Specifications

Chapter 1 Introduction
5
SCSI Termination and Firmware
Termination: Active termination on the SCSI bus conforms to Alternative 2 of
the SCSI-2 specifications. Termination enable/disable is automatic through cable
detection.
Firmware: The HP NetRAID-1M and 2M firmware handles all RAID and SCSI
command processing and also supports the following functions:
• Disconnect/Reconnect feature optimizes SCSI Bus seek.
• Tagged Command Queuing allows multiple commands to be sent to the
controller, thus improving random access.
• Scatter/Gather supports multiple address/count pairs.
• Multi-threading supports up to 255 simultaneous commands with elevator
sorting and concatenation of requests per SCSI channel.
• Stripe size for each logical drive can be set from 2 KB to 128 KB.
• Multiple rebuilds and consistency checks have user-definable priority.
New Features of HP NetRAID-1M and 2M Adapters
New features of HP NetRAID-1M and 2M adapters include:
• Ultra3 SCSI support, with transfer rates up to 160 MB/sec for each
channel
• Greater number of disks per logical drive. All the physical disks attached
to an adapter can now be combined into one logical drive—up to 12 disks
for the HP NetRAID-1M and up to 24 disks for the two-channel NetRAID
2M. Older HP NetRAID adapters supported up to eight physical disks per
logical drive.
• RAID configurations containing up to 40 logical devices are now allowed
with both the HP NetRAID-1M and 2M. Older HP NetRAID adapters
supported up to eight logical drives.
• Enhanced Array Spanning
• Support for Clustering (HP NetRAID-2M only)