How to Mirror the Encapsulated Root Disk

After you install VxVM and encapsulate the root disk, perform this procedure on each node on which you mirror the encapsulated root disk.

Before You Begin

Ensure that you have encapsulated the root disk as described in SPARC: How to Encapsulate the Root Disk.

1. Become superuser.

2. List the devices.

   phys-schost# cldevice list -v

   Output looks similar to the following:

   DID Device Full Device Path ---------- ---------------- d1 phys-schost-1:/dev/rdsk/c0t0d0 d2 phys-schost-1:/dev/rdsk/c0t6d0 d3 phys-schost-2:/dev/rdsk/c1t1d0 d3 phys-schost-1:/dev/rdsk/c1t1d0

3. Mirror the encapsulated root disk.

   Follow the procedures in your VxVM documentation.

   For maximum availability and simplified administration, use a local disk for the mirror. See Guidelines for Mirroring the Root Disk for additional guidelines.

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   Caution –

   Do not use a quorum device to mirror a root disk. Using a quorum device to mirror a root disk might prevent the node from booting from the root-disk mirror under certain circumstances.

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4. View the node list of the raw-disk device group for the device that you used to mirror the root disk.

   The name of the device group is the form dsk/dN, where dN is the DID device name.

   phys-schost# cldevicegroup list -v dsk/dN

   -v

   Displays verbose output.

   Output looks similar to the following.

   Device group Type Node list ------------ ---- --------- dsk/dN Local_Disk phys-schost-1, phys-schost-3

5. If the node list contains more than one node name, remove from the node list all nodes except the node whose root disk you mirrored.

   Only the node whose root disk you mirrored should remain in the node list for the raw-disk device group.

   phys-schost# cldevicegroup remove-node -n node dsk/dN

   -n node

   Specifies the node to remove from the device-group node list.

6. Enable the localonly property of the raw-disk device group, if it is not already enabled.

   When the localonly property is enabled, the raw-disk device group is used exclusively by the node in its node list. This usage prevents unintentional fencing of the node from its boot device if the boot device is connected to multiple nodes.

   phys-schost# cldevicegroup set -p localonly=true dsk/dN

   -p

   Sets the value of a device-group property.

   localonly=true

   Enables the localonly property of the device group.

   For more information about the localonly property, see the scconf_dg_rawdisk(1M) man page.

7. Repeat this procedure for each node in the cluster whose encapsulated root disk you want to mirror.

Example 5–1 Mirroring the Encapsulated Root Disk

The following example shows a mirror created of the root disk for the node phys-schost-1. The mirror is created on the disk c0t0d0, whose raw-disk device-group name is dsk/d2. Disk c1t1d0 is a multihost disk, so the node phys-schost-3 is removed from the disk's node list and the localonly property is enabled.

phys-schost# cldevice list -v
DID Device          Full Device Path
----------          ----------------
d2                  pcircinus1:/dev/rdsk/c0t0d0
…
Create the mirror by using VxVM procedures
phys-schost# cldevicegroup  list -v dsk/d2
Device group        Type                Node list
------------        ----                ---------
dsk/d2              Local_Disk          phys-schost-1, phys-schost-3
phys-schost# cldevicegroup remove-node -n phys-schost-3 dsk/d2
phys-schost# cldevicegroup set -p localonly=true dsk/d2

Next Steps

Create disk groups. Go to Creating Disk Groups in a Cluster.