Live Migration Test

So this is out of order as I have a lot of posts to write to get caught up to the current state of our prodution environment .... but I thought it worth sharing since I'm just staring at a progress bar anyway.

In true gung ho form ... I'm testing live migration on a non-backed up production server.  I'm moving a backup domain controller from the original server to the new server (which has been attached to our storage array and preped for clustering). 

The test?  I've got a ping running to the server.  Funny thing?  As I was writing that my VPN connection dropped ...  Oh yeah ... That was the VPN host.  Oops...  well it popped back up 15 seconds later.  The ping test had a few dropped packets and a few more destination host unreachables then picked right back up.  I estimate about 15-20 total pause time for the server but it's a pretty inaccurate test.  Aside from that it worked pretty well.

Why Hyper-V

There are some diehard Anti-Microsofters out there who ask this question by default without really caring what the answer is, and this post is not for them.

The truth is I was very skeptical about Hyper-V and the decision to try it out was made somewhat arbitrarily without peer input simply because I wanted to understand it better before actually implementing a VMware (I have several years of multi ESX server environment experience) production environment.

Most of the information I had been reading was somewhat dated and referred to Hyper-V 2008.  Hyper-V 2008 R2 is all kinds of improved, live migration being one of the biggest new features offering direct competition to VMware’s Live Motion.  In fact, we've been running Hyper-V in our production environment for just 10 days shy of a year now, and I'm still often wading through dated forum posts and references when looking up new information.

So back to the point;  I picked Hyper-V for our initial environment because I wanted to learn it, be sure it was in fact not a feasible solution for us, and was fairly confident it would be easy to migrate any small implementation we crafted to a vSphere environment later on.

I budgeted $17,000 for VMware software licensing in 2011 just to be safe, and was surprised (granted only slightly as my boss is pretty awesome) that the amount was approved.  I have not yet altered the 2011 budget, but I was able to acquire almost all the necessary, equivalent Microsoft System Center and Server 2008 R2 Datacenter edition licensing within the remainder of 2010's budget (the total project amount of which was barely more than the $17K).  

What I’m implying there is that the Hyper-V solution - and I’m talking the beefed up full SCVMM (System Center Virtual Machine Manager) with full Server Datacenter Edition licensing on four processors of the first two of three planned core host servers - is still pretty inexpensive compared to VMware’s equivalent licensing.  Now we’re not exactly comparing apples to apples here because of the class of licensing, but that’s also part of the point; for library systems in Wisconsin, Microsoft’s Open Academic or Academic Select licensing tiers are tough to beat.  VMware’s special licensing pricing was better than for a random small private company, but nowhere close to Microsoft academic licensing.  Time allowing, I’ll go back and study the standard Microsoft licensing pricing vs. VMware standard licensing pricing to see how that compares, but for now, it is not relevant.  Also I’ll compare the totally free versions (features and functionality) of both.  Well … more likely I’ll link to someone else’s research and comment on it like I know what I’m talking about.

Sure there are some features in ESX\ESXi that I miss.  Memory over-subscription\commitment was a big one.  But with the servers we have, and are provisioning, that’s not planned to be an issue for quite some time.  Also, SP1 for Server 2008 R2 is scheduled to have “Dynamic Memory” which is Microsoft’s answer to memory limits on server consolidation.  It’s not a perfect solution as guest OSes need to support hot swapping memory (Windows 2003 SP2 and greater support this, and though MS is not providing support up front, I’m sure either they or someone will make it work with various flavors of Linux guests in the future as well.  It is however a safer solution than straight over subscription\over commitment. 

All in all, Hyper-V is pretty slick, especially for a Microsoft shop.  Why MS only?  TCO – but that’s another post in another blog.

Since I'm so awesome ...

I was asked recently (4 months ago) by a peer group to publish a bunch of general IT info relating to virtualization and thought, why not make a blog of it... it's not like I have much else to do...

In this Rockstar Virtualization blog I'll lay out the virtualization roadmap we're implementing at WVLS, and explain how we got to where we are and eventually, once I catch up, will blog about the progress we're making.  You'll find out why we chose Hyper-V, how we came about securing the licensing, what equipment we use and why, and how we're using what we've built.

I'm looking forward to it ... laters!