There are several configuration settings that control how backup jobs/devices/media handle overwrite and append.
The Quick answer, you likely need to set your jobs to append to media then overwrite if no appendable media found. Additiona Things to consider;
1. The Backup device can be setup with a limit on each backup file created by BE. This will cause new files to be created, even for one backup job. i.e.. backup size is 200GB and the max file size is set to 100GB, you'd end up with 2 backup files for that single job. ( there are several other important settings for B2D devices as well, i highly suggest you look them over carefully)
2. Backup Media Sets, (this is likely where your confusion is coming in) your media is kept in a BackupMedia Set. This is a container that allows you to control overwrite and append periods for you media. i.e.. you may not want tapes overwritten for 2 weeks, even if the job says "overwrite". The media set configuration controls whether media is overwritable or appendable. Overwrite period for media starts from the time a job finishes to it. i.e.. if you start a job at 13:00 and it takes 2 hours to run, setting a 1 day overwrite protection on the media will cause it to be protected from overwrite until 15:00 the following day. So when your 13:00 jobs goes to run the next day, it can't overwrite the media (it's protected from overwrite until 15:00) Thus new media will be created on the B2D job.
3. Backup Job, where you can set overwrite/append etc... This setting for the job is independent of the media. If a job is set to only append to media, it will search for appendable media or fail if it cannot find any. If a job is set to overwrite, but no overwritable media is available (because the media set contains no overwritable media) your job will fail or new media will be created.
One thing you mentioned is you have three seperate jobs. So my thought is the following may be occurring; Job one runs, creates media001 and finishes. The Media Set is configured for 1 day overwrite, so the next two jobs (if set to only overwrite) start to run and first look for existing media to overwrite. Because your media set overwrite protection is set to X the existing media can't be overwritten, thus new media is created.
So, to fix your problem... look over the configuration items I mentioned. if you still need help answer the following questions for me;
1. Go to the Media tab, open properties for the media set in question and tell me what the overwrite and append periods are.
2. Go to the Devices tab and open the properties for your B2D device and tell me what your B2D max file size setting is set to.
3. How large are the jobs your running and how long is it taking? What days do they run?
Hope that helps
