Release Notes

3 Dell PS Series: Space Borrowing for Snapshots and Replicas | TR1084 | version 2
Table of contents
Revisions ............................................................................................................................................................................................... 2
Audience ............................................................................................................................................................................................... 4
Objective .............................................................................................................................................................................................. 4
Introduction.......................................................................................................................................................................................... 4
1 Space borrowing ........................................................................................................................................................................... 5
1.1 Snapshots ........................................................................................................................................................................... 6
1.1.1 Snapshot reserve ................................................................................................................................................................ 6
1.2 Asynchronous replication ................................................................................................................................................... 8
1.2.1 Replication Space ............................................................................................................................................................... 9
2 Best practices for space borrowing ............................................................................................................................................. 10
2.1 Planning space requirements ........................................................................................................................................... 10
2.2 Space borrowing prioritization ......................................................................................................................................... 10
2.3 Space borrowing behavior with changes to storage pools............................................................................................... 10
2.4 Space borrowing for replication ....................................................................................................................................... 10
3 Space borrowing with thin provisioned volumes and SCSI UNMAP ........................................................................................... 12
4 Displaying borrowed space information ..................................................................................................................................... 13
4.1.1 Local Space tab ................................................................................................................................................................. 15
4.1.2 Remote Delegated Space tab ........................................................................................................................................... 18
5 Space borrowing examples ......................................................................................................................................................... 20
5.1.1 Space borrowing with snapshots...................................................................................................................................... 20
5.1.2 Space borrowing with snapshots and replication schedules ............................................................................................ 21
5.1.3 Space borrowing with low delegated space on the secondary group (replication) ......................................................... 23
5.1.4 Space borrowing with low total replica reserve (replication) .......................................................................................... 26
A Additional resources ................................................................................................................................................................... 30
A.1 Related documentation .................................................................................................................................................... 30