Dell EqualLogic PS6510X review

For replication, snapshots of selected volumes are stored in other groups called replication partners. During setup you can choose one-way replication to another group, bi-directional replication between groups or designate one group as a central location to which multiple groups can be replicated. If a volume gets lost or damaged you just clone a copy of the replicated volume and promote it as a new volume.

Dell’s optional SAN HeadQuarters is designed to manage multiple appliances from a central console and also sees a redesign to allow it to support the new features. You add your groups which all appear in the left pane along with a choice selection of statistics and graphs for each one.

You can view detailed reports on capacity which show the total space for the group and how it’s split up into volumes and snapshots. The display has been updated with graphs showing total group storage and I/O capacity along with headroom for both categories.

The network option has a speedometer dial showing overall network utilisation although we noticed that Dell appears to have its calculations wrong. It’s using a maximum available throughput of 20Gb/sec, which incorrectly showed a 50 per cent utilisation during our maximum throughput tests. Only 10Gb/sec bandwidth is available due to load balancing so utilisation should be close to 100 per cent.

For testing we used a Dell m1000e blade server equipped with M610 blades with dual L5530 Xeons, 16GB of DDR3 memory, dual port 10GbE mezzanine cards and running Windows Server 2008 R2. We used a PowerConnect 8024 10GbE switch blade and all ports on the PS6510X were linked into it.

We tested with MPIO links configured for both 10GbE ports on the M610 blade. Setting these up using Dell’s host integration tools is swift as you just connect the physical network ports, log on to the portal and target and Dell does the rest. Note that jumbo frames must be enabled throughout along with flow control and all iSCSI initiators must have the least queue depth load balancing option selected.

Using one M610 blade, we logged on to four 100MB virtual volumes and ran Iometer configured with one disk worker for each volume and 256KB sequential read transfer requests. It reported a steady raw read throughput of 1158MB/sec, which equates to 9.05Gb/sec – close to wire speed for a 10GbE link.

We then brought a second M610 blade server into play and logged it into it own dedicated quartet of virtual volumes. With Iometer running on both server blades we saw speeds of 622MB/sec and 537MB/sec respectively also equating to a cumulative throughput of 9.05Gb/sec.

Our test results show that the PS6510X is quite capable of delivering top performance over 10GbE networks. Combine this with its high capacity and expansion potential plus the fact that one price includes virtually all features as standard and you have the perfect IP SAN appliance.