Detailed specifications, Raid, Caching – Dot Hill Systems SANnet II 200 User Manual
Page 24: Raid c, Aching

Detailed Specifications
RAID
RAID levels
0, 1, 0+1, 3, 5, 1+0, 3+0 and 5+0. Enhanced RAID Levels
supported with logical volume implementation.
Maximum number of logical drives
8
RAID level dependency to each logical
drive
Independent. Logical drive configured in different RAID levels
can co-exist in an array
Maximum number of drives for each logical
drive
31 (RAID 3 or 5); 45 (RAID 0 or NRAID); 44 (RAID 0+1)
Logical drive identification
Unique, controller randomly generated logical drive ID; Logical
drive name user-configurable
Maximum partitions of each logical drive
32
Maximum number of logical drives in a
logical volume
8
Maximum number of logical volumes
8
Maximum number of LUN per host ID
Up to 32, user configurable
Concurrent I/O
Supported
Tag command queuing
Supported
Dedicated spare drive
Supported
Global spare drive
Supported
Co-existing dedicated and global spare
drives
Supported
Auto-rebuild onto spare drive
Supported
Auto-scan of replacement drive upon
manually initiated rebuild
Supported
Auto-rebuild onto failed drive replacement
Supported. With no spare drive assigned, the controller will auto-
scan the failed drive and starts to rebuild automatically once the
failed drive has been replaced.
Background firmware download
Firmware can be downloaded during active I/Os. Administrator
may find appropriate time to reset controller later.
Auto recovery from logical drive failure
Supported.
Caused when a user accidentally removes the wrong disk and
causes a 2
nd
disk failure of a logical drive with one previously
failed disk
Caching
Write-back cache
Supported
Write-through cache
Supported
24