Lenovo ThinkServer RD240 Software User's Manual page 44

2.4.13.1 Global Hot Spare
2.4.13.2 Dedicated Hot Spare
2-12
If the hot spare is designated as having enclosure affinity, it will attempt
to rebuild any failed drives on the backplane that it resides in before
rebuilding any other drives on other backplanes.
Note: If a rebuild to a hot spare fails for any reason, the hot spare
drive will be marked as "failed". If the source drive fails,
both the source drive and the hot spare drive will be
marked as "failed".
There are two types of hot spares:
•
Global hot spare
•
Dedicated hot spare
A global hot spare drive can be used to replace any failed drive in a
redundant drive group as long as its capacity is equal to or larger than
the coerced capacity of the failed drive. A global hot spare defined on
any channel should be available to replace a failed drive on both
channels.
A dedicated hot spare can be used to replace a failed drive only in a
selected drive group. One or more drives can be designated as a
member of a spare drive pool. The most suitable drive from the pool is
selected for fail over. A dedicated hot spare is used before one from the
global hot spare pool.
Hot spare drives can be located on any RAID channel. Standby hot
spares (not being used in RAID drive group) are polled every 60 seconds
at a minimum, and their status made available in the drive group
management software. RAID controllers offer the ability to rebuild with a
disk that is in a system, but not initially set to be a hot spare.
Observe the following parameters when using hot spares:
•
Hot spares are used only in drive groups with redundancy: RAID
levels 1, 5, 6, 10, 50, and 60.
•
A hot spare connected to a specific RAID controller can be used to
rebuild a drive that is connected to the same controller only.
Introduction to RAID