Then click the save button.
If you'll select the second option, backups that are "Partially Successful
" due to VSS will now count as well:
Please keep in mind, that if you choose to ignore the output of scripts/VSS, you may end up with snapshots that are only crash-consistent instead of Application consistent.
It is recommended to resolve your problems with scripts/VSS instead of ignoring them.
Sometimes Partially Successful backups may be caused by N2WS trying to backup instances that do not exist anymore:
Go under Policy details and select the drop-down next to "Auto Target Removal " and change the setting to Yes and click on the Save button.
Another reason for not being counted toward the retention is it might be a failed DR:
You need to resolve the issue that is causing the DR to fail or to disable the DR.
Here's an actual example that will explain the Generations to save better:
CPM will cleanup out of retention snapshots (successful or failed) only when it has enough successful backups as you configured in your policy's retention (Generations to save).
Let's assume you have a daily policy that runs on 2 instances and is supposed to save 3 generations per instance so you expect to have 6 snapshots on EC2 after it ran 3 days and on, right?
On day 1 it runs and succeeds on both instances = 2 snapshots. Successful backup
On day 2 it runs but only the first instance is successfully backed up so now you have 3 snapshots. This is not considered as a successful backup.
On day 3 it runs again but only the first instance is successfully backed up so now you have 4 snapshots. This is not considered as a successful backup.
On day 4 it runs and succeeds = 6 snapshots (none is deleted because you only have 2 successful backups, not 3). Successful backup
On day 5 it runs and succeeds = 8 snapshots (none is deleted because you only have 3 successful backups) - on this day you'll pay for extra 2 snapshots. Successful backup
Cleanup process will still not clean the failed backups since they're still within the retention period.
On day 6 it runs and succeeds = 6 snapshots (day 1,2 and 3 snapshots are deleted). Here, cleanup will clean the older successful ones as well as the failed ones.
The good backups don't necessarily have to be one after the other but as long as you have failed backups between successful backups, the failed ones will not get deleted.
Lets assume we have the retention set to save 4 backups and we have the following backup history in the backup monitor (from oldest to newest, all for the SAME policy) :
Backup record 1: Backup of target instances failed
Backup record 2: Backup of target instances succeeded
Backup record 3: Backup of target instances succeeded
Backup record 4: Backup of target instances succeeded but DR of one of the instances failed
Backup record 5: Backup and DR succeeded
Backup record 6: Backup and DR succeeded
Now lets assume the next time the backup run for that policy, the backup and DR will again be successful -
Backup record 7: Backup and DR succeeded
What will happen is that the next time the cleanup process runs, it will clean some backup records as we have now 5 successful backup records.
It will clean records 1 & 2 as both are out of the retention, but it will not clean records 4(which failed DR) until record 5 is out of retention and cleaned.