Overland Storage SnapServer DX2
Lab Performance Test
The SnapServer DX2 delivered excellent results in our Lab Performance Tests.
SnapServer DX-series of NAS appliances
aim to take the strain out of provisioning network storage by automating the
entire process. A key feature of Overland's new GuardianOS 7 is DynamicRAID,
which allows you to mix and match hard disks of different capacities and makes
in the same array.
The drives are placed in a central storage pool, and you can
choose single or dual parity during its creation. Don't worry if you change your
mind afterwards, as you can swap between each one on the fly.
Capacity expansion is simple, as you just add more drives to
the pool as required and existing drives can also be swapped out for larger
ones, without incurring any downtime. There's room to expand outside the box, as
the SnapServer DX2 on review supports up to seven SnapExpansion disk shelves,
allowing total capacity to be increased to 288TB.
Thin provisioning is implemented on NAS volumes, which are
created within the storage pool and grow or shrink in size automatically as
demand dictates. If you wish, you can place quotas on selected NAS volumes to
limit their maximum size.
Deployment is swift, as the SnapServer Manager (SSM) discovers
the appliance on the network and provides quick access to its well designed web
interface. A wizard guides you through initial setup, which includes DynamicRAID
configuration where you choose single or dual parity and decide how much space
to keep aside for snapshots.
NAS volumes can have point-in-time snapshots assigned to them.
The impact of backup operations can be reduced, as a NAS share presents its own
snapshot as a separate public or private share that can be used as a backup
The CIFS/SMB, AFP, NFS and FTP protocols are all supported,
allowing Windows, Linux, Unix and Mac clients to access the appliance. Each
protocol can be enabled or disabled individually for each network share, and
access restrictions applied using the local user database or AD domain
Overland's Snap EDR (enterprise data replicator) software
increases value, as this allows selected shares to be synchronised with other
systems. You can distribute files from one source to multiple locations,
aggregate files from multiple sources to a single location, and replicate files
and folders between one source and one target. Overland offers optional agents
for Windows and Linux systems, allowing them to be included in the replication
IP SAN support is a standard feature and the appliance
supports up to 256 virtual volumes. Target creation is simple, as you take space
from the storage pool, enter a capacity for the target and activate CHAP
authentication, if required.
Full support for Microsoft's Volume Shadow Copy Service (VSS)
and the Virtual Disk Service (VDS) means snapshots may be taken of iSCSI
targets. These use VSS compatible backup software on the hosts, allowing
application consistent snapshots to be taken without any downtime.
SnapServer DX2 delivered
excellent results in our lab performance tests. Copies of a large video clip to
and from a NAS share over Gigabit returned high read and write rates of
107.5MB/sec, which increased to 109MB/sec over FTP.
Overland claims a top throughput of 350MB/sec for the DX2 and
we found this is quite achievable. Using four Windows Server 2008 R2 hosts,
connected to dedicated iSCSI targets and network ports, we saw the open source
Iometer report a cumulative raw read throughput of over 400MB/sec.
AAlong with top performance, the
SnapServer DX2 looks excellent value,
as all features are included as standard and not as optional extras. Expansion
potential and data protection features are very good and Overland's new
DynamicRAID really does make light work of storage provisioning.