Wednesday, December 1, 2004

Avoid Exchange Hell by using the C drive


By David Gewirtz

In my last "Hell" article, I talked about how having multiple domain controllers can keep you out of Exchange Hell. There's another tip that will also reduce your chances of going straight to Exchange Hell. And, again, you can learn from my mistakes.

"Put the Exchange application and databases on the C drive."

When we first built our Exchange server, we decided to do it "right." We set up a box with a C drive as simply the operating system drive, and then added a series of mirrored drives for applications, the Exchange database, backups, and miscellaneous shared files. The result was a monster with seven drives:

  • One C drive
  • Two D drives, mirrored (for applications)
  • Two E drives, mirrored (for the Exchange database)
  • Two F drives, mirrored (for backups and shares)

Here's your "Don't do as I do, do as I say" tip of the week: install the Exchange application and databases on the C drive. I don't care if you learned to put applications on a separate drive in MCSE school. I don't care if you like the idea of mirroring Exchange.

Just do what I tell you. Put the Exchange application and databases on the C drive.

After everything tanked, I attempted to do a restore from my images, and I couldn't get Active Directory and Exchange to restore. After three days straight, I finally figured out what happened. And it wasn't fair.

Active Directory uses a database called NTDS.DIT. Normally, this thing is located in C:&#92WINNT&#92NTDS&#92. However, for some reason, the original Exchange server located it on the E drive. When I tried to do a restore, and the E drive wasn't visible, NTBACKUP didn't tell me that it wanted an E drive. And when I did an authoritative restore on the database, I was doing so to the original install database, not the restore.

The fix involved moving the NTDS.DIT file from E to C, then going into the registry and finding every "E:&#92WINNT" entry and changing it to "C:&#92WINNT", including changing some of the hex entries.

There are a lot of registry entries to fix. Fortunately, I was able to download a program called Resplendent Registrar (dumb name, great program). This program has a registry search and replace feature and I was able, then, to go through and do all the changes I needed. It comes with a 21-day trial, so you can check it out.

Want to learn more about preventing Exchange Hell? Keep reading future issues.