Advantages of Backing Up Exchange Server Using Microsoft DPM 2007

Advantages of Backing Up Exchange Server Using Microsoft DPM 2007

Microsoft System Center Data Protection Manager 2007 (DPM 2007) provides you with one of the most efficient and reliable methods to backup and restore Microsoft Exchange Server.

Here are some of the top benefits:

Consistent Backups

DPM 2007 can be configured to consistently backup Server transaction logs every 15 minutes. These consistent backups help you in two ways:

• Consistent Server backups with DPM 2007 considerably bring down the problems associated with volume failures. For example, consider that you use normal Exchange server to backup the transactions logs and you made the last backup the previous night. Now, if the volume comprising the transaction logs fails, you may lose several hours of data. However, DPM 2007 can backup Server transaction logs every 15 minutes. Therefore, you will not lose more than a few minutes of data if the volume with the transaction logs fails.
• The Server is freed from the task of making huge backups late at night. By default, Exchange is configured to perform several maintenance activities at night. With huge backups being taken, the server becomes quite slow and other maintenance processes may fail to complete on time. With consistent backups taken with DPM 2007, you can prevent huge backups at night and have your Server running at its top performance for a long time.

Difference Between Exchange Server Backup and DPM Backup 

To understand the benefits of DPM 2007, you need to know difference between the working of exchange server backup and DPM backup.

Working of Exchange Server Backup

Usually, in Exchange, all transactions are written to transaction log files on the server and not to the database. When the current transaction log fills up, a new transaction log file is created.

Now when you perform an online backup:

1. The information store database is written to the disk. Simultaneously, data keeps getting written to the current transaction log.
2. After the database backup to the disk is complete, the current transaction log is closed, even if it is still empty.
3. Next, a new transaction log is generated.
4. Post this, all transaction logs that are closed, are backed up and committed to the database.
5. Finally, files of these committed transaction logs are truncated.

Working of DPM 2007 Exchange Server Backup 

Although DPM 2007 also deals with Exchange Server transaction logs and information store, its approach to the task is completely different.

1. When you install DPM 2007 on your Exchange Server, the DPM agent makes a baseline copy of the server.
2. Post this, two processes run simultaneously to protect the data on your server:

• Process 1 - Synchronization of Transaction logs: This task is done based on the protection schedule of your server. You can set it to occur every 15 minutes.
• Process 2 - Express Full Backup of Server Information Store: In this process, DPM uses Exchange 2007 Volume Shadow Copy Service Writer (VSS Writer) to identify the database blocks that have been modified since the last express full backup. These modified blocks are then copied to the DPM server. Because only changed blocks are copied, the backups take less disk space and less time to complete.

With the help of DPM 2007 you can have up to 512 express full backup copies of the Exchange Server database.

These express full backups taken using DPM 2007 are equivalent to full backups taken using Exchange Server. What makes DPM really beneficial is that these backups take very little time to complete and require much less storage space. Also, the consistent backup process brings down the data loss probability by manifolds.