What are some server and data migration best practices for backup?

Every data and server migration is different, as are the procedures used to ensure a successful one. Every migration, though, carries with it a responsibility for ensuring the protection of the migrating data.

Myspace, for example, recently lost a huge amount of data during a server migration. There are data migration best practices for backup that can cut down on the likelihood that an irreversible failure like the one suffered by Myspace -- and its users -- will happen.

For server migrations, leave the original data source untouched, if at all possible. Suppose, for example, that you have just copied data from one server to another, and the migration did not give you the results you were expecting. If the original server was left unaltered, then you can revert back to using that server until you can figure out what caused the migration to fail. If, on the other hand, you had purged or otherwise altered the original server's contents, then using that server as a fail-safe would not be an option.

Always create a full backup of the systems you plan to migrate before performing the actual migration. This key element of data migration best practices holds true even if you plan to leave the original system unaltered. A backup gives you another layer of protection you can use in the event something completely unexpected happens during the migration.

You should also determine what other systems might potentially be affected by the migration process and back those systems up as well. There are certain types of migration failures that can keep you from being able to put things back to normal simply by using an unaltered server or restoring a backup. Best practices for backup include covering yourself from these failures.

One of the best examples of this failure is one that occurs while migrating to a new application version. Some application migrations modify the Active Directory schema or make other changes to AD that causes it to become incompatible with previous versions of the application. If a failure were to occur during such a migration, then restoring a backup would not work unless you also had a way of rolling back AD to its previous state, so apply data migration best practices here.