Exchange Server 2003 Disaster Recovery

Try as hard as we may, we will never be able to achieve the Utopian ideal of never having a disaster come our way. Since we are firmly entrenched in the real world, it makes good sense then to understand the disaster recovery process as it applies to Exchange 2000 Server and what needs to be done before the disaster strikes—the most important part of disaster recovery planning. A good plan for Exchange 200 Server disaster recovery revolves around and is intertwined with a good plan for disaster recovery for your Windows 2000 servers. We will explore the process and the relative levels of disaster recovery in the following sections.

The Rule of the Seven P’s

It some circles, the rule of the seven P’s rules supreme. For those of you who don’t know what the rule says…it goes like this: Proper Prior Planning Prevents Piss Poor Performance. I think the early coders had their own take on this rule when they came up with GIGO: Garbage In = Garbage Out. Either way you want to look at, the same moral holds true. In order to prevent disaster from becoming a truly disastrous event, planning and preparation must be done ahead of time. Little good does it do to try to recover after a disaster with an ill prepared plan.

The first part of disaster recovery preparation is putting a solid backup plan into place for your network. This actually goes beyond preparing for Exchange 2000 Server disaster recovery—if the entire Windows 2000 network is up in flames, the Exchange 2000 Server portion of it will matter little. You will find, however, that it is a lot easier and well documented how to recover the Widows 2000 implementation, especially if you still have at least one Domain Controller on the line functioning normally.

Your backup plan should include a well documented and easily implemented solution that produces routine backups (something such as Normal, Differential, Differential, Differential, Differential). Unfortunately, simply making the backups as planned will not provide you much in the way of disaster recovery if your entire building goes up in flames over night (I know you were wishing for that….). You should take steps to get the media stored off site in a secure fire-proof, water-proof storage location. Many companies exist solely for this purpose and will schedule media pickup and delivery, which will also keep you squared away in regards to media rotation.

Forty Days and Forty Nights

Should disaster strike, you should be well prepared for the recovery process if you have taken the steps required ahead of time. Of course, when it comes time to play magic man and get the network up and running again, you will need more than just your backup media. The following is a short (very short) list of things I would recommend to keep on hand in the event this sort of catastrophic disaster should find its way into your world:

• Replacement hardware that is identical to the original hardware.
• Software setup CD-ROMs; for Windows 2000 Server and Exchange 2000 Server plus any other applications your network requires.
• New routers, firewalls, WAN circuits and other network hardware devices as required for reconnecting your network.
• Good Internet connectivity if you plan on restoring the capability for sending mail across your firewall.
• Time, lots and lots and lots and lots of time—get the picture?

You have a couple of different levels of disaster recovery that are supported in Exchange 2000 Server. You can perform the following:

• Recovering an entire Exchange 2000 Server implementation
• Recovering a single Exchange 2000 Server
• Recovering individual Exchange 2000 Server databases
• Recovering mailboxes of deleted users

Now, let me clarify a little bit here…the first two items in the list above are truly disaster recovery situations that will require the full disaster recovery process as we will discuss in the next situation. The last two items in the list above are much simpler recovery actions, will require only minutes of your time and will not be discussed in this article.

The Heat Is On

When the day comes that you have to put your disaster recovery plan into action, you will find that the process is fairly simple conceptually, but can be much more difficult when it comes to actually executing it. Exchange 2000 Server provides a means within itself to help restore a system or server, but this must be done after rebuilding the Windows 2000 server itself. The basic process to perform a disaster recovery is outlined in the following steps:

1. Reinstall Windows 2000 Server on the computer, taking care to ensure that the following items are observed:
   
   1. Install the same version of Windows 2000 that you had installed on the server previously: Server, Advanced Server or Datacenter Server.
   2. Install Windows 2000 to the same volume and path as it was installed during the previous installation.
   3. Configure the server with the same name as during the previous installation.
   4. Configure the installation to have all of the components installed in the previous installation.
   5. Install Windows 2000 as a stand-alone server; do not join the server to a domain during Windows 2000 installation or thereafter.
2. Restore the system volume to the new server using NTBACKUP as follows:
   
   1. Launch the Backup utility by clicking Start > Programs > Accessories > System Tools >Backup.
   2. Click the Restore Wizard icon to start the restoration.
   3. Click Next on the Welcome to the Restore Wizard window to continue.
   4. From on the What to Restore window, choose the media and the backup set from within that group that you want to restore. If you do not see the media you want to restore from, click Import Mediato open a new window enabling you to browse to the media you wish to work with. Select the files within the group to be restored. Click Next to continue after making all of your selections.
   5. On the Completing the Restore Wizard screen, you can review the settings that you have supplied. If all settings are acceptable, click Next to continue. If the settings are not acceptable, click Advancedto configure advanced restoration options.
   6. On the Where to Restore window, you will need to decide the location to which the restored files will be copied. In this case (assuming that all volumes and paths have been created properly), you need to choose Original Location and click Next.
   7. On the How to Restore screen you will need to specify what to do if the restore process detects a file in the restore location that is the same as a file trying to be restored. In this situation, I prefer to select Always replace the file on disk, but you can make your selection according to your preferences. When you have made your selection, click Next to continue.
   8. On the Advanced Restore Options window, select which special options you want applied to your restoration and click Next to continue. If you want additional information on the advanced options, search Windows 2000 Server online help for “To set advanced backup options”.
   9. Click Finish on the Completing the Restore Wizard window to begin restoring the selected files.
   10. Click Close to finish the process when the restore completes.
3. Restore the system state to the new server using NTBACKUP by following the same procedure as for the system volume, but this time selecting the System State data to be restored.
4. Run Exchange 2000 Server setup in Disaster Recovery mode as follows:
   
   1. From a command prompt, launch the Exchange 2000 Server Installation Wizard in Disaster Recovery mode by entering X:\Setup\I386\Setup.exe /DisasterRecovery, where X is the location of the Exchange 2000 Server setup CD-ROM. 
   2. The window as shown in Figure 1 will open and you can then proceed to install Exchange 2000 Server as you normally would. Remember that you must select every component that was originally installed on the computer to the action Disaster Recovery. If originally installed components are not selected for Disaster Recovery, then you must manually select them.

Figure 1 – The Exchange 2000 Server Installation Wizard in Disaster Recovery mode.

3. An important note if you are trying to accomplish this procedure by using the Exchange 2000 Server online help files—The directions provided are wrong in that you are directed to use the following command to perform the Disaster Recovery installation: X:\Setup\I386\Setup\DisasterRecovery. As you can obviously see, this will not provide the desired result.
5. Restore the your Exchange 2000 Server databases using NTBACKUP by following the same procedure as for the system volume, but this time selecting the media and group that contains your Exchange 2000 Server databases. The following amplifying instructions apply to restoring databases. For more information, see the “Prepare to Restore Information” topic in the Exchange 2000 Server online help.
   
   1. Verify that the Exchange Server services are running on the server in question (a departure from previous versions of Exchange Server). See the “Monitor Services Used by Exchange” topic in the Exchange 2000 Server online help for more information on this.
   2. Dismount the databases to be restored. See the “Dismount an Information Store” topic in the Exchange 2000 Server online help for more information on this action.
   3. Select the media and databases to be restored. Click Start Restore to continue. Figure 2 shows this step of the process.

Figure 2 – Preparing to restore the Exchange 2000 Server databases.

4. On the Restoring Database Store window (shown in Figure 3), specify a directory to store the log and patch files during the restore in the Temporary location for log and patch files. Be careful to ensure that the specified location has enough disk space to store the files. DO NOT specify the Temporary location directory to be same as the original location of the database of log files, or the restore process will not work.

Figure 3 – Selecting a temporary location for the log and patch files.

5. If you are restoring a full backup without any incremental backups, select Last Backup Set to start log file replay after restoring the database. If you are restoring a backup with incremental backups, do not select this option until you are restoring the last incremental backup.
6. If you want the database to be mounted as soon as the restoration process is complete, select the Mount Database After Restore option.
7. To begin restoring the database, click OK.
6. You’re done—finally! Time to test and deploy your newly restored Exchange 2000 Server implementation. However, if you are running the Key Management Server, the Site Replication Service or participating in an Exchange 2000 Server cluster you will have additional work left to complete. I will discuss these scenarios in a separate article.

The process to restore a single server is the same as the aforementioned procedure for restoring an entire Exchange 2000 Server system. The only difference is that you will only be working with one specific server, and thus you will choose your restoration options accordingly.

Wrap-up

You may have noticed that you have to go through three restoration steps in this process: restoring the System Volume, restoring the System State and restoring the Exchange 2000 Server databases. If you try to restore system data and Exchange data, you will receive the warning dialog box as shown in Figure 4.

Figure 4 – Error when attempting to restore system data and Exchange data at the same time.

The NTBACKUP utility that ships with Windows 2000 is replaced by an updated version during the installation of Exchange 2000 Server. This updated version allows for online backups of the Exchange 2000 Server files.

Although no amount of preparation can prevent disaster from striking, you can take steps to minimize the impact of such a disaster when one occurs. Even though the process to get your network up and running again smoothly could take days or even a week or two, it’s still a better solution than having nothing at all to fall back on. Always remember the rule of the seven P’s and you will be in a much better position when the dreaded day comes to be.