Often when setting up a backup schedule, you do not want a backup to run when another is running. For example, if you have a weekly and a daily backup, you do not want the daily backup to run on the day when the weekly backup is running.
For BE 2012, this can be easily accomplished if you observe a couple of simple rules.
All the backups must be in one backup job.
All the backups must start at exactly the SAME time
If these conditions are met, then the backup with the least frequent schedule would be run
Take a look at these backups
The first backup job has two backups, a full backup which runs on Fridays and a daily incremental backup. Both these jobs start at 11 p.m.
The second backup job has only a full backup which runs yearly on the first Friday of July. It also starts at 11 p.m.
The BE calendar below shows how the backups would be run on the first Friday of July
As you can see, the daily incremental backup is superseded by the weekly full backup. This is because the weekly backup is run less frequently than the daily backup. However, note that the weekly backup is not superseded by the yearly backup because the yearly backup is not in the same backup job. If it is in the same backup job, then it will superseded the weekly backup because it is run less frequently then the weekly backup.
Let's see what happens when the starting time of the backps is not the same.
The daily incremental backup is now changed to run at 11.01 p.m. while the weekly full backup still starts at 11.00 p.m.
You would notice that the daily incremental backup is not superseded like before. This is because it does not start at the same time as the weekly full backup.
Do note that all these superseding rules do not apply to duplicate jobs which you add as duplicate stages to the backup job.