Administrator Guide

Live Volume overview
44 Dell EMC SC Series: Synchronous Replication and Live Volume | CML1064
Editing a Live Volume with QoS nodes
As a best practice, common QoS Nodes should not be shared between a single SC Series source and
multiple SC Series destinations, particularly where Live Volume managed replications are in use. For
instance, if volume A is replicating to volume B synchronously to support a Live Volume and volume A is also
replicating to volume C asynchronously to support a Live Volume managed replication, an independent QoS
Node should be created and used for each of these replications.
5.5.2 Live Volume
A Live Volume provides additional attributes that control the behavior of the Live Volume and are listed as
follows:
Swap Roles Automatically: When Swap Roles Automatically is selected, the primary Live Volume will be
automatically swapped to the array serving the most I/O load to that Live Volume as long as it meets the
conditions for a swap. The Live Volume logic gathers I/O samples to determine the primary access to the Live
Volume (from either servers accessing it directly on the primary Live Volume array, or servers accessing from
a secondary Live Volume array). Samples are taken every 30 seconds and automated role-swap decisions
are based on the last ten samples (five minutes total). This occurs continuously on the primary Live Volume
array (it does not start once the 30-minute delay timer expires).