The JanusRAID2 SA-8850S is a single controller, U320 SCSI to SATA-II RAID storage subsystem. In a compact 4U - 24 bay chassis, featuring hot-swappable power supplies and fans. The RAID controller, fans, and power supplies are modularized allowing for easy removal from the rear of the unit. Also featuing a CGI-based GUI allowing easy remote configuration and monitoring using a web browser.
Innovate New Array Structure
The JanusRAID2 series features a new innovate array structure that hierarchically organizes storage objects. With this structure, physical drives are combined into Disk Groups (DG). Disk Groups are subdivided into Logical Disks (LD) where arrays are created. Lastly, Logical Disk can be combined or stripped together to form Volumes. Either volumes or LD can be pointed to a LUN which are then presented to the host computer.
Online Expansion and Defragmentation of Disk Groups
New physical disks can be added by expansion of a Disk Group (DG) while the unit remains online. During the process of expanding Disk Groups, defragmentation can be selected to move unused capacity to the ending LBA of a Disk Group. Defragmentation can also be selected at anytime there is unused storage space residing between Logical Disks.
Online Expansion and Shrinking of Logical Disks
Logical Disk (LD) Online Expansion can increase the capacity of an online LUN, instead of having to create a separate partition for unused capacity or capacity gained from Disk Group Expansion; now your storage can dynamically grow as your demands grow. In the event of overestimating requirements for Logical Disk capacity, shrinking can be used reduce the allocated storage of a Logical Disk.
Array Recovery Utility
The JanusRAID2 series now provides an Array Recovery Utility (ARU) that can aid a user in the event of multiple drive failures corrupting the RAID array of a Logical Disk and/or volumes. The ARU enables users to recover lost disk members of a Disk Group, and will automatically recover Logical Disks and Volumes.
Global or local spare disk
With the new JanusRAID2 storage structure, local and global spares can be configured. Local spares will belong to specific Disk Groups and will only replace faulty drives in a specific Disk Group. Meanwhile, Global Spares will replace faulty disk in any available Disk Group.
A simplified feature of Disk Scrubbing (DS), Regenerate Parity will regenerate the parity of a Logical Disk(s) in a Disk Group without a parity check.
Dual Flash ROM
Dual Flash ROM per controller gives higher RAID system availability and reliability during firmware upgrading or in the event of a single ROM failure.
Embedded CGI-based GUI (graphic user interface) management interface can be accessed through a web browser. The GUI allows users to easily setup RAID arrays, lun mapping, etc. and also provides remote monitoring of drive health, fan, and power supplies.
RAID 6 improves over the industry standard RAID 5 by adding another parity disk which gives greater reliability and data protection.
Disk Self Test (DST)
Before the release of this function, users of RAID systems were forced to test suspected bad hard drives in a host computer individually using a drive manufacturer’s utility. This function tests the health of hard drives with them installed in the RAID unit. DST performs write tests, servo analysis, and read scan tests; the test results are then displayed on the LCD and hyper terminal output. This can aid the user in deciding whether or not to replace a suspected failing hard drive. We highly recommend running this test before initializing a RAID set to ensure a healthy RAID solution.
Disk Scrubbing (DS)
With today’s RAID subsystems being capable of storing multiple terabytes, it is becoming increasingly difficult to manage and maintain that large amount of data. To aid a user in maintaining their data’s health, Arena-MaxTronic has released their newest firmware function Disk Scrubbing. The data and/or parity stored on hard drives can sometimes become corrupted; this data can also reside in areas that are not accessed for long periods of time. DS will use idle time to test the disks, and if a sector is found to be corrupted, the data will be regenerated from other RAID member disks and will be written to an uncorrupted sector. The purpose of DS is to prevent the possibility of having multiple corrupted sectors in a single stripe, which is one of the main causes of data loss.
Disk Clone (DC)
Hard drives are the most likely component to fail in a RAID array, and almost impossible to predict when the failure will occur. When a failure does occur the RAID unit will have to regenerate data from the non-failed hard drives to rebuild a new drive, and the RAID array will be in degraded mode. Having a unit in degraded mode is a very cautious time because if a second hard drive was to fail the RAID is destroyed and data is lost. This is where Disk Cloning can aide a user. With the help of the hard drives built in S.M.A.R.T. function, DC can determine when to begin cloning a bad drive to a hot spare. Upon completion of cloning, the new cloned disk can take the position of the failing disk or can stand-by until the original disk fails, then take the failed disks position. Disk cloning is to prevent a rebuild from ever occurring and having the unit in degraded mode.
Support for greater than 2TB LUN
Two firmware options are available to surpass the 2 terabyte limitation; 16byte CDB and variable sector size. With either of these functions enabled, users are able to create slices and map LUNs greater than 2TB to their respective host channels. See support documentation for compatibility or contact technical support for more information.
Initialization occurs during creation of a RAID array by zeroing out / formatting drives. By default the initialization process occurs with the unit offline, and inaccessible. With background initialization, the RAID array can be accessed during the initialization process so that the unit can be setup without having to wait several hours to complete initialization.
An optional BBU can be included in the RAID system to ensure data integrity in the event of a power outage. The BBU, or battery backup unit, will provide power to the on-board cache of the RAID controller in the event of a power outage. This will allow any data that is still stored on the cache to be saved until power is restored. Once power is restored, the RAID controller will flush the cache to drives.