August 2010 I wrote an article on support for Exchange CCR clustering on VMware with iSCSI.

VMware’s response then was very simple and straight forward. Exchange CCR clustering on VMware is not supported on iSCSI!

When asked if VMware had plans to change this support issue in the future the response was promising.

“The Exchange team within VMware requested the vSphere product team to support iSCSI for CCR and DAG clusters. They also would like to remove the RDM requirement for CCR and DAG.
Response from the product team is that they are testing and will update the support stance in a future release.”

Well, the future is now. I stumbled upon a VMware KB article, released May 5, which provides clear guidelines on the vSphere support status when running various Microsoft clustering solutions on VMware vSphere 4.

(more…)

Some time ago.. actually, a long time ago, we here at VMGuru.nl received a sample of a training DVD from TrainSignal. I promised to write a review on it, but I honestly didn’t come around to it due to all sorts of personal stuff. But the DVD box made it safely through the move from one house to the next. So, today I sat down and opened the DVD box.

So, first of all, it’s definitely a proper training. This isn’t your average ‘we demo, you watch’ kind of training. It’s aimed to let you pass the Exchange 2010 exam, but it does more. This 3 DVD box set covers all topics you  need to understand to successfully implement Exchange 2010 into an organization in 40 lessons. It does not only show you how and where to configure things, but most importantly, it tries to show you why. This is the first time I’ve encountered such an approach in a self-paced training package. It really is pretty extensive.

(more…)

I’ve written about Zimbra before. Actually, we here at vmguru.nl use Zimbra for all our email and collaboration. So, today we were invited to join the Zimbra Breakfast Meeting at the Scandic Hotel in Copenhagen.

Zimbra, for the ones who don’t know what it does, is a collaboration suite. It’s the open source exchange alternative. Well, it’s getting more than an alternative. It’s getting competitive in a rapid pace. According to Zimbra, it’s the next-generation Exchange.

A quick overview of the Zimbra features: (more…)

A ‘bit’ of history

Some of you might know me as a dedicated MS Exchange junkie. Ever since Microsoft launched version 5.0 of Exchange, I’ve been working with it and I must admit I never found a collaboration suite quite like it. I’ve had numerous discussions with Lotus Notes or Novell  Groupwise folks but they never conviced me (believe me, I tried all suites hands-on). And yes, I am aware of all the problems Exchange had in the past, including being a spamrelaying nuisance, a memory hog, a disk killer and so on (most errors were caused by faulty configurations, btw).

About 8 years ago some folks in, I think it was Germany, started a project with opensource software to create an Exchange equivalent with nothing but opensource software. Actually, it is pretty logical. If you strip down everything around Exchange, you are left with a (pretty ancient) database system (Jet), a webserver (IIS) and an SMTP engine. So, why can this not be done with MySQL, Apache and Sendmail or Postfix? It should be possible.

(more…)

A few weeks ago I got an assignment to review a colleague’s infrastructure design based on VMware.
The design was fine (because they used my design document as template ) but one thing triggered me.

There was a special port group on one of the virtual switches names ‘MSCLUSTER’. No problem so far but I heard the client recently migrated to iSCSI storage.

The combination Microsoft Clustering Services (MSCS) combined with iSCSI triggered  my alarm bells. As I recalled Microsoft Clustering on iSCSI is not a problem but Microsoft Clustering on VMware with iSCSI is not supported (by VMware).

So, I rejected the design based on this support issue.

This message was not well received, as it turned out they had just migrated their clustered Exchange servers and had been running this way for a while now. Proposing to the client to migrate again was no option. So they tried to  question my findings. They had been running this setup without any problems and Exchange CCR clustering wasn’t real Microsoft Clustering because no disks were clustered, only the Exchange services.

(more…)

This week a colleague called me with a VMware ESX problem. He’s doing a Exchange 2007 implementation and he configured a virtual machine which should function as the Mailbox server. He was complaining that the virtual machine took 13 to 15 minutes just to boot and he suspected a storage issue as they had been struggling with the storage for a few days.

I asked him to check the virtual machine performance tab and asked him if he saw anything strange. Nothing! The server had plenty of memory left and was not using very much CPU.

When I asked him how many resources he assigned to the virtual machine his response alerted me. He configured the virtual machine with 16GB of memory and 4 vCPUs!

When I asked him why he gave the virtual machine so much resources his response indicated that he hadn’t read the Virtual Infrastructure best practices and applied the ‘MS, I might use those resources just once during my lifecycle‘ sizing. When we checked the%CPU ready performance statistics the values were astronomical.

So I explained the behavior of the CPU scheduler to him and asked him to reduce the number of vCPUs to 1 or 2 and try again. When I called him the next day he told me that the virtual machine now booted within a minute.

So bottom line: Give a virtual machine the resources it needs for normal every day operation and be very modest. Monitor the virtual machine and adjust the resource settings according to your findings. In this case, less definitely is more and it’s very easy, especially in vSphere 4, to (hot) add resources. And if you do need 4vCPUs, it can be more effective to deploy two 2vCPU virtual machines instead of one 4 vCPU virtual machine.

As Microsoft Exchange server is one of my area’s of expertise (or so they keep telling me )  I have had numerous discussions in the past whether you should virtualize Exchange or not. For ages Microsoft has claimed it cannot be done, performance would suffer severely, you would not receive support in a virtual environment etcetera.

To be honest, I didn’t really care about it. We’ve designed perfectly working Exchange organizations on VMware when MS was still refusing support. There are some rules you need to respect when you design your messaging environment, but generally it is no problem if you have the required resources available!

(more…)