Compaq Infortrend Global and Local Spare Drives, 9 Local Dedicated Spare, 10 Global Spare

1.4Spare Drives

Global and Local Spare Drives

Figure 1 - 9 Local (Dedicated) Spare

			When one member
Local	1	2	drive fails, the Local
			Spare Drive joins the
Spare	X		logical drive and
Drive			automatically starts
		3	to rebuild.

Local Spare Drive is a standby drive assigned to serve one specified logical drive. When a member drive of this specified logical drive fails, the Local Spare Drive becomes a member drive and automatically starts to rebuild.

Logical Drive

Global Spare Drive	Global Spare Drive
GS	GS

1	2	1	2	1	2
	3			4	3
Logical Drive 0		Logical Drive 1		Logical Drive 2

Figure 1 - 10 Global Spare

Global Spare Drive not only serves one specified logical drive. When a member drive from any of the logical drive fails, the Global Spare Drive will join that logical drive and automatically starts to rebuild.

Global Spare Drives serve any logical drive.

Figure 1 - 11 Global Spare Rebuild

The external RAID controllers provide both Local Spare Drive and Global Spare Drive functions. On certain occasions, applying these two functions together will better fit various needs. Take note though that the Local Spare Drive always has higher priority than the Global Spare Drive.

When a member drive from any logical drive fails, the Global Spare Drive joins that logical drive and automatically starts to rebuild.

1-6 Functional Description