Thursday, August 28, 2008

New Formula: Exchange + Virtualization = Microsoft Support

Yes, the new formula is correct. And I did not expect to see this so soon. Microsoft has announced that you can run Exchange 2003/2007 in a Virtual Server 2005 R2/Hyper-V virtualized environment and get Microsoft Professional Support Services. Here is the official Microsoft release about this. There are a details for each configuration (e.g. all 2007 roles supported except Unified Messaging), but this is a step in the right direction.

Also, Windows ITPro's article on this mentions that Microsoft has created a Server Virtualization Validation Program (SVVP) and that VMware is in the process of attempting to achieve certification. This is not a show stopper in my eyes since VMware supports clients Windows & Exchange hosts currently.


Saturday, August 23, 2008

First Experiences with VMware 3i

Overall, I love it. I'm might start drinking the VMware 3i koolaid. And if you're familiar with VMware Server, this will be an easy transition. Or if you are new, you'll need to hover over icons until you remember what they are. This is pretty easy though. If you don't know, 3i is now free. 3i is a slimmed down version of 3.5 which cuts multiple host type features (e.g. VMotion, Update Manager, etc).

So, I finally had some time today, and after reading all the documentation that came with my new server (Dell PowerEdge 2900 III) and inspecting the inside & removing the USB flash drive (Kingston 1GB) I fired it up. And yes, I normally read all documentation before I start to use a product. And boy, do I like the purr of a dual quad core, six 15k hard drive, & dual power supply server. After about 30 minutes, I actually turned off the music since it was bothering me and listened to the humming of the server.

Some notes on the 3i setup on my Dell. I quickly ran through the BIOS configuration and realized even though I had (read: paid / I don't have enough time in my life with my new daughter) Dell to pre-load 3i on this server, they did not enable the internal USB port to allow VMware 3i booting and on the CPU instructions, VT was disabled. If you recall from my previous blog posting, Intel's VT or AMD-V is a requirement. Nice touch Dell. After that, I booted it up, and 3i just loaded. I changed the root password and set the DHCP IP to static and then used another PC's web browser to download the VMware Infrastructure Client (aka VI Client) which is used to manage your ESx host. The only aspect of 3i I had to configure was storage. So, I gave all 6 hard drives in a RAID 10 configuration to VMware (file system is called VMFS, and I set the block size to 1MB, since I don't expect to have a single file over 256GB) to 3i. So, it handled the formating and everything. So, I now had 836GB of space.

After that, my first OS to install on my new VMware server was Windows 2008 Standard 64 bit. You run through adding a new virtual machine, and I select a CPU, 1GB of ram, and 20GB of hard drive space and place the install CD on your local PC and then select "Connect DVD" and your local DVD/CD automatically appears on the "server vm". I was running this via a 10/100 network, and the install proceeded very quickly compared to Windows 2003. Keep in mind, I had never installed 2008 before. It went very smoothly the install. No issues on install or setup. But, little did I know, the new server OS takes over 10.5GB of space. Holy smokes. I guess I'll be re-installing Windows 2008 again. Oh well.

The management console shows quite a number of performance related statistics (e.g. overall memory usage, network, hard drive, etc) for all virtual machines. Like I initially said, anyone with any VMware Workstation/Server experience will feel right at home, otherwise it's still fairly easy to get around. I'll post again once I dig deeper in the product.


P.S. Comments or feedback is always welcome.

Monday, August 18, 2008

Virtualization Performance is better than you think for Exchange Server

Hello Everyone,

The common thought is Exchange Server does not get virtualized. But, I'll tell you what, Exchange should be virtualized. Applications that are mission critical should be protected using a number of backup, high availability, and fail-over type solutions. I consider virtualization a method of fail-over.

The biggest concern I frequently hear about Exchange is performance (after complexity - I would disagree on that one). Well, the performance difference between virtual and physical environments (at least VMware ESx, haven't seen performance benchmarks of Hyper-V) is a lot closer than one would expect when properly configured (I don't want to hear about the single SATA hard drive configuration you are running with 1GB of ram). I'll summarize the technical details of a performance test of Exchange 2003, VMware ESx 3.0 on fibre channel on Dell/EMC hardware (all 32 bit, 2GB of memory only). URL for the report is here in PDF.

Close Ball-Game
1) a single virtual CPU could obtain 76% performance of a physical CPU (clocked at 1300 heavy user profiles with acceptable performance using LoadSim, Microsoft's Outlook/Exchange testing tool)
2) 2 virtual CPUs could obtain 71% performance of a 2 physical CPU solution (support for up to 2200 heavy user profiles)
3) CPU Utilization - 30% difference in utilization, but not an issue. Exchange is not a heavy CPU user. More important to focus on I/O and memory.
4) VMware's memory sharing technology did not show any performance degradation.

One of the biggest surprises for me was the VMware memory sharing technology had no effect. I'll be taking a closer look at this in other benchmarks and personal testing since it's hard to believe that there was no difference. Just to re-cap the memory sharing technology, if you run 4 virtual machines (aka vm) with Windows 2003 Server, you're running many of the same services (e.g. netlogon.exe, explorer.exe, etc) which consume the same memory, so VMware does a "single instance" type memory sharing between all 4 vm's.

To summarize, if you have the I/O capabilities and want to improve your business continuity solutions, I would consider looking into this further. I wouldn't just count this out. And I plan to run my Exchange Server in ESx very soon. Hope to see you there...


Monday, August 11, 2008

Serious DNS Vulnerability (Kaminsky) Can Affect Email Services

Hello All,

This is the beginning of shorter posts, but more often.

This recently released serious DNS vulnerability (found by Kaminsky) can affect email services, so while hackers are spoofing DNS for web site attacks, the same could be done for email attacks. See the US-Cert for an overview of the issue. This effects dozens of DNS implementations including Windows DNS.

Official US-Cert Posting on the DNS Vulnerability

An Illustrated Guide to the Problem

There is some discussions about what the best approach is to fix it (e.g. DNSSEC, increase Query ID, randomize the source port, IPv6, SSL, etc). So, it at the moment, the easiest fix is increase the query ID and randomize the source port. For your servers, use (at least for Windows Server DNS), the root based hints included in the operating system. "Man in the middle" attacks are a lot more common and dangerous than people realize, hence why I prefer using my EVDO card than some random WiFi hotspot. Stay safe.