Suggestions for Operating Autochangers

This section provides additional suggestions to help you use your autochanger and backup media effectively and reliably.

Recycling Versus Adding More Backup Volumes

Backup can save files on volumes marked appen (appendable) in the Volumes resource. If the volumes inside the autochanger are marked full, they cannot receive additional backups.

You can do one of the following with volumes marked full:

• If you need to keep the volumes for long-term storage, remove the full volumes and replace them with new media.

• If you do not need the data on the full volumes, you can manually change the mode to recyc in the Volumes resource. Backup overwrites the data with new backups, but maintains the existing labels. This is the only instance where you do not need to relabel a volume to make it eligible to be overwritten with new data.

The mode of a volume is automatically changed to recyclable when all the save sets on the volume have passed the time period specified by its retention policy.

There are advantages to both recycling media and adding more media to a pool. By recycling, you reuse the same volumes and do not add new volumes to the pool. However, the media may wear out over time and have a higher failure rate.

On the other hand, if your site requires that you maintain the backups in storage for a certain period of time, then you may have to add more media to the volume pool instead of recycling it. For example, an autochanger may need new volumes every three months if your company policy is to maintain the backups for a year. In this case, you have to keep adding new media to the pool until you can recycle the volumes that contain expired or old backups.

Using Pools with an Autochanger

If you plan to have full and nonfull backups, we recommend that you estimate the number of volumes needed for your full backups and assign them to the Full pool. This ensures that your full backups are in a consecutive range of slots in the autochanger, which makes it easy for you to remove all the volumes at the same time.

Calibrating the Devices

Check the autochanger manufacturer's documentation for information about the frequency and method for calibrating the loading mechanism for the autochanger device.