drive to recover from a primary boot drive failure.

See the Storage Foundation High Availability Solutions Troubleshooting Guide for more information about recovering from boot drive failure.

To mirror your root disk onto another disk

  1. Choose a disk that is at least as large as the existing root disk.
  2. If the selected disk is not already under VxVM control, use the vxdiskadd or the vxdiskadm command to add it to the bootdg disk group. Ensure that you specify the sliced format for the disk.
  3. Select Mirror Volumes on a Disk from the vxdiskadm main menu to create a mirror of the root disk. Doing so automatically invokes the vxmirror command if the mirroring operation is performed on the root disk.

    Alternatively, to mirror only those file systems on the root disk that are required to boot the system, run the following command:

    # vxmirror boot_disk altboot_disk

    where altboot_disk is the disk media name of the mirror for the root disk. vxmirror creates a mirror for rootvol (the volume for the root file system on an alternate disk). The alternate root disk is configured to enable booting from it if the primary root disk fails.

  4. Monitor the progress of the mirroring operation with the vxtask list command.
    # vxtask list
       TASKID PTID TYPE/STATE PCT PROGRESS
       161 PARENT/R 0.00% 3/0(1) VXRECOVER dg01 dg
       162 162 ATCOPY/R 04.77% 0/41945715/2000896 PLXATT home home-01 dg