Qsan AegisSAN Q500-P20-D316 review

Qsan claims its AegisSAN Q500-P20 IP SAN appliances are the first to be built on Intel’s “Briarwood” Atom platform – low-power SOCs designed specifically for storage applications. The D316 reviewed here features two Atom-based RAID controllers, running in active/active mode – so if one fails, all operations move to the other.

Qsan AegisSAN Q500-P20-D316 review: specifications and setup

Each controller offers two 10GbE and two Gigabit ports for data, plus one Gigabit management port. There are 16 bays for internal hot-swap SAS drives, and each controller offers an external SAS connector, too, supporting 256 hard disks (you can daisy-chain Qsan’s J300Q JBOD disk shelves, which also have dual-redundant PSUs and fans). If you want to use SATA drives you can use Qsan’s MUX interposer boards, but this rather negates the cost benefit of using cheaper drives. The whole unit is powered by dual-hotplug 550W power supplies, with swappable fan modules.

When setting up the appliance, use either web browser or Qsan’s QCentral utility, which is designed to manage multiple appliances from a single interface. Your first job is to create RAID Groups (RGs), which can comprise any or all available hard disks. Both interfaces provide wizards that will grab all the drives and offer to create the most appropriate array from them. Array options include stripes, mirrors, RAID5 and 6 and Qsan’s N-way mirroring, where the array can contain multiple mirrors for N-1 failover.

Thin provisioning is supported via Qsan’s QThin feature, which is applied only to RGs. Policies can be set for thinly provisioned volumes to provide alerts when space is getting tight. You can set up to six capacity thresholds, and actions include sending an email, reclaiming space, deleting snapshots or taking the RG offline.

For iSCSI targets, you create virtual disks (VDs) within an RG, where you decide on a size and set parameters such as the block size. If you run low on space, more disks can be added to the RG and VDs expanded into them. Each VD is assigned a LUN, and during attachment you can decide which host initiators may access it. For global access just use a wild card; you can also set the LUN to read only or read/write.

Snapshots can be run manually or at scheduled 15-minute, hourly, daily, weekly and monthly intervals on selected VDs. All snapshots for each VD can be viewed from either QCentral or the web interface, where you can expose them as read-only or read-write targets for selected hosts. Snapshot rollback is a simple process. After taking the primary VD offline, you select this option from the snapshot’s dropdown menu and it will restore the VD for you.

Qsan AegisSAN Q500-P20-D316 review: replication, cloning and performance

Replication over the LAN or WAN is an advanced option available with Qsan’s QReplica licence. It requires the last Ethernet port on each appliance to be dedicated to this task – which, in the case of the Q500, is the second Gigabit port. Cloning, however, is a standard feature, which can be used for simple VD backup or to create a replica – possibly for testing and development. You first create a VD that’s the same size as the source and select the Backup option. After associating the source with the backup VD, manual cloning can be run and released so you have a duplicate. You can also apply a schedule for it to run a full copy and update it regularly using snapshots.

To test 10GbE performance, we loaded the Q500-P20-D316 with four 4TB WD Enterprise SAS2 hard disks, then used an HP ProLiant DL580 Gen8 with quad 2.8GHz E7-4890 v2 Xeons, 256GB of DDR3, a dual-port Intel 10GbE card and Windows Server 2012 R2. From our RAID5 array we created a 1TB VD and assigned it to the server over a 10GbE fibre link. With jumbo frames and a 50GB test file, Iometer reported raw read and write speeds for 64KB sequential transfers of 1,080MB/sec and 806MB/sec, equivalent to 8.4Gbits/sec and 6.3Gbits/sec. To test maximum IOPS, the Iometer block size was changed to 4KB and saw a good reading of 75,000 IOPS.

Qsan AegisSAN Q500-P20-D316 review: verdict

The Q500-P20-D316 isn’t as fast as Qsan’s Xeon equipped AegisSAN LX P600Q-D316, but it provides the same high levels of redundancy and expansion potential. It represents top value, offering plenty of network storage features for a competitive price.