Usability - Productivity - Business - The web - Singapore & Twins

Comparing Microsoft and IBM deployment diagrams - Part 1

Depending on whom you listen to TCO is the lowest for [insert-your-product-of-passion-here] Robert Sutton (a must read, yes - every book ) suggest to base management decisions on solid evidence . So what is part of TCO? Hardware and software prices, real estate in the server room, electricity and cooling, labour for the admin for regular operations, patches and upgrade as well as opportunity cost for downtime. I'd like to shed some light on the hardware side. In a loose series will compare the hardware deployment for various IBM and Microsoft scenarios. For starters I use a comparison of plain Domino with plain Exchange. In a later post I will add mobility, instant messaging, collaboration and whatever comes to my mind. My first scenario is a single location with 12000 heavy mail users who demand high availability. Since I'm not a Microsoft expert I need to poke into public available resources for the deployment diagram and I guess I'll stand corrected in one or the other case. The first thing I had to learn about Exchange is that an Exchange server can have different server roles and that it is considered best practice to split these in large installations. HP's sizing tool for Exchange 2007 was used for the Exchange estimates.The tool suggest 12 HP servers with 20 TB of storage. Since High Availability (HA) in case of Exchange means an active-passive setup, you buy 6 servers that don't do anything as long as the other 6 don't fail (HP builds great machines, so the probability is rather low). The 12 servers do not include the setup for Microsoft Active Directory which would add at least 2 more boxes (one could argue the directory is needed in any case - which I happily would debate, but that's a topic for another day). The whole setup looks like this:
Exchange Deployment for 12000 users
Now let us compare this to a Domino setup on an IBM System P. On a System p550 (that's not even the latest IBM P7 system) you would choose to run 3 LPAR (Logical partitions) with a total of 5 Domino partitions (4 for user access, 1 for directory and hub). Since Domino is an active-active cluster you have 6000 users per server or 1500 users per Domino partition (which is calculated on the super-save side. I've seen production systems with 10k and more users on one partition - but we have heavy users here). The whole setup looks like:
Domino cluster for 12000 users
What is not in the picture are considerations around storage. IBM claims that the same amount of eMails on a Domino system needs substantial less storage than on Exchange, but that calculation is up to you (keep in mind how to configure a high performance server). Lesson to be learned: always ask any vendor to list out the machines they will need. More to come.

Posted by on 22 March 2010 | Comments (4) | categories: Show-N-Tell Thursday


  1. posted by Bill on Tuesday 23 March 2010 AD:

    Ask HP how well they did Sizing the Philips Exchange network, and why they had to double the infrastructure footprint mid-flight.

    ---* Bill
  2. posted by Patrick Picard on Tuesday 23 March 2010 AD:
    I look forward to the OCS vs. Sametime comparison. Please include a Sametime 8.0.2 and Sametime 8.5 Scenario.

    I know in the yellowsphere, we keep touting that we use less servers....but looking at ST 8.5....the tide might be turning :(
  3. posted by Brett on Wednesday 24 March 2010 AD:
    For Sametime "Classic" you only need the one server to provide ST for the "built in" ST client in Notes R8.x So it's still pretty excellent and self contained.

    Unfortunately yes for standalone Sametime you do need half a dozen servers to make it work ;-( I was kinda disappointed when I discovered that too.
  4. posted by Sjaak Ursinus on Wednesday 26 May 2010 AD:
    Stephan, thank you for reading our blog article ! Well as cross posting I want to attend your readers as well we are doing a Domino vs Exchange comparison as well ! We also do this in a series form as the content of the 2 products is to much to cover it in just one article. Our blog is in dutch so you have to translate (via google or so).

    { Link }