Blog Posts

I just posted a new video to delltechcenter.com on the virtualization demos page. It is a demo of how Microsoft System Center Virtual Machine Manger 2008 (SCVMM), which is currently in beta, can be used to clone a Hyper-V virtual machine. This was fun to put together because this is the first chance I've had to work with SCVMM 2008.

There were a couple of surprising things that I discovered around the cloning demo. The first was that a VM must be prepared in advance by running sysprep (at least for windows VMs) before doing the clone. With VMware Virtual Center it is possible to have the sysprep and other customization done as part of the clone. The second surprise to me was that Windows Server 2008 includes sysprep. In the Windows\system32\sysprep directory it is there waiting to be run. And when it is run there are only a couple of very simple options to pick from. I think that it is a much easier tool to use this way. With previous versions of Windows Server the sysprep tools were on the installation cd in a deploy.cab file, which meant you had to track down the cd. I like it better just included with the OS install - although I wonder if this is a potential problem.

In addition to the Hyper-V clone demo, Scott also put up a cool demo of SCVMM managing some VMware ESX Servers and VMs. So you might want to check them both out while you are there. We're going to talk about these demos in today's chat on Hyper-V Management.

Todd

Virtual Geek has a some great performance and power consumption numbers up on his blog for virtualizing Microsoft Sharepoint. I've gotten lots of questions over the past year or so about how SharePoint would perform in a VM and this is the best data that I have seen to answer those questions. He has info about how you can download the full report from EMC's Powerlink site, but the charts and info in his blog post seem to cover the main points. The amount of savings in terms of power are so big as to be unbelievable, but after looking at the details behind them it all seems to add up. An excellent read - I recommend that you check it out.

Todd

During the weekly DellTechCenter Tech Tuesday chat a couple of weeks ago a question came up about performance monitoring with the PowerVault MD3000i iSCSI array. The initial question was how to do performance monitoring from Linux and we addressed it in a followup discussion thread. The answer at this point was to use iostat for Linux or perfmon in windows to monitor performance on each host that was attached to the MD3000i array. This lead to a follow on question which was how to monitor the performance for the entire array.

The management tool for the MD3000i, PowerVault Modular Disk Storage Manager, does not include any performance stats beyond basic iSCSI port level stats. Some investigation into the command line interface for the MD3000i revealed that there is a command to capture the performance stats on the array. Using the smcli, which is installed as part of the MDSM, it is possible to collect the performance stats for the array, controllers, and virtual disks to a csv file.

This turns out to be pretty cool and not too hard to do. Just a simple command and a little bit of spreadsheet magic and you too can produce cool performance graphs of your MD3000i. The details are posted here on delltechcenter.com.

Todd

In the past I was somewhat biased towards 2-socket servers for virtualization - which was due to the results of some testing we did. I had of course realized over the past year or so that things had changed and the 4-socket servers were now more competitive. So when I ran the series of chats on Selecting a Server for Virtualization, I decided that it was a good opportunity to re-run some of those exact same tests with the brand new R900 that had arrived in the lab. I posted the results on a TechCenter page so you can see the full results, but the short summary is that the R900 stacks up as more efficient than the 2950 we tested in the previous paper. The R900 showed 10 to 23 percent better performance per watt than the older 2950. The question that remains is how would the R900 compare to a current generation 2950?

Todd

Our upcoming chat today on benefits of iSCSI and Virtualization led me to some quick research to see what I could find. The first hit was for a Dell Whitepaper on why iSCSI is the best storage for virtualization. Turns out this is a whitepaper that I reviewed internally before it was published about a year ago.

I was a long time fibre channel user and thought that some of the points in the paper were a bit harsh. The funny thing is that reading it now I agree with it much more. The paper didn't change, but my experience in the last year with iSCSI has changed me. I really do think that iSCSI is easier and the performance concerns that I had, for the most part, don't concern me anymore. Although I must admit that I still like my CX3-80 fibre channel storage.

Todd