Archive server availability and fault tolerance considerations

The Archive Server should not need High Availability. This is because the archives are only uploaded once per day. The risk for data loss is only between that upload period and the Archive database backup procedure. The archive procedure also supports archiving to files. This allows two versions of the data to be stored on two different servers, making your data safe.

Note: Archive and Purge was tested in both VMware and Hyper-V virtualized environments during controlled Live Migration and Fail-over scenarios due to power failure or network failure. Both operations fully recovered and no data loss was observed.

The following diagram illustrates a suggested plan for scheduling Archiving and backups on the various servers so that potential data loss is minimized. This is accomplished by making sure that the Daily MES database Complete Backup and the Daily Archive Database Backup are not performed at the same time as the Archives/Purge. Also, the Daily Archive Database Backup should be performed after the daily archive data has been received.