Managing Devices and Media › How Media Pools Work › Media Maximization in GFS Rotation Jobs › Media Maximization Methods › GFS Rotation Jobs with Append Media Enabled

GFS Rotation Jobs with Append Media Enabled

Similar to submitting GFS Rotation jobs without the Append Media feature enabled, you can maximize media usage when you enable Append Media by submitting multiple jobs using the same media pool. In addition, enabling Append Media also lets you maximize media usage by allowing you to share tapes among different jobs, regardless of the backup method that was used. (The only exceptions to this is weekly and monthly backup jobs. Weekly and monthly backup jobs can never share tapes with full, incremental, and differential backup jobs.)

For example, when submitting multiple GFS rotation jobs with the same media pool without Append Media enabled, a tape that has data from a full backup job can be shared only with data from another full backup job. If you enable Append Media, a tape that has full backup data can be shared with full, incremental, and differential data.

To share tapes among different jobs with different backup methods, Arcserve Backup uses the same GFS rotation naming syntax, but it uses a different naming convention for backup types when the Append Media feature is enabled:

(backup type)-(user-defined media pool prefix)-(day-of-the-week)-(date)

If you submit GFS rotation jobs with the Append Media feature enabled, you can maximize media usage by submitting multiple jobs using the same media pool and use the previous day's tape within the current week.

For example, if you submit three GFS rotation jobs all using the same media pool and 5-day rotation scheme, all three jobs share the same set of tapes. In addition, multiple days can share the same tape, drastically reducing the amount of tapes you use:

• Monday, Tuesday, Wednesday, Thursday = One tape that includes full backup data from job 1(day 1), job 2(day 1), and job 3(day 1), and incremental backup data from job 1 (days 2, 3, and 4), job 2(days 2,3, and 4), and job 3(days 2,3, and 4).
• Friday = One tape that includes weekly backup data from job 1(day 5), job 2(day 5), and job 3(day 5)

This results in two tapes for the week.

Without the Media Maximization option, each job requires its own set of tapes. Among these tapes, only the ones that include data from the same Backup Method can be shared:

• Monday = Three full backup tapes. One tape for job1(day 1), one tape for job 2(day 1), and one tape for job 3(day 1)
• Tuesday, Wednesday, Thursday = Three incremental backup tapes. One tape for job1(days 2, 3, and 4), one tape for job 2(days 2, 3, and 4), and one tape for job 3(days 2,3, and4).
• Friday = Three weekly backup tapes. One tape for job1(day 5), one tape for job 2(day 5), and one tape for job 3(day 5).

  This results in nine tapes for the week.

Note: If you submit a GFS Rotation job with Append Media enabled and Arcserve Backup cannot use the previous day's media for some reason, it will format a media in the Scratch Set or a blank media using the “With Append Media” naming convention. To minimize the likelihood of this situation occurring, see Media Maximization Rules in this chapter.