Despite all the talk about new technologies, there’s still a market for SMB/SME capable storage arrays. I already have a QSAN P100V4 in the lab, which is my main iSCSI array and that has been working faultlessly for the last 18 months. Recently reviewed the QSAN Q500-F21, part of the AegisSAN range that supports both iSCSI and Fibre Channel.
The Q500 has five product members as follows:
- Q500-P10 – iSCSI
- Q500-P20 – 10GbE iSCSI
- Q500-F20 – 8Gb Fibre Channel (2-port) & iSCSI
- Q500-F21 – 8Gb Fibre Channel (4-port) & iSCSI
- Q500-F30 – 16Gb Fibre Channel & iSCSI
My evaluation model was the Q500-F21, which provided 4x 8Gb/s Fibre Channel ports and 2x 1GbE. The specification of the array is as follows:
- Dual controller architecture, based on Intel Briarwood SOC (s1200 series), 4GB system memory
- 2U 12-Bay rackmount (2.5 & 3.5″ drive support)
- 6Gb/s SAS, SATA or SSD
- Fully redundant hot-swap modules
- Multi-pathing & Load balancing
- 4x 8Gb/s FC & 2x 1GbE iSCSI per controller
- VAAI support (Hyper-V and Citrix support)
- Thin provisioning support
Full details can be found here – AegisSAN Q500-F21. The hardware itself is unremarkable although practical and follows a pretty much proven form factor, with front mounted drives and rear mounted controllers, fans and power supplies. Drives are mounted in caddies to support either 2.5″ or 3.5″ models. Capacity can be expanded using JBOD SAS expanders and disk shelves (J300Q series).
Software & Features
Modern storage arrays are pretty similar in their hardware design and consequently the major differentiation is to be found in software. For SMBs, this means being easy to use and configure, without lots of specialist storage knowledge. In this respect the F21 performed well. The “Volume Configuration” tab of the web GUI provides an overview of disks installed, RAID groups created from disks, virtual disks (LUNs) and the presentation of those LUNs to hosts. The process of configuring up storage to a host takes a matter of minutes for anyone familiar with basic storage management tasks.
LUNs can be presented as iSCSI or FC devices, but not as both at the same time. Up to 32 iSCSI nodes with 255 LUNs are configurable although the maximum of number of supported LUNs is 2048, however I doubt many configurations would scale to this size.
Standard features include extensive RAID support (0, 1, 0+1, 3, 5, 6, 10, 30, 50, 60 or JBOD & n-way mirrors), global and dedicated hot spares, online volume expansion, write through or write-back cache (battery backup required), caching mirroring and online firmware upgrades
In terms of advanced features, the F21 supports both local snapshots and remote replication, through the QSnap and QReplica features. Thin provisioning is supported with the QThin feature and VAAI virtualisation support is also provided.
With storage arrays of this size, it is easy to create test cases that make performance look good or bad (for example running 100% random writes with heavy I/O queues and large block size) as eventually cache becomes exhausted. Therefore I’ve not included any specific performance figures. However on the testing I performed with random mixed workloads, the F21 performed well and certainly as well as could be expected for the specification. There is a tradeoff using a low power System on Chip designs and QSAN have used iSCSI and Fibre Channel offload engine hardware to boost performance. Arrays like the F21 will never be replacements for high-end storage arrays, however that’s not the market segment they are aimed at.
The Architect’s View
The SMB end of the storage array market is extremely competitive, both from a hardware and software perspective. There are many vendors selling products to the SMB market via the channel including QNAP, Dot Hill, Infortrend and StorTrends. Traditional storage is being attacked by hyper-converged solutions and of course products like VSAN from VMware. However price/performance is a key issue for SMBs. VSAN pricing starts at $2500 per CPU, whereas the Q500-F21 list price is around $6400. So for less than the cost of licensing VSAN on a group of single CPU servers, IT teams could have dedicated storage hardware.
The AegisSAN is a solid performer and as a long-term QSAN array user I can confirm reliability of their hardware. As I wrote recently, there’s still value in dedicated storage arrays, but the rise of Cloud and of software defined storage means vendors like QSAN will need to innovate and continue to pack in features, just to stay in the game.
Comments are always welcome; please indicate if you work for a vendor as it’s only fair. If you have any related links of interest, please feel free to add them as a comment for consideration. QSAN provided a Q500-F21 array for evaluation which has subsequently been returned to the vendor. No vendor approval or review is provided prior to posting.
Subscribe to the newsletter! – simply follow this link and enter your basic details (email addresses not shared with any other site).
Copyright (c) 2009-2014 – Chris M Evans, first published on http://blog.architecting.it, do not reproduce without permission.