A couple of weeks ago the Dell FX2 disk controller was added to the Virtual SAN Compatibility Guide and shortly after the Ready Node configurations were added. For those who haven’t looked at the Dell FX2 platform, it is (in my opinion) hyper-converged on steroids. Not only can it provide you with 4 compute nodes in 2U it also packs a 10GbE switch and can hold two storage blades with each 16 disks in it. What? Yes indeed, that is a lot of horse power in a single system.
I am working with a customer right now who is designing a new cluster configuration leveraging the Dell FX2 platform. In this case they are planning on 16 hosts in total. In their case after assessing their current workloads they are going with the FC430 E5-2670 v3 series with 12 cores (dual processor). Each host will have 256GB of memory and uses SD to boot from.
From a storage perspective they are looking to use the FD332 storage blades. Two per FX2 chassis, fully maxed out with 32 drives in total, which is 8 drives per host. All-flash by the way, leveraging 1.6TB devices for the capacity tier and 400GB devices for the write cache. Yes that is 38.4TB raw capacity per FX2 chassis, times 4… ~153TB.Not a coincidence that the configuration is very similar to the “AF-6 Series – Dell FX2 Platform”, they prefer to use a certified and tested solution instead of picking their own components, which makes sense if you ask me.
One of the key reasons for them to go with all-flash is the beta which is coming up. They want to get their hands dirty with functionality like deduplication, checksumming and RAID-5/6 (aka erasure coding) as soon as possible. All 4 chassis will run in one site first for testing purposes for now and they are considering after the initial tests to deploy them across two sites in a stretched configuration. They asked me what the big benefit was of RAID-5 or RAID-6 over the network (aka erasure coding) and it definitely is the lower raw capacity requirements it will lead to. If you look at the current FTT=1 implementation it means that a 20GB disk requires an additional 20GB for availability reasons, which means 40GB in total. With an RAID-5 implementation instead of RAID-1 this 20GB disk would only require 26.6GB of disk space, that is a savings of almost 14GB immediately. And that is before any type of space efficiency (dedupe) is enabled. Anyway, back to the FX2.
So far only “all-flash” has made it to VSAN Ready Node list, and of course components are also listed as in the disk controller “FD332-PERC” (single and dual ROC) and I’ve seen the 1.8″ flash devices also on the list. Waiting to see what one of these boxes would cost in an all-flash configuration, and hoping to also see a hybrid configuration soon. I’m a fan of the Dell FX2 systems, that is for sure.