Key Features
Innovate New Array StructureThe 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.
JBOD Expansion
This newly added feature provides users the
option to attach a JBOD unit to expand the
capacity of their Arena Maxtronic storage
solution. By allowing the SA-6651E to
control the RAID-less JBOD units helps
reduce the total cost of ownership.
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.
Regenerate Parity
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.
Web-based GUI
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
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.
Background Initialization
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.
BBU
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.
