Backup and disaster planning for exchange

I am fairly new to Exchange/Windows server systems and would like to be led in the right direction regarding data protection on Exchange 2003.  Specifically I am looking at all options with regard to restoring a failed server.  What data absolutely must be backed up for a succesful restore.  The message store(s) I assume are required but I am also hearing that the transaction logs should be backed up as well.  What else should be protected? It is also recommended to house the transaction files on a redundant storage system such as RAID 1 or better.  How often are transaction logs updated and why cant they just be maintained with the backup of the message stores?
At a minimum what we be required for a succesful restore?  Assuming I have a failover site, can you recommend an economical way to cluster/load balance scenario.  Lastly, does clustering require both servers to be of the same hardware specs?
Any recommended reading on clustering/load balancing other than from Microsoft?
Lots of questions so I will award 500 for the best information in the areas concerned.
Who is Participating?
I found this webcast pretty informative.

Usually, you would want a backup of the mail server (for configuration of the server) and your message stores.  Use a backup software like Backup Exec to help you along (using the Exchange Agent).  When you run a backup, it usually purges the transaction logs.  You would deselect the files associated with the stores and just use the Agent to select your stores.

There are software solutions like DoubleTake, GeoCluster, Avail and NeverFail to do failover, but I don't know if they really qualify for economical.  Microsoft Clustering does not require the hardware to be exactly identical like old solutions such as SFTIII did, but similar specs is typical.

Check out DoubleTake's and VEritas sites for additional cluster, highly available reading.

Microsoft has a guide, but I found it hard reading.


The location and backup of the transaction log files is important due to the fact that these log files store the data that has not been committed or written to the database. This data is stored in the transaction logs to allow for increased performance of the Exchange database. As a result the transaction logs hold critical information required to bring the ssytem back to a consistant and up to date status.

If the database suddenly stops due to a hardware error, software error or similar the transaction log files are used in recovery of this data. For example if you backup the database each night at 1 AM any transaction log files that have not been committed to the database are committed at this time and then deleted from the system. The current transaction log file which is named E00.log for the first database is not committed or deleted. From 1 AM onwards all changes to the database are stored in subsequent transaction logs. Each log file is 5MB in size as the E00.log file reaches 5 MB it is renamed to an incremental number i.e. E000001.log, etc.

Therefore if the disk system that holds the database fails at 1 PM the next day you can restore the database from the previous nights backup at 1AM. However if the disk subsystem that fails also stored all the transaction log files then you would not be able to recover any changes to the database that occured from between 1 AM and 1 PM. These changes including mail sent and recieved would be lost.

If the logs were stored on a independant set of disks then you would be able to restore the database form the backup at 1 AM and then re-play the log files that were created and stored between 1 AM and the time of the failure in order to commit the changes and have the data available to the users on the database.

This can get pretty complicated but I would suggest you look at the following article. Quite frankly I may have only confused you further.

DuratekAuthor Commented:
Thank you both...excellent information pls allow me to review the links you have provided and I will check back with you.
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.