Virsto, how do I back it up?

The moment anyone inside EMC or VMware buys anything, ever, the first question I get from an end user or a sales person is ‘How do I back it up?’

VMware acquires Virsto on Monday evening and starting at 7:00AM on Tuesday morning I’ve been getting ‘How do we back up Virsto?’ questions.

Fair question but it plays to not understanding what Virsto.

When you look at Virsto for vSphere (There is a Hyper-V flavour where you run in the parent partition but regardless of how they’re implemented it’s turtles all the way down) you see serialisation of write I/O at a *physical* host level through the use of logging, the contents of those logs being asynchronously written to a shared pool of physical LUNs (Usually carved from an external storage array) probably abstracted away with a distributed file system presented to all physical hosts.

It’s most definitely more complicated than that as I only had the elevator pitch in a crowded corridor as I was off to find some ice cream in San Francisco but think of it this way, you’re running some of the stuff you find in the storage array controller today across your physical hosts.¹

When you understand at what level Virsto operates at it becomes clear you backup and restore your virtual machines the same way you always did. Using VADP with CBT & CBR or Guest level backup and recovery with products like VDP/VDP Advanced, Avamar, EMC NetWorker or other.

When it comes to backup and recovery the best thing VMware did was shoot VCB in the head, the worst thing they could probably do would be to break the VADP workflow entirely. Virsto does not break the existing workflow.

What could change is the longer term is additional usefulness of the snapshots taken during VADP operations. Lets face it VMFS snapshots are incredibly horrifying for a whole number of reasons not worth repeating here but Virsto can solve many VMFS snapshot limitations.

Whack in some VFCache cards to keep those Virsto physical host logs closer to the CPU and with random reads you have yourself a real party when it comes to test & dev snapshots, but I haven’t looked at that at all as it was a thought that occurred to me at the time so I’m certain your mileage will vary.

Bottom line, regardless of VMware now having their own storage controller layer for their software suite your backup and recovery workflow does not change. 

¹‘So VMware is competing against storage array vendors now?’ No I don’t think so, at least not any more than they already were. if you consider Virsto to be a write serialization technology it’ll improve the overall random write performance of any external storage array providing the underlying storage. In that sense it makes array vendors offerings more valuable since hosts can get more work done in the same amount of time as they could before.

On the other hand if your entire value prop is wrapped up in the fact that VMFS snapshots suck donkey ass and your array snapshots do not then this will be a net negative for you going forward.