A device maintains one archive at each destination it backs up to. Backup sets that share a destination back up into that same archive, so some settings are combined as a result:
- File exclusions defined in any set are applied to the entire archive, regardless of which set backed the data up.
- Only the highest-priority set's version and retention settings take effect.
All other settings, including schedule and priority, remain independent. The sections below explain both behaviors and give examples.
When this applies
This behavior affects you if all of the following are true:
- You have more than one backup set
- Two or more of those sets back up to the same destination
- The sets have different file exclusions or different version and retention settings
Backup sets that use different destinations are not affected. Each destination holds its own archive, with its own exclusions and retention settings.
If you have not yet set up this configuration, assigning a separate destination to each set avoids the complications described in this article. See Backup set best practices.
How file exclusions are applied
Backup Set 1 and Backup Set 2 both back up to the same destination:
-
Backup Set 1 excludes files ending in
.mp3,.mp4, and.wav - Backup Set 2 has no exclusions
Backup Set 1 does not back up these file types at all. Backup Set 2 does back them up, because it defines no exclusions of its own. Those files will not remain in the archive.
An exclusion always prevents its own set from backing up matching files. It does not stop other sets from backing those files up. Instead, the exclusions from every set using the destination are applied to the whole archive during the pruning stage of archive maintenance, and any matching data is pruned regardless of which set backed it up.
Files can appear backed up and still be removed
If any set on a destination excludes a file, that file is pruned at the next archive maintenance, even when a different set backed it up successfully.
Until maintenance runs, the file is present in the archive and appears to be protected. When files disappear from a destination, check the exclusions on every set using it, not only the set that contains the files.
How version and retention settings are applied
Backup Set A and Backup Set B both back up to the same destination:
- Backup Set A removes deleted files every day
- Backup Set B never removes deleted files
The result depends on which set has the higher priority:
| Highest-priority set | Result at the destination |
|---|---|
| Backup Set A | Deleted files from both sets are removed after one day. |
| Backup Set B | Deleted files from both sets are never removed. |
Both sets continue to capture new versions according to their own frequency settings. The difference appears during archive maintenance, when the lower-priority set's retained versions are reduced to match the higher-priority set's retention settings.
How restore works when sets share a destination
Restore is organized by destination rather than by backup set. When you click Restore Files, the restore menu opens on a destination and displays every file that destination holds for the device, across all backup sets that back up to it.
Files are not grouped, labeled, or filtered by the set that sent them. This means you cannot restore one backup set independently of another set that uses the same destination. You can still restore part of your data by selecting the files and folders you want, but there is no way to restore everything from one backup set as a single action.
How completion times are reported
When multiple backup sets share a destination, the completion time shown for that destination reflects the most recent time that any set finished backing up to it. It does not identify which set completed, and it does not indicate that every set is complete.
This applies to both:
- The Device Details screen in the CrashPlan console
- The backup status report email
To confirm the status of a specific backup set, check that set directly in the CrashPlan app.