What is the recommended size for a server 2008 system partition? I've seen 20GB as well as 49GB suggested but I can't seem to find any white papers or best-practices documents on the subject.
It depends... According to the official system requirements (http://www.microsoft.com/windowsserver2008/en/us/system-requirements.aspx) 32-bit installs of the OS need at least 20GB, while 64-bit installs require at least 32 GB. The OS itself takes up about 10GB if I recall correctly, but you need to factor in:
- Page file (typically 1.5x your physical RAM)
- Over 15% free space so that you can defrag
- Space for any applications you may install
- Space for the dump file (1x your physical RAM)
- Space for log files
With hard drives being as cheap as they are these days, I would recommend not skimping on space for the OS partition. Give yourself some extra room for things you forgot to factor in... it is much easier to allocate the space up front than it is to make space a year from now.
As far as cleaning up the Winsxs directory... don't. You will break future updates, MSIs, and Windows Update from working.
Even better... from the Windows 7 Engineering team, everything you need to know about Microsoft's engineering goals around disk space and the real size of the sxs folder (it's not as big as you think):
A real problem in previous versions of Windows was it was difficult to extend the size of the system partition, you needed to use third party tools which were a little dicey.
However, with 2008 they've included the ability to expand and shrink partitions, including the C: drive.
This means if you get it wrong to start with, you can probably rectify the issue reasonably easily. If you were using 2003, you'd be a right pickle.
To be honest, I can't imagine installing a Windows server with less than 40Gb as a bare minimum, ideally 60Gb or even 80Gb for the system partition.
As for WinSXS cleanup, you'll find a lot of people claiming you can do this and that, and Microsoft telling you to leave it alone apart from maybe one or two very specific issues. On a workstation I might be persuaded to experiment but on a server I'd be wary about betting against the vendor's suggestions.
Beware c:\windows\winsxs. This folder will infinately grow with "hardlinked" copies of system dll's. On a windows server 2008 64bit server we have running for approximately 1 year, this folder is 11GB in size. There was a recommendation of 100GB, I would highly agree with this recomendation. Plan for the future. :)
You need to account for software installations and any additional space those applications may also take up. Some software apps will only allow writing their data or caching files to the c:\ drive, so using anything less than 100GB is a huge mistake you will only make once. Proper planning avoids reinstallation.
Most new software apps on the market are bloatware. Allow for this.
Drive space is cheap, go 250GB. Better to have it and not to need it.