Technical information

June 2012 Dell EqualLogic Configuration Guide v13.2 17
Table 7 PS Series Firmware Compatibility
Firmware V5.2.x
Firmware V5.1.x
Firmware V5.0.x
Firmware V4.3.x
SAN HeadQuarters
2.2.x
2.1.x
2.2.x
2.1.x
2.2.x
2.1.x
2.2.x
2.1.x
Host Integration Tools
for Microsoft
4.0.x
3.5.x
4.0.x
3.5.x
4.0.x
3.5.x
3.4.x
3.3.x
4.0.x
3.5.x
3.4.x
3.3.x
Host Integration Tools
for VMware
3.1.x
3.0.x
3.1.x
3.0.x
2.0.x
3.1.x
3.0.x
2.0.x
2.0.x
EqualLogic Storage
Replication Adapter
for VMware Site
Recovery Manager
2.1.x
2.0.x
1.0.x
2.1.x
2.0.x
1.0.x
2.1.x
2.0.x
1.0.x
1.0.x
EqualLogic
Multipathing
Extension Module for
VMware vSphere
1.1.x
1.0.x
1.1.x
1.0.x
1.1.x
1.0.x
1.1.x
1.0.x
Host Integration Tools
for Linux
1.1.x
1.0.x
1.1.x
1.0.x
1.1.x
1.0.x
1.0.x
Manual Transfer
Utility
1.2.1 1.2.1 1.2.1
1.1.2 (Windows
only)
1.0.2 (Linux only)
1.2.1
1.1.2 (Windows
only)
1.0.2 (Linux only)
2.4 RAID Policies and Sizing Tables
Each array in an EqualLogic array group is configured with a single RAID policy. Arrays (or group
members) within the same storage pool that have the same RAID policy will cooperatively work to
host volumes by distributing those volumes over multiple arrays. Two things that are defined by the
RAID policy are:
• RAID level
• hot-spare configuration
Each array implements a default RAID policy that includes a hot-spare. To configure a RAID policy that
does not include a hot-spare, you must manually initialize the array using the Command Line
Interface.
Note: Configuring a RAID policy that does not include a hot-spare will increase the risk of data
loss in the event of multiple drive failures.
2.4.1 RAID 5 Drive Layouts and Total Usable Storage
RAID 5 (striped disks with distributed parity) will combine N disks in an arrangement where each stripe
consists of N–1 disks that contain data blocks plus 1 disk that contains a parity block. For each stripe,
the parity block will be placed on a different disk ensuring that the parity blocks are not located on a
single disk in the RAID set. RAID 5 implementations can tolerate a single drive failure without data loss.