Yosemite Server Backup provides several default media rotation types. These type can be used as is or as examples for creating custom rotations.
No Rotation Type
When no rotation type is selected. the user may schedule the days to run on but Yosemite Server Backup will not manage the media. The user must supply the desired tapes each time the job runs and manage the reuse of older media.
Fixed Rotation Types
Media sets are named for the interval that has been run. They follow the form [Interval ] Set [ number ] .
- Fixed by day of week – for example, of a daily media set is "1st Monday ."
- Fixed by week of month – for example, of a weekly media set is "1st Week of the Month ."
- Fixed by day of month – for example, of a monthly media set is "1st Month ." An example of a yearly media set is "Yearly 1 ."
- Fixed by day of year – for example, of a yearly media set is "First Day of Year 1."
Daily Append
This is a special rotation designed for users with a single backup device. It is the only rotation that appends data to media. It will perform a full backup on the specified day followed by daily incrementals on the remaining weekdays. At the end of the rotation, the user must insert new media for the job to use. This rotation assumes that an entire week of backups will fit on a single media.
Simple and GFS Rotation Types
These rotation types specify combinations of full and incremental backups that efficiently use a specific number of media sets. The main difference between the Simple and the GFS rotations are that only the GFS rotations specify Yearly backups.
Custom
Select this option to create your own rotation.
Rotation Types Compared
Yosemite Server Backup provides a variety of media rotation types to select from. Or, you can define your own media rotation.
The following table compares the historical backups and full data recovery capabilities of each of the rotation types provided in Yosemite Server Backup.
Rotation Type | # of Sets | Yearly Sets | Monthly Sets | Weekly Sets | Daily Sets |
---|---|---|---|---|---|
Simple | 4 | 1 full | 1 full | 2 full | |
Simple | 6 | 2 full | 1 full | 3 full | |
Simple | 10 | 3 full | 3 full | 4 incremental | |
Simple | 11 | 3 full | 4 full | 4 incremental | |
Simple | 12 | 4 full | 4 full | 4 incremental | |
Daily Append | N (def. 4) | N full | 4 incremental appends | ||
GFS | 20 | 2 full | 6 full | 6 full | 6 incremental |
GFS | 25 | 2 full | 7 full | 8 full | 8 incremental |
GFS | 30 | 2 full | 8 full | 8 fill | 12 incremental |