HP HA s Software manual # mkdir /dev/vgdatabase

Monitoring Disk Resources

Rules for Using the EMS Disk Monitor with MC/ServiceGuard

type of disk array you wish to configure, and follow the menus to define alternate links. Be sure to specify a different physical volume group for each link to the same disk.

The following example shows how to configure alternate links using LVM commands. In the example, the following disk configuration is assumed:

8/0.15.0 /dev/dsk/c0t15d0	/* I/O Channel 0 (8/0) SCSI address 15 LUN 0 */
8/0.15.1 /dev/dsk/c0t15d1	/* I/O Channel 0 (8/0) SCSI address 15 LUN 1 */
8/0.15.2 /dev/dsk/c0t15d2	/* I/O Channel 0 (8/0) SCSI address 15 LUN 2 */
8/0.15.3 /dev/dsk/c0t15d3	/* I/O Channel 0 (8/0) SCSI address 15 LUN 3 */
8/0.15.4 /dev/dsk/c0t15d4	/* I/O Channel 0 (8/0) SCSI address 15 LUN 4 */
8/0.15.5 /dev/dsk/c0t15d5	/* I/O Channel 0 (8/0) SCSI address 15 LUN 5 */
10/0.3.0 /dev/dsk/c1t3d0	/* I/O Channel 1 (10/0) SCSI address 3 LUN 0 */
10/0.3.1 /dev/dsk/c1t3d1	/* I/O Channel 1 (10/0) SCSI address 3 LUN 1 */
10/0.3.2 /dev/dsk/c1t3d2	/* I/O Channel 1	(10/0) SCSI address 3	LUN 2	*/
10/0.3.3 /dev/dsk/c1t3d3	/* I/O Channel 1	(10/0) SCSI address 3	LUN 3	*/
10/0.3.4 /dev/dsk/c1t3d4	/* I/O Channel 1	(10/0) SCSI address 3	LUN 4	*/
10/0.3.5 /dev/dsk/c1t3d5	/* I/O Channel 1	(10/0) SCSI address 3	LUN 5	*/

Assume that the disk array has been configured, and that both the following device files appear for the same LUN (logical disk) when you run the ioscan command:

/dev/dsk/c0t15d0

/dev/dsk/c1t3d0

Use the following steps to configure a volume group for this logical disk:

1.First, set up the group directory for vgdatabase:

#mkdir /dev/vgdatabase

2.Next, create a control file named group in the directory /dev/vgdatabase, as follows:

#mknod /dev/vgdatabase/group c 64 0xhh0000

The major number is always 64, and the hexadecimal minor number has the form

0xhh0000

where hh must be unique to the volume group you are creating. Use an appropriate hexadecimal number that is available on your system, after the volume groups that are already configured. On a single system, this might be the next hexadecimal number, on a cluster, these number must be assigned cluster-wide, so it should be one of the hexadecimal numbers used in the cluster. Use the following command to display a list of existing volume groups:

#ls -l /dev/*/group

3.Use the pvcreate command on one of the device files associated with the LUN to define the LUN to LVM as a physical volume.

#pvcreate /dev/dsk/c0t15d0

It is only necessary to do this with one of the device file names for the LUN.

44 Chapter 2