Solstice DiskSuite or Solaris Volume Manager Configuration Example

The following example helps to explain the process for determining the number of drives to place in each disk set. 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 drives that are needed in the sample configuration. In a configuration with three storage devices, you would need 28 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 drives needed was rounded up.

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

Use	Data	Disk Storage Needed	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 drives among the two disk sets and four data services.

Table 3–3 Division of Disk Sets

Disk Set	Data Services	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 drives on each storage device (a total of 12 drives) are assigned to dg-schost-1, and five or six drives on each (a total of 16 drives) are assigned to dg-schost-2.

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