Backup / Restore of Microsoft Exchange Server (VSS-aware) backup sets
Creation Date: May 18, 2010
Revision Date: October 16, 2018
Product: DS‑Client (Windows)
Summary
This article covers various backup / restore issues for Microsoft Exchange Server backups (using the VSS-aware backup set type).
Database backup policy (VSS-aware sets)
Database backup policy options can help reduce the backup time for very large databases (where the dump takes up significant time).
You can configure the backup set to perform differential database backups. Differential backups contain all the changes to the database since the last full dump.
Full dump: Always | [Default] This is the default behavior for all Microsoft Exchange Server backups. Each backup of the Exchange Server performs a full dump (VSS Snapshot) of each database. |
Full dump: Plus Differential | Performs a full dump (VSS Snapshot) of the database on first backup, followed by differential backups until another full backup is needed (*). |
Full dump: Plus Incremental | Performs a full dump of the database on first backup, followed by incremental backups until another full dump is needed (*). |
(*) A full dump is needed (other than first time) when: • a database has been backed up by another backup set (or manually from the Exchange tools); • a database has been restored (either from another database or an earlier generation); • the database properties have been modified (recovery model switched to ‘simple’); • a set number of consecutive differential backups have been performed, unless over-ruled with the Do not start full dump option. This uses the same number set in the DS-Client Advanced Configurations MasterGenerations parameter (note: this parameter is also used for another purpose). |
NOTE: DS-Client can take advantage of the differential backup policy if the backup set (of the Exchange database) is the only process that backs up that target. If another backup set is used to backup the database (or the internal Exchange commands are used to perform manual backups / dumps), then the backup policy requires the next backup to be a full dump.
Database Backup Policy Full Backup Schedule Over-ride Rules:
These rules are optional. They allow greater control when a Full Backup can occur (e.g. not during business hours).
IMPORTANT: Full dumps can be delayed, but a full database dump needs to be performed at regular frequency to protect the integrity of the database backup. By default, DS-Client allows a full backup to be skipped a maximum of 120 consecutive times. This number is configurable using the advanced parameter
MaxNonFullDumps. For more information, see
“Configuring the advanced settings”.
Data integration issues
Each Exchange database is presented as a component by the Exchange VSS Writer. In the VSS-based Exchange restore, a component must be restored with all its contents (the file snapshot) based on the rules specified in its Metadata.
These issues are similar to those in VSS-aware backups of Microsoft Hyper-V.
Truncation of transaction log with VSS-aware backup sets
The truncation of transaction log files is controlled by Microsoft components. How the truncation is triggered differs depending of the kind of backup being performed (for example, non-DAG configurations versus DAG replicated configurations). For more information, see Microsoft Developer Network documentation.
Restore issues
The DS-Client can only restore a Microsoft Exchange mailbox database if the destination database for the restore is in ‘mounted’ state.
DS-Client performs the following steps during a restore of a Microsoft Exchange Server (VSS-aware) backup set:
1. Checks if the destination database for restore is in ‘mounted’ state.
2. Retrieves information from the mounted database, including physical path and database GUID.
3. Dismounts the database.
4. If restoring to the original location: Replaces the database files in the physical location. If restoring to an alternate location: Restores logs to a “restoredlogs” folder, then restore the Exchange database files to the physical location. VSS Writers will apply the logs from the restoredlogs folder and then the directory will be removed.
5. Mounts the Microsoft Exchange database.
File restore to recovery database (RDB)
A direct VSS restore to a Recovery Database (RDB) is not supported. However, you can use the File Restore method to restore the backup files, then manually load those files to the RDB.
1. Restore the Exchange files before creating the RDB.
a) DS-User > Restore Now: In the Restore Wizard click File Restore.
b) For each database you want to restore, select the entire backup folder (including all log files).
c) Restore to the original or alternate location, as required.
2. When you create the RDB, specify the restored database name.
3. Before mounting the database, run the “eseutil” in the database directory, which will reset the database to a clean shutdown state. For example:
eseutil /r e00 /i /d
4. Mount your RDB.
NOTE: Only one RDB can be mounted at a time.
Item-level restore
VSS-aware backups of Microsoft Exchange Server have a granular restore capability that allows you to restore at the individual item-level from a backed up Microsoft Exchange database.
Requirements:
• The backup must be made using the VSS-aware backup set type.
• The target Exchange server where you want to perform the Item-Level restore must have DS-Recovery Tools installed and running. This is a separate installation. For detailed instructions, see the Client Software Installation Guide.
• The DS-Recovery Tools service account must have access to the Microsoft Exchange server where the items are going to be restored.
There are two steps to performing a Granular Restore: Step 1) Restore the database and Step 2) Restore Items. The first step restores the Exchange database at the point-in-time that contains the items you want to restore. The second step involves connecting to that database and selecting the individual items you want to restore.
1. Browse the Backup Sets tree and select the one you want to restore.
2. On the Restore menu, click Restore Now. The Restore Now Wizard appears.
3. On the Select the Restore Method page, select Granular Restore and then Step 1. Database Restore.
NOTE: If you are restoring from a BLM Restorable Image or Disc/Tape media, you can only perform Step 1 - the database restore from that media. Step 2 must always be performed from the database restored in Step 1.
4. Click Next.
5. On the Select directories/files to restore page, select the Exchange database to restore.
6. Click Next.
7. On the Select restore location page, choose where you want to restore the database and log files.
In general, it is easier to restore both the database and the log files to the same location. Remember, you are only restoring these files temporarily so that you can perform Step 2 (the Item-Level restore).
8. Click Next.
On the Select restore performance options page, the options are intended for large backup sets in high performance environments. In general, you should use the defaults and skip to the next dialog box.
9. Click Next.
10. On the Select restore options page, select the Exchange database restore options and then click Finish.
The restore process begins. After the database has been restored to a Microsoft SQL server, you can proceed to step 2 (restoring at Item-Level).
11. Browse the Backup Sets tree and select the same backup set. On the Restore menu, click Restore Now.
12. On the Select the Restore Method page, select Granular Restore and then Step 2. Items Restore.
13. Click Next.
14. On the Select database restore location page, select the target Microsoft Exchange Server where you want to restore at item-level from the restored database.
NOTE: The Microsoft Exchange Client Access Server you select should be running the DS-Recovery Tools (separate installation required). If it is not running on the same machine as the Microsoft Exchange Mailbox Server, specify the machine in this dialog box. The DS-Recovery Tools (DS-MLR) service should be running.
15. Click Next. On the Verify Prerequisites page, wait until DS-Client completes the compatibility check for the selected restore location. You can only continue when all prerequisite checks have passed.
16. Click Next.
17. On the Select EDB file path and log folder path page, specify the restored database from Step 1. Database Restore.
18. Click Next.
19. On the Mount Recovery Database page, DS-Client takes the selected Microsoft Exchange database file and prepares it for Item-Level restore.
You can proceed to the next dialog box only when all checks have passed.
20. Click Next.
21. On the Select E-Mails for Restore page, configure the list of mailboxes and emails for restore.
22. To restore an entire mailbox, click Mailbox.
a) In the Source Mailbox section, select the one you want to restore. You can select one mailbox per pass through the wizard.
b) In the Source Folder section, select the folders to restore from the mailbox.
c) Click Next.
d) Select the target destination mailbox and folder for restore.
e) Click Finish.
23. To restore specific emails, click E-Mails.
a) Enter the search filter you want to use. The wizard will search for emails matching your input.
b) Click Next.
c) Select the mailboxes that you want to search.
d) Click Next. The Wizard will search only mailboxes in the Selected Mailboxes list.
e) Select the emails that you want to restore from the list in the top section, and then click Add.
f) Repeat until you have added all the emails you want to restore.
g) Click Next. Choose the destination where you want to restore.
h) Click Finish.
24. On the Select E-Mails for Restore page, continue adding mailboxes and emails until you have completed your restore selection, and then click Next.
25. On the Select restore options page, select any restore options.
26. Click Finish.