Release Notes
23 Dell PS Series: Space Borrowing for Snapshots and Replicas | TR1084 | version 2
5.1.3 Space borrowing with low delegated space on the secondary group (replication)
Remote replicas can borrow beyond their total replica reserve, but the total amount of configured reserve space
must still fit within the delegated space.
In this example, a new 100 GB thick volume on the primary group is configured for replication with the default total
replica reserve, 200%. This means that 100% is dedicated to the current replica volume reserve, and the remaining
100% is reserved for additional replicas in the total replica reserve.
When replication is enabled on this volume, a 100 GB thin-provisioned replica volume is created on the secondary
group, even though the primary volume is thick. This is typical behavior when enabling volume replication. As the 100
GB replica volume is thin-provisioned, 10% of the replica volume will be reserved by default for thin provisioning. This
yields a 10 GB current replica volume reserve (10% of 100 GB).
Total replica reserve is a percentage of current replica volume reserve. As the total replica reserve is 200%, and the
current replica volume reserve is 10 GB, 200% of 10 GB results in a 20 GB total replica reserve. 100% of the 10 GB (10
GB) are in use in the current replica volume reserve, and a remaining 100% of the 10 GB (10 GB) is available for
additional replicas in the total replica reserve.