Solstice DiskSuite/Solaris Volume Manager Configuration Example

The following example helps to explain the process for determining the number of disk drives to place in each diskset. In this example, three storage devices are used. Existing applications are run over NFS (two file systems of 5 Gbytes each) and two ORACLE databases (one 5 Gbytes and one 10 Gbytes).

The following table shows the calculations that are used to determine the number of disk drives needed in the sample configuration. In a configuration with three storage devices, you would need 28 disk drives, which would be divided as evenly as possible among each of the three storage devices. Note that the 5-Gbyte file systems were given an additional 1 Gbyte of disk space because the number of disk drives needed was rounded up.

Table 3–2 Determining the Number of Disk Drives Needed for a Configuration

Use	Data	Disk Storage Needed	Disk Drives Needed
nfs1	5 Gbytes	3x2.1 Gbyte disks * 2 (Mirror)	6
nfs2	5 Gbytes	3x2.1 Gbyte disks * 2 (Mirror)	6
SPARC: oracle1	5 Gbytes	3x2.1 Gbyte disks * 2 (Mirror)	6
SPARC: oracle2	10 Gbytes	5x2.1 Gbyte disks * 2 (Mirror)	10

The following table shows the allocation of disk drives among the two disksets and four data services.

Table 3–3 Division of Disksets

Diskset	Data Services	Disk Drives	Storage Device 1	Storage Device 2	Storage Device 3
dg-schost-1	nfs1, oracle1	12	4	4	4
dg-schost-2	nfs2, oracle2	16	5	6	5

Initially, four disk drives on each storage device (a total of 12 disks) are assigned to dg-schost-1, and five or six disk drives on each (a total of 16 disks) are assigned to dg-schost-2.

No hot spare disks are assigned to either diskset. A minimum of one hot spare disk per storage device per diskset enables one drive to be hot spared, which restores full two-way mirroring.