E2128J JBOD FAQ & Document Download Page
Question: How to make use of the 2 Host Ports?
Answer: the application is to use 2 separate SAS RAID controllers with each connected to one of the IN-Ports/Host-Ports. Each controller will create RAID volume(s) over its own group of disks. Each disk will belong to one and only one RAID controller. Each RAID volume will belong to one and only one RAID controller. There is no disk or volume will cross two different RAID controllers.
These 2 SAS RAID controllers can be in two different computers or both in the same computer. When they are in two different computers, these two computers are Sharing the JBOD device without sharing the data. When both SAS RAID controllers are in the same computer, quite often, it is to use the OS to stripe/aggregate two RAID volumes for maximum data throughput.
There are two methods to achieve 2 IN-Ports: Zoning Disabled & Zoning Enabled.
Method-1: Zoning Disabled.
By default, the E2128J shipped with Zoning disable. This method requires SAS disks to be used and will not support SATA disks for 2 IN-Ports. Each SAS RAID controller will be able to see all SAS disks, one controller will create RAID volume over whichever disks to be included, and the other controller will create the RAID volume over the rest of disks.
Method-2: Zoning(PHY Zoning) Enabled
Zoning can be enabled by a simple command from hyperterminal via RS232 serial connection to the JBOD. When Zoning is enabled, it equally and logically divides the 12 disks into 6 disks per group for each IN-Port, one SAS RAID controller on one IN-Port won’t see the other 6 disks that belong to another IN-Port. This configuration will work for both SAS and/or SATA disks.
What the 2 IN-Ports Will NOT DO:
It does not support 2 Servers Clustering !
It does not support Path-Failover !
Question: What is the performance of E2128J ?
Answer: the E2128J enclosure itself is capable of delivering 1200MB/sec by design. However, performance question is more for the RAID controller instead of for the JBOD.
We did run some performance tests with Areca ARC-1680X connected to it and achieved some very high performance numbers:
799.1MB/sec Sequential Write & 680MB/sec Sequential Read - RAID-0
645.2MB/sec Sequential Write & 665MB/sec Sequential Read - RAID-5
634.0MB/sec Sequential Write & 677MB/sec Sequential Read - RAID-6
(performance could be further fine-tuned...it was done based on the 1680X with IOP348-800Mhz. The current 1680X has IOP348-1200MHz which will definitely improve performance)
Test Configurations:
12 x 1TB Hitachi SATA disk, 0A38016, 16MB cache. ST6OA31B firmware
Mac G5,
Dual 2GHz Processor, OS 10.5.6, 2GB memory
Areca ARC-1680X, PCIe SAS RAID adapter, firmware v1.46
Benchmark program:
AJA KONA System Test, Video Frame Size: 1920 x 1080 10Bit-RGB
Disable File System Cache
4GB file size
Question: why use Areca ARC-1680X for benchmarking ?
Answer: While the ARC-1680X is equally good as the other SAS RAID adapters from LSI, Intel, Adaptec for IT applications, we found the ARC-1680X has a more balanced Read/Write performance which are typically suitable for digital video editing applications, besides, ARC-1680X provides fine-tune options for HD/AV applications and works with Mac systems.
Question: How is the compatibility with hard disks ?
Answer: users should check the compatibility between the SAS RAID adapter and the disks. If the SAS RAID adapter and the disks are compatible, then they will work with the E2128J. For our own testing purposes, we have tested with Seagate's SAS and SATA disks, Hitachi SAS & SATA disks, and WD RE2 and RE3 disks.
Question: What can the LCD do ?
Answer: the E2128J supports staggering spin up the hard drives to prevent power over-draw at power up. The default time interval for staggering spin up is 3 seconds. The LCD allows the administrator to change the default value of 3 seconds.
The LCD also allows turnning on and off the audio alarm.
The LCD can display a lots of useful & critical information such as: Product name, Enclosure ID, Firmware version, Fan status, Power module status, Power voltage status, Hard drive temperature status, etc.
Question: Why showing critical events in the RAID eventlog is important?
Answer: one of the many E2128J's features is reporting enclosure events to the RAID adapter's eventlog on the host computer via SES. These events include but not limit to: power failure, fan failure, HDD over-temperature and HDD failure, etc.
Why is this so important? because in many cases, the administrator is not near where the storage/server is, and he/she can not see the warning LEDs and can not hear any audio warning beeps. The administrator is solely relying on pre-configured email notification for action-taking. If the critical event from the enclosure is not reported to the RAID adapter's eventlog, that means the administrator is not aware of what has went wrong, thus, no action taken until the system is completely down.
Question: How does it compare to other vendors' JBOD?
Question: How does it compare to PCIe-over-Cable ?
Product Features & Specifications.
Detail list of which SAS RAID adapters are compatible and how compatible they are.
A Must-Read before installing and using the JBOD unit.
Descripts where and how and why to set DIP switches on the IO Module.
Descripts where and how and why to set Enclosure ID