Exchange is crucial for any organization and that’s the reason Microsoft comes up with effective changes with every version of Exchange server especially pertaining to backup and data recovery. On this note, Exchange Administrators have witnessed a major overhaul with Exchange 2010 which now comes with Database Availability Groups or DAG. DAG is the right solution to surpass SCR (standby continuous Replication) and CCR (Cluster Continuous Replication) limitations of Exchange 2007.
What is DAG and how it helps?
Current server system is a fully meshed failover/failback environment. With Exchange 2010, each Enterprise license server has 100 databases running on them and Database failover is done at database level. To elaborate, it is presumed that you have two locations – Site A and Site B at geographically different locations. Since Exchange server can host 100 Databases or DBs, Site A/Server 1 may have say 10 DBs, of which 5 DBs failover to Site A/Server2 and 5 databases failover to site B/Server 3. Similarly Site B/Sever 3 can also host say 20 Databases of which 10 each failover to Site A/ Server 1 and Site A/ server 2 thus supporting 16 copies of the database as high availability and disaster recovery of Exchange databases. This also ensures failover and failback in Wide area Network or WAN within 30 to 60 seconds.
Disaster recovery is established with the establishment of DAG. Read and execute the below mentioned steps to create Database Availability Group on Exchange 2010:
Step 1: Configure a Server with Windows 2008 SP2 or above OS. Install Exchange 2010 with Mailbox server role
Step 2: Launch Exchange Management Console and from the left tab, expand Organization Configuration
Step 3: Select Mailbox and select Mailbox Availability Group tab from the center-pane
Step 4: In the right pane, click on New Database availability group and assign a distinct name to DAG. Following the naming convention, name the File Share Witness path and directory (created earlier). Click on New
Step 5: The Wizard is completed. Click on Finish.
A new DAG is created. Now add members to the DAG with the following steps:
- Launch Exchange Management Console and from the left tab, expand Organization Configuration
- Click Mailbox. Next click Database Availability Group tab
- Right click on the DAG created earlier, and select Manage Database Availability Group Membership
- From the next window, click Add and choose the mailbox servers that you want to join to the DAG. Click Manage
- Click Finish, when all the necessary nodes are added.
System is now ready for configuration process
- Launch Exchange Management Console and from the left tab, expand Organization Configuration
- Click Mailbox. Next click Database Availability Group tab
- Right-click the database to be replicated within the DAG
- Select Add Mailbox Database copy
- Browse for the server in the DAG to which you want to replicate the mailbox database
- Select the Replay lag time and Truncation lag time
- Fill the name of preferred list sequence number and click Add
- Click on Finish after the process is over
A copy of mailbox database is created. Similarly, create more DAGs for database replication and ultimately Exchange server 2010 disaster recovery.
Exchange Administrators should consider the following points:
- Hardware configuration should support current load as well as future load when it acts as a master copy of mailbox database.
- All mailboxes should have distinct names.
- TCP/IP should be booked in advance to support current and future cluster needs.
- Take proper care for additional WAN traffic due to extra DAGs as per future demand.
- Power management should be disabled at cluster nodes both in motherboard BIOS and in the power applet in Control Panel. This helps in avoiding unwanted failover.
- Test failover and failback mechanisms after the configuration is finalized. Monitor the replicate between DAG notes to ensure replication health.
- In the DAG member nodes, run an additional network adapter for Windows cluster support.
Exchange server 2010 disaster recovery module works on failover failback mechanism in meshed environment, however, this environment also has limitations. If disaster recovery doesn’t work at some point of time, it is suggested to opt for data recovery. If, at some point of time, Exchange goes down or the data gets corrupt, install and repair corrupt EDB files with Stellar Phoenix Mailbox Exchange Recovery software.
Exchange servers have data files stored in EDB format. If there is some problem with Exchange server, files get corrupt and inaccessible. In such case, Stellar Repair for Exchange software selects the corrupt files, repairs these EDB files and renders these accessible.
How it works:
- Recovers offline EDB Files: Install and run the software on your system and use this tool to select the dismounted EDB file.
- Repair the dismounted and corrupt EDB files using Exchange recovery tool. Software is enriched with the facility to repair single as well as multiple EDB file.
- Repair the EDB files and export these directly to Live Exchange server.
- In case, you have to save select mailboxes, you can convert select mailboxes into either of the preferred format like MSG, EML, RTF, HTML and more.
- Easy to use interface lets you repair EDB files faster and enables faster Exchange server 2010 disaster recovery.
To summarize
Setting-up new Exchange server is time taking and tedious task. Secondly, it takes quite an effort to transfer all mailboxes with huge data. With options like Stellar Repair for Exchange, you can easily convert the corrupt EDB files into accessible mailboxes. Self-guiding user interface and easy to use procedure enables healthy database recovery within lowest possible time.
