Minimizing Your Footprint

I recently participated in an MVP chat, and we got an interesting question about SharePoint storage requirements. I answered the question as well as possible given the chat format, but the issue really deserves a more thorough treatment.

Reading through the SharePoint 2010 system requirements you quickly come across one that seems a bit strange. SharePoint is asking for 80 Gigabytes of hard disk space! We all know that SharePoint itself isn't that big, so where is that requirement coming from? Not only that, but where is that space actually required? And, can it be moved around?

Here's the kicker - SharePoint itself doesn't actually "require" that space, Windows does (in a way). But, SharePoint knows this, and will give you warnings in Central Administration if your C: partition doesn't have double your "physical" RAM free. This is because when Windows crashes, it creates a memory dump on the system volume, and needs free space to do it. In addition, Windows sets up a hard drive cache for swapping chunks of memory around - that's also usually around double your RAM. Further, if you have a hibernation file on your hard drive, that's also going to be the size of your RAM. Finally, you need the space that Windows, SharePoint, and any other applications actually do take up. And a little bit of buffer, so you can actually do some work.

If you've got 8 GB of RAM (the minimum recommended for a SharePoint production environment), that adds up pretty quickly. Hence, the storage requirements. Now, some of these pieces can be easily shifted around in Windows. Most servers don't need a hibernation file, for example, and you can easily move the swap file and dump locations onto other volumes. Then you can go into Central Administration's Health Monitoring to tell SharePoint to not monitor the drive space, so you don't get the warning (I haven't found a way to tell SharePoint to monitor a different drive, unfortunately). But there is still more going onto drive C: than many corporate Windows Server administrators like.

SharePoint Stuff you Can and Can't Move

Let's get this out of the way right up front. You can't tell SharePoint where to install certain things. The core of SharePoint - the "SharePoint root" or "14 hive" - is always going to be installed on your system drive (usually C:), in "\program files\common files\Microsoft shared\Web Server Extensions". That's where it goes. You can't configure this during Setup. You can't move it after the fact. Learn it. Live with it. Embrace it. Love it.

Other stuff, however, can be controlled. Just not always easily. Let's get the easy stuff taken care of.

• Your SharePoint content (the stuff you actually store in your sites) is going into SQL Server. You usually have full control over this, but there are lots of articles discussing SQL Server configuration so I'm not going to go into the gory details here.
• On versions of SharePoint other than Foundation, you can configure where certain non-core SharePoint components are stored during Setup. That's where things like search indexes go. But that doesn't change the location of the SharePoint root as described above.
• You can control where SharePoint stores certain log files. By default, those go into the SharePoint root, but they can be configured in Central Administration to be stored just about anyplace you please. Given how large these can grow, you almost certainly want to move them, and enable compression on the target folder.

SharePoint is also dependent upon Windows' Internet Information Services (IIS). When you activate the Web Server and/or Application Server roles on Windows Server 2008 and 2008 R2, several IIS components are pre-configured to be hosted on the system drive - most notably the INETPUB folder (which hosts your SharePoint Web Applications) and the IIS log files that get stored in the Windows\System32 folder (which can also become huge). In versions of Windows prior to 2008, it was an easy enough task to tell IIS to move these to another location. Not so with IIS 7.x and Windows Server 2008. Try as hard as you might, you won't find that configuration information in the management console.

Fortunately, these things can be moved. Unfortunately, moving them can only be done through the command line, and the commands to do it aren't trivial. The best instructions I've found for this are on IIS Program Manager, Thomas Deml's, Blog. In this, he not only describes the commands needed, but gives you a batch file to move the IIS root. Unfortunately, even Program Managers aren't immune from typos, and his batch file actually contains a couple of extra "\" characters. I've corrected the file, and made it available for download here. This batch file should be run after you install the SharePoint prerequisites, but before the actual SharePoint setup. Just as with the SharePoint logs, you should compress the folder you're storing the IIS logs in.

Summary

That's about it. SharePoint's requirements do state that you need 80GB of hard drive, but as you have seen, that statement is a little fuzzy about the why and where you need it. Although the default is drive C, many corporations have policies limiting what you do on the C drive. In this article, I've described how you can move many of these items around. I hope this has given you the information you need, or at least food for thought.