One of the things that you will need to decide before you install MetaFrame XP is whether or not you want to remap your server drive letters. Essentially, this option gives you a one-shot chance to change the current server drive letter assignments. By default, this will change current server drive letters from C, D, E... to M, N, and O...
You're given this option during the MetaFrame XP installation unless you're installing MetaFrame XP from an .MSI file. IFor MSI-based installs, drive letter remapping is not an option during the installation, and you must remap your server drives before installing MetaFrame with the DriveRemap.exe utility contained in the MetaFrame XP installation folder on the CD. If you choose either one of these drive remapping options, the utility will make the necessary changes in disk administrator and scan the registry looking for references to the old drive letters and changing them to the new drive letters.
Why does it matter in a MetaFrame XP environment what drive letters your servers use? It matters because MetaFrame XP has the ability to automatically map client devices’ disk drives to their session within the MetaFrame XP server. Typically, client device’s drives begin with C: and move up from there. A default MetaFrame XP server will also have a C: drive. When a user connects to sessions in this type of environment, the C: drive refers to the drive on the MetaFrame XP server. In order to map back to the client’s C: drive, another drive letter must be used (default V:). While there is nothing technically wrong with this scenario, it can be confusing to users because they see their local drive as C: when using local applications and see it as V: when using MetaFrame XP applications.
By changing the MetaFrame XP server drive letter to something other then C: the sessions on the server have the C: letter available for client use. Users access their local files on the C: drive regardless of whether they are running local or MetaFrame XP applications.
There are some people who have chosen to remap server drives only to discover at a later time there is a reason that the server must access its own local drive as C:. If this is the case, you can use the subst command to add a mapping to the root drive as C:.
For example, if your system drive is M:, you can execute the command subst c: m:\ from the command prompt. This will give you a C: drive that is identical to the M: drive. It is important to note that this is a temporary command.
Any substituted drives will not be retained when the server is rebooted. If a drive substitution needs to be permanent, you can add the subst command to a login script.
Advantages of Remapping Server Drive Letters
- Users will be able to see their own local disk drives as the correct drive letters.
- If you need to change the drive letter, the MetaFrame XP installation program provides an easy way to do this.
Disadvantages of Remapping Server Drive Letters
- Any previously installed applications will most likely stop working.
- In some situations, weird things happen on the server.
So now that you know how to remap drives and what happens during the remapping process, there's one question left--should you remap drives?
First and foremost, server drive letter remapping is only necessary when users will be accessing data on their local client devices from MetaFrame XP sessions.
There is a bit of controversy in the industry as to whether drive mapping is safe. Some people have noticed that strange problems have occurred in drive-remapped environments that could only be fixed by rebuilding the servers without remapped drives. They point out that Citrix must be aware of this, because they themselves pulled the remapping function out of the MetaFrame installation procedure starting with SP2/FR2.
Then again, there are plenty of environments where MetaFrame server drive letter-remapping has been in place for years with great success, so it's not like it always causes trouble.
In the real world, it's probably safest to only remap your server drives letters if you absolutely need it.