I was working on a little project for a company that was (still) running TS Gateway on a 32 bit x86) version Windows 2008. The reason they did not go for x64 at the time of deployment was that they then used Microsoft Virtual Server as their virtualization platform and had been for some years.
In a number of posts I’ll be discussing some of the steps we took. You are reading the first one.
x86 Windows Server 2008 TS Gateway Migration To x64 Windows Server 2012 RD Gateway
In those early days of W2K8 they had not yet switched to Hyper-V. As an early adopter I was able to show the the reliability of Hyper-V, so later they did.
One of the drawbacks of using Microsoft Virtual Server was that they could not use x64 guest VMs and that’s how they ended up with x86, which was still available for a server OS for W2K8. Since then they have move to Hyper-V and now also run Window Server 2012. Happy customers! So after more than 5 years of service and to make sure they did not keep relying on aging technology it is time to move to Windows Server 2012 RD Gateway and reap the benefits of the latest OS.
Their is no in place upgrade from a x86 to an x64 OS. So this has to be a migration. No worries this is supported. With some insight, creativity and experience you can make this happen. The process reasonably well documented on TechNet, but not perfectly, and your starting point is right here RD Gateway Migration: Migrating the RD Gateway Role Service. These docs are for Windows Server 2008 R2 but still work for Windows Server 2012. Another challenge was we needed to also migrate their custom website used for the employees to check whether their PC is still on and if not wake it up or start it up remotely.
There are some things to take care of and I’ll address these I some later blog posts but I want you to take to heart this message. While an in place upgrade of an 32 bit X86 operating system to X64 version of that OS is not possible that doesn’t mean you’re in a pickle and will have to start over from scratch. For many scenario’s there are migration paths and this is just one example of them, or better two combined,TS Gateway and a Website.
It’s that time of the year again, when TechEd is coming closer. I’m attending the European Edition in Madrid, Spain. But I can guarantee you I will be on line a lot during the USA edition as well. At be attending the USA edition this year if I could but work, time and budget wise I can’t make that happen. This isn’t because the European edition is less, absolutely not. The reason is that at MMS2013 in Las Vegas last month we got the heads up that Microsoft will start talking publicly about the new version of Windows and I’m game for that. Windows Server 2012 is the best Windows version ever but I know what I’d like to see in there to make it even better. I’m kind of curious if anyone at MSFT follows my thinking on this subject. I hope so!
Come and learn amongst your peers, network with them and industry experts. To become competent and gain expertise you are going to have to get out there and expose your ideas, insights and thinking to your peers around the globe. That’s how it works. To those who dismiss quality conferences like this I can only say that you are wrong. To those who claim it’s a paid holiday I can only say that to a liar all other men are liars and to a thief all other men are thieves. Enough said. Invest in knowledge and competence development, it will pay of better than some extra thousands of € in the bank!
So if you can please join me and attend TechEd. It’s a blast and a tremendous learning experience. I never ever miss attending TechEd, not even at times it wasn’t easy for me to do so. You can register here. I hope to see you there!
SMB Direct RoCE Does Not Work Without DCB/PFC. “Yes”, you say, “we know, this is well documented. Thank you.” but before you sign of hear me out.
Recently I plugged to RoCE cards into some test servers and linked them to a couple of 10Gbps switches. I did some quick large file copy testing and to my big surprise RDMA kicked in with stellar performance even before I had installed the DCB feature, let alone configure it. So what’s the deal here. Does it work without DCB? Does the card fail back to iWarp? Highly unlikely. I was expecting it to fall back to plain vanilla 10Gbps and not being used at all but it was. A short shout out to Jose Barreto to discuss this helped clarify this.
DCB/PFC is a requirement RoCE
The more busy the network gets the faster the performance will drop. Now in our test scenario we had two servers for a total of 4 RoCE ports on the network consisting of a beefy 48 port 10Gbps switches. So we didn’t see the negative results of this here.
DCB (Data Center Bridging) and Priority Flow Control are considered a requirement for any kind of RoCE deployment. RDMA with RoCE operates at the Ethernet layer. That means there is no overhead from TCP/IP, which is great for performance. This is the reason you want to use RDMA actually. It also means it’s left on it’s own to deal with Ethernet-level collisions and errors. For that it needs DCB/PFC other wise you’ll run into performance issues due to a ton of retries at the higher network layers.
The reason that iWarp doesn’t require DCB/PCF is that it works at the TCP/IP level also offloaded by using a TCP/IP stack on the NIC instead of the OS. So errors are handled by TCP/IP at a cost: iWarp results in the same benefits as RoCE but it doesn’t scale that well. Not that iWarp performance is lousy, far form! Mind you, for bandwidth management reasons,you’d be better of using DCB or some form of QoS as well.
So no, not configuring DCB on your servers and the switches isn’t an option, but apparently it isn’t blocked either so beware of this. It might appear to be working fine but it’s a bad idea. Also don’t think it defaults back to iWarp mode, it doesn’t, as one card does one thing not both. There is no shortcut. RoCE RDMA does not work error free out of the box so you do have the install the DCB feature and configure it together with the switches.
Last month Carsten (MVP – Virtual Machine) & Kerstin Rachfahl (MVP – Office 365) visited me in my home town. Apart from a short visit to the historic center & a sushi diner amongst friends we also did an interview where we discussed our ongoing Windows Server 2012 Hyper-V activities. We’re trying to leverage as much of the product we can to get the best TCO & ROI and as early adopters we’ve been reaping the benefits form the day the RTM bits were available to us. So far that has been delivering great results. Funny to hear me mention the Fast Track designs as a week later we saw version 3 of those at MMS2013. The most interesting to me about those was the fact that the small & medium sizes focus on Cluster in a Box and Storage Spaces!
While we were having fun talking about the above we also enjoyed some of the most beautiful landmarks of the City of Ghent as a back drop for the interview. It was filmed in a meeting room at AGIV, to whom I provide Infrastructure services with a great team of colleagues. Just click the picture to view the video.