[Ed. Note: This is the part 2 in Sanjay's vSphere 5 series. Part 1 is here.]
Did you hear the good news for all of you folks implementing thin provisioning with vSphere5? Well it’s good news if you consider good news as being hit by car, as opposed to being run over by a truck and having the driver backup to check what he ran over.
Back in the good old days (are they really old already?) of vSphere4.1, if you thin provisioned your vmdk and your real array ran out of storage, your VM crashed. All of you know that when a server crashes because it’s out of disk space, it’s not a pretty picture. Well in vSphere5 it won’t crash, it just gets suspended. That’s slightly better I guess, but you’re still not running your workload, so while it involves less work for you picking up the pieces, it’s still not a real help.
What you need to do is capacity planning on the real storage behind your thin provisioned vmdks, and that’s where vCenter and other hypervisor-centric management tools reach their limits because they can only see what the vSphere API allows them to see. You need a storage management tool that talks directly to the arrays AND gets data from the hypervisor. This allows you to bridge these two worlds and do capacity planning that accounts for thin provisioning. As an added bonus, if you decide to use thin provisioning functionality that came with your array, a good storage management tool will deal with that, too. A good example of what you might use is SolarWinds Storage Manager, Powered by Profiler, where you can get a view such as the one below. [note if we can’t use the image use the following text for the sentence above. A good example of what you might use is SolarWinds Storage Manager, Powered by Profiler, a product that will give you visibility into both thin provisioning on the array side (for multiple vendors including, EMC, NetApp, Dell, Hitachi and more) and on the vSphere side. Having this visibility also allows you to ensure that you don’t accidentally have both vSphere and your array doing thin provisioning – that really wouldn’t be good.
So in the end, is vSphere5 an improvement, absolutely, but it’s not a panacea, so don’t forget to manage your thin provisioned vmdks and LUNs.
As a side note – if you want to have a deeper technical discussion on IT management topics like this, check out thwack, our community site, with tens of thousands of engineers on it you’re sure to get the answers you need.
Sanjay Castelino is SolarWinds' VP of Product Marketing. He is a long time technologist and a geek at heart. His path to SolarWinds has taken me through hardware design, software engineering, and finally product marketing.