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partitioning tips for Windows Small Business Server 2011 Standard

Roger Roman Jr
I am preparing for a Windows Small Business Server 2003 R2 Migration to Small Business Server 2011. I already have the Migration Guide from Microsoft and have read it a few times.  

It does not hint to the best partition setup to install the server / logs / etc.

I have (1) 250GB Hard Drive for the OS and (4) 320GB Hard Drives in RAID 5 using 3Ware Controller.  My previous installation I had sbs 2003 R2 on a single drive and had all SQL databases along with Exchange database and all users shares on the RAID.  

Question #1: How many partition should I setup for the installation of the OS?

Question #2: Should I install the OS on the RAID 5 with a partition of 120GB or should it the OS be on a separate Hard Drive non-RAID?

Any other tips that others may have come across while performing this same migration.

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Distinguished Expert 2018
I definitely recommend putting the OS on RAID. Spinning drives still fail often enough that this can really save time. Putting it on the same RAID 5 as the data can cause a performance hit though, so it really depends on how heavily you are using the system on whether you may want to reconsider your configuration. I would usually do a raid-1 mirrored for OS and raid-5 for data in most cases, but again, case by case basis.

As far as size, I wouldn't go smaller tha 150GB for the OS. Exchange and SQL are very different than they were in 2003, plan accordingly.


Unless you don't care much about downtime on this server, you should always RAID your OS drive.  That hard drive will fail one day, and then you lose your whole OS.  Ideally you want it on a different RAID array as well, but if you can't afford that or don't have access to one, then put it on the same RAID array.  This is far from ideal, but for a low transaction environment, and if exchange isn't eating up your metrics, then it'll be OK.  No use optimizing a server that's rarely peaking out.

Now, as far as migration.  You should start with freshly formatted drives when upgrading from 2003 to 2008.  2003 formatted NTFS which does NOT work well with SQL Server 2008 as you get disk alignment issues which reduce Disk IO performance by about 30%.  Remember to format the disks if they were on Server 2003!!
Kent WSr. Network / Systems Admin
At the very least, I would Raid1 the OS, will save big headaches long down the road.

If you are using SQL server on theses drives ( you mentioned SQL), I would highly recommend not using Raid5.

The answer would depend a lot on how much usable space you need.  If you can afford the taxation, I would setup the 4 X 320's with Raid 10.  Especially knowing and using the 3Ware controllers, they are good, but not as reliable as other more expensive brands.  

So are you installing SQL and Exchange onto this new system, also?  What you are installing and space requirements of each would help.

I would put  OS on  Raid 1 and Sql on raid 5  but ideal raid !0 i sbetter than raid 5 as it gives you better performance than raid 5 it might cost you but if you are planning for future  than that is the way to go Good Luck

It really depends on your data usage.  If you have fast disks and you're serving 3 users, or your current setup is just like this, and you're not planning on growing, then raid 5 is fine.  
Hard drives are cheap.  Buy another 250 so that you can create a mirror partition for the OS (assuming here that your RAID controller supports more than 5 drives).  Don't use up the entire 250 for the OS though.  If you partition off say 75GB from this drive you will have more than enough for your OS (and nothing but your OS).

Use the remaining 125 mirrored partition for your Exchange database.  If you are a performance freak you can drop the Exchange logs onto a partition crated from your RAID5 set on the 320's, but given that it is SBS you are going to get a "in theory" performance boost --- I would fall off my seat if you saw any real-world benefit.

Now that we have the OS and Exchange partitions taken care of on the mirrored 250Gb drives, lest consider the 4 320's.  I am an "old school" guy that grew up with mainframe and UNIX.  So of course I should tell you about all of the nice partitions you should make and how to size them.  Ready for this?  Just set those puppies up as one big partition (gulp!).  Use them as general user data.

Again, this is a SBS server environment.  Unless you are doing something rather unusual, chopping up your data drive is not going to gain a heck of a lot.

Now, if your RAID card does not support adding another 250.....Set up all your 320's as RAID5 and partition off 50Gb or so for the OS.  Then partition off another 100Gb or so for e-mail.  The rest for data.  What about that 250 hanging out there?  Use it as a utility drive for now (you know, junk you want to throw out there as an administrator....it is a great place for shadow copies too).

Roger Roman JrDirector of Information Technology


Thanks Guys....I will put the OS on a RAID 1.  My 3Ware controller only has 4 ports that I am using for my RAID 5.  Is it okay to use the the onboard Tyan RAID (ie soft raid) for the OS (RAID1)?  I really don't want to buy another $400 raid card.

I have around 24 users each with their own exchange mailbox.  Use to run Blackberry Enterprise server on 2003 but no longer will be using blackberrys in our organization.  Moved to iPhones
You have some sort of a baseline, your old system.  How was your old system configured and was exchange or SQL ever 'slow'?  If not, you're probably OK, but far from an ideal configuration.  

OS level raid offloads the RAID functions to your CPU which can cause CPU spikes, but it's not MAJOR.  I would never do it in my systems, but my systems handle terabytes of database data with millions of rows added every hour.  Yours has different patterns, so if your CPU is highly underutilized, you should be fine.  Test it out!  Build it out, test it out, and see how it performs.  

Most likely in your environment there won't be a tangible difference.  Us I.T. guys are crazy about best practices but shouldn't lose sight of the users scenario.
Roger Roman JrDirector of Information Technology


Thanks all. I appreciate all the advice.

Not familiar with Tyan specifically, but if it is on-board it is still hardware RAID.  Some of the on-motherboard RAID controllers are quite good for small servers.  I don't see any reason why you wouldn't want to use the on-board controller for a second mirror that houses the OS.

I will jump up and down on my soap-box that you should avoid the OS RAID built into Windows.  I have seen it fail way to many times.  But then, I suppose if you got nothing else it is better than running with no RAID.


IF you do have access to a on board raid controller, use it over Windows OS RAID.  If you don't, Windows OS RAID is better than no RAID per my experience.

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