User Guide
4. Overview
4.4 SATA Differences and Limitations
4.4
SATA Differences and Limitations
This section describes the differences between the SAS and SATA versions of the 2U24 Flash Storage
Platform.
The 2U24 Flash Storage Platform has a variety of SKUs available that can be referenced in
. Some of the SKUs available leverage SAS based SSDs, and others reference SATA based
SSDs. The following is a list of general differences of SATA to the SAS versions.
•
SATA based SKUs only come with a single ESM. SAS SKUs come with redundant ESMs.
•
The SAS based drives are capable of 12Gbps transfer rates, while SATA is limited to 6Gbps
•
The SATA devices are limited to a single initiator when referenced by host devices.
4.4.1
SATA Single Initiator Limitation
The ATA protocol is not capable of handling multi-initiator access which means the 2U24 Flash Storage
Platform only supports a single SATA affiliation to one initiator. If multiple initiators are connected to an
enclosure with SATA devices installed then the initiator that first discovers the SATA device will be given
the affiliation to that SATA device. This creates a scenario where it is hard to control which initiator has
access to specific SATA devices within the enclosure. If multiple initiators must be used with a SATA
enclosure then zone the enclosure so each host port on the ESM only has access to a specific number of
SATA devices within the enclosure. This will prevent any variability in the device discovery process.
4.5
List of Replaceable Components
Table 4:
Replaceable Components
Component
Part Number
ESM
1EX0333
Dummy Carrier, Drive Blank
1EX0332
PSU
1EX0334
Standard Rail Kit (30in. maximum extension) w/ mounting
hardware
1EX0335
Extended Rail Kit (34in. maximum extension) w/ mounting
hardware
1EX2182
Rack Ear Bezel Kit
1EX0336
Power Cable C13-C14, 18AWG, 1.5m
1EX0084
Mini-SAS HD Cable, 3m
1EX0329
Chassis with Redundant ESMs, Redundant PSUs (SAS SKUs only)
1EX0338
Chassis with Single ESM, Redundant PSUs (SATA SKUs only)
1EX0285
Replacement Drive Carrier (No Drive) w/ screws
1EX0337
4.6
List of Compatible Drives
15