3.4 Creating Shared Disk Groups

Exercise 3: Create a shared disk group.

The command syntax is:

# vxdg -s init group_name device_name(s)

You can specify multiple device names in a single command. For example, you can add the two disks (two mirrored sets of one) in the group acct at one time:

# vxdg -s init acct c1t0d0 c2t0d0

The disks listed here were selected for convenience, because they occupy the same relative locations in the two SPARCstorage Array units.

If you select some other combination of locations, consider how this may complicate disk organization and maintenance.

You can check the results:

# vxdisk list

The acct disk group is a shared disk group. The term shared means that after another node joins the cluster, it will automatically import the acct disk group. The volumes can be accessed from both nodes.

The second set of disks on Controller c2 will be used as the mirror disks.

As an alternative to listing all devices in one command, you can start with a single device in a shareable disk group, then add more disks to that disk group. For example, to initialize a single device in a shareable disk group named acct:

# vxdg -s init acct c1t0d0

To add a second disk to the acct disk group:

# vxdg -g acct adddisk c2t0d0

Exercise 4: Continue by creating disk groups named history, admin_system, log_node1, and log_node2. Table 3-3 lists the total number of disks that you might use for each group. For simplicity in your exercises, use full disks (not partial disks).

To list the disk groups on your system, use vxdg list.

# vxdg list
rootdg	 enabled
acct 	enabled 	shared	 nnnnnnnnn.nnnn.node
admin_system	 enabled	 shared	 nnnnnnnnn.nnnn.node
history	enabled	 shared	 nnnnnnnnn.nnnn.node
log_node1	enabled	 shared	 nnnnnnnnn.nnnn.node
log_node2	enabled	shared 	nnnnnnnnn.nnnn.node

When you have created the disk groups, display the CVM configuration records.

# vxprint

This command lists all of the volume records on the system.

To examine a specific group, use the -g option.

# vxprint -g group_name