Category: virtualization

Exchange 2007… Better late than never

 

Count me in as one of the many Administrators that finally got around to moving from Exchange 2003 to Exchange 2007.   Yes, it’s almost 2010, and probably just a few months away from the release of Exchange 2010.  I never disagreed with Microsoft’s decision to release Exchange 2007 as a 64 bit only application.  It’s just that it made it incredibly difficult to find a way to transition when your infrastructure is full of physical 32 bit servers.  I was constantly reminded that my Exchange 2003 server was brittle, a resource hog, and lacked many of the abilities that the end users and applications were demanding.  Twenty-five minute reboots, and inexplicable behaviors did not instill confidence.    It was time to make the move.

My timing couldn’t have been better.  I have a new virtualized infrastructure powered by some Dell blades, running VMWare ESX 3.5 using a Dell/ Equallogic PS5000 SAN to help with this transition.  It didn’t take away from the normal shrewd planning necessary on a project of this nature.  It just made it easier.  The other benefit to deploying 3 year old software is that issues, workarounds, and fixes to Exchange, as well as how to make it play nicely with other components (ISA, CRM, etc.) were well documented. 

With respect to running Exchange 2007 in a virtual environment, I noticed information on sizing is difficult to find.  Capacity planning guidelines still reflected deployments with physical servers (read: more is better), and white papers on virtualizing Exchange appeared to have the intended audience of large enterprise environments only.  My environment is relatively small, and a single server was going to be handling all Exchange roles.  Based on my environment of about 50 users and 100 mailboxes, I sifted through all the material I could find, threw in a few wild guesses, and decided with the following configuration.

  • 1 vCPU
  • 2.5GB of RAM
  • Primary OS resides in VMFS volume on the SAN
  • Using guest OS based iSCSI initiator with MPIO enabled, dedicated NTFS volume for Exchange database. 
  • Using guest OS based iSCSI initiator with MPIO enabled, dedicated NTFS volume for Exchange transaction logs.  

The transition occurred over one weekend, while the remainder of the outstanding issues were cleaned up throughout the week.  A moment of embarrassment occurred when I realized my thorough planning never took into consideration that the “move mailbox” function would hit the transaction logs so much.   I didn’t see it until it was too late.  The partition for the transaction logs filled up and the services shut down.  But, thanks to the ease of handling storage with the SAN, I was able to create a new LUN, initialize it in the OS, and change a couple of drive letters.  Ran a backup to commit the transaction logs to the database, and I was back in business.  The only puzzle that took me far too long to figure out was getting the AutoDiscover function in Exchange 2007 to work as intended.  It is worthy of it’s own post at another time.

As far as performance goes, I couldn’t be happier with it running as a VM.  I truly didn’t know how it would react under the settings I established, and was ready to make whatever changes necessary, but it has been performing very well.  Below are some very simple utilization numbers to give you an idea.

CPU:  Hovers around 50% utilization during the day, and around 15% utilization during off hours.  CPU Ready values range anywhere from 20 to 200 milliseconds.  This VM has just 1 vCPU assigned to it.  I wanted to keep it this way if possible, so that it could use the “Fault Tolerant” feature of vSphere when we upgrade.  Looks like I get my wish.

RAM:  Typically runs about 50% of the 2.5GB assigned.  No higher than 75% utilization during the busiest time of the day, and 15% utilization during off hours

Network:  Runs about 1.2 MBps.  Spikes of 40 MBps occur only because of some on-host backups occasionally occurring.  Bandwidth utilization is imperceptible during off hours.

Disk I/O:  Hard to gauge, but mostly because the need seems to be so low.  The OS partition coming from the VMFS volume might show 200KBps, but has bounced up to 7MBps on occasion.  No performance data yet on the drives connected via the guest iSCSI initiator.  I think they qualify as “fast” until I find anything that suggests otherwise.

Perception:  You won’t find this on any ESX or OS performance monitor.  But it’s importance cannot be underestimated.  I had about half of the staff comment about how much snappier their Outlook clients and OWA was working for them.  I never have staff stop by and offer random comments telling me how fast something is.  It’s a nice compliment to the improvements of Exchange 2007, and what it is running on.

No more painfully long restart times for me now.  It’s one of the more overlooked benefits I’ve noticed while moving my systems over to my new infrastructure.  Planned server restarts are a part of responsible management of IT systems.  Anything that can be done to reduce any interruption is appreciated.  A two minute restart is always welcome

It probably goes without saying that I took great joy decommissioning the old server.  Hopefully this will be me in a good position when Exchange 2010 comes off the presses.

Virtualization. Making it happen

 

It’s difficult to put into words how exciting, and how overwhelming the idea of moving to a virtualized infrastructure was for me.  In 12 months, I went from investigating solutions, to presenting our options to our senior management, onto the procurement process, followed by the design and implementation of the systems.  And finally, making the transition of our physical machines to a virtualized environment.

It has been an incredible amount of work, but equally as satisfying.  The pressure to produce results was even bigger than the investment itself.  With this particular project, I’ve taken away a few lessons I learned along the way, some of which had nothing to do with virtualization.  Rather than providing endless technical details on this post, I thought I’d share what I learned that has nothing to do with vswitches or CPU Utilization.

1.  The sell.  I never would have been able to achieve what I achieved without the  support of our Management Team.  I’m an IT guy, and do not have a gift of crafty PowerPoint slides, and fluid presentation skills.  But there was one slide that hit it out of the park for me.   It showed how much this crazy idea was going to cost, but more importantly, how it compared against what we were going to spend anyway under a traditional environment.  We had delayed server refreshing for a few years, and it was catching up to us.  Without even factoring in the projected growth of the company, the two lines intersected in less than one year.  I’m sure the dozen other slides helped support my proposal, but this one offered the clarity needed to get approval.

2.  Let go.  I tend to be self-reliant  and made a habit of leaning on my own skills to get things done.  At a smaller company, you get used to that.  Time simply didn’t allow for that approach to be taken on this project.  I needed help, and fast.  I felt very fortunate to establish a great working relationship with Mosaic Technologies.  They provided resources to me that gave me the knowledge I needed to make good purchasing decisions, then assisted with the high level design.  I had access to a few of the most knowledgeable folks in the industry to help me move forward on the project, minimizing the floundering on my part.  They also helped me with sorting out what could be done, versus real-world recommendations on deployment practices.  It didn’t excuse me from the learning that needed to occur, and making it happen, but rather, helped speed up the process, and apply a virtualization solution to our environment correctly.  There is no way I would have been able to do it in the time frame required without them.

3.  Ditch the notebook.  Consider the way you assemble what you’re learning.  I’ve never needed to gather as much information on a project as this.  I hated not knowing what I didn’t know. (take that Yogi Berra)  I was pouring through books, white papers, and blogs to give myself a crash course on a number of different subjects – all at the same time because they needed to work together.  Because of the enormity of the project, I decided from the outset that I needed to try something different.  This was the first project where I abandoned scratchpads and binders, highlighters (mostly) and printouts.  I documented ALL of my information in Microsoft OneNote.  This was a huge success, which I will describe more in another post.

4.  Tune into RSS feeds.  Virtualization was a great example of a topic that many smart people dedicate their entire focus towards, then are kind enough to post this information on their blogs.  Having feeds come right to your browser is the most efficient way to keep up on the content.  Every day I’d see my listing of feeds for a few dozen or so VMware related blogs I was keeping track of.  It was uncanny how timely, and how applicable some of the information posted was.  Not every bit of information could be unconditionally trusted, but hey, it’s the Internet.

5.  Understand the architecture.  Looking back, I spent an inordinate amount of time in the design phase.  Much of this was trying to fully understand what was being recommended to me by my resources at Mosaic, as well as other material, and how that compared to other environments.  At times, grass grew faster than I was moving on the project at the time, (exacerbated by other projects getting in the way) but I don’t regret my stubbornness to understand what was I was trying to absorb before moving forward.  We now have a scalable, robust system that helps avoid some of the common mistakes I see occur on user forums.

6.  Don’t be a renegade.  Learn from those who really know what they are doing, and choose proven technologies, while recognizing trends in the fast-moving virtualization industry.  For me there was a higher up front cost to this approach, but time didn’t allow for any experimentation.  It helped me settle on VMware ESX powered by Dell blades, running on a Dell/EqualLogic iSCSI SAN.  That is not a suggestion that a different, or lesser configuration will not work, but for me, it helped expedite my deployment.

7.  Just because you are a small shop, doesn’t mean you don’t have to think big.  Much of my design considerations surrounded planning for the future.  How the system could scale and change, and how to minimize the headaches with those changes.  I wanted my VLAN’s arranged logically, and address boundaries configured in a way that would make sense for growth.  For a company of about 50 employees/120 systems, I never had to deal with this very much.  Thanks to another good friend of mine whom I’d been corresponding with on a project a few months prior, I was able to get things started on the right foot.  I’ll tell you more about this in a later post.

The results of the project have exceeded my expectations.  It’s working even better than I anticipated, and has already proven it’s value when I had a hardware failure occur.  We’ve migrated over 20 of our production systems to the new environment, and will have about 20 more up online within about 6 months.  There is a tremendous amount of work yet to be completed, but the benefits are paying for themselves already.