Administrator Guide

Synchronous replication use cases
24 Dell EMC SC Series: Synchronous Replication and Live Volume | CML1064
accomplished with Replay Manager (especially recommended for Microsoft products through VSS integration)
or by containerizing volumes by use of consistency groups.
To create consistency across snapshots using consistency groups, a snapshot profile is created with a
snapshot Creation Method of Consistent (Figure 18). This profile is then applied to all volumes containing the
dataset. For virtual machines, the volumes would contain the virtual disks representing the c: drive, d: drive,
or Linux mount points such as / or /tmp. For Microsoft SQL Server database servers, the volumes may
represent system databases, application databases, transaction logs, and tempdb. For Oracle databases, the
dataset must contain all volumes containing any part of the database (data, index, data dictionary, temporary
files, control files, online redo logs, and optionally offline redo logs). For Oracle RAC, OCR files or voting disks
can be added to the dataset. For either database platform, separate volumes for hot dumps, archived redo
logs, or boot from SAN may exist but typically would not need to be included in a consistency group with the
key database files.
Creating a consistency group in Unisphere Central for SC Series
Note: Consistent snapshots may be created for asynchronous and synchronous replications. However,
consistent snapshots are not supported with Live Volumes.
Another method of capturing consistency in snapshots across volumes (and perhaps more useful for
customers with Microsoft Windows, SQL Server, Exchange, Hyper-V, or VMware vSphere) would be to use
Replay Manager. Replay Manager has the underlying storage integration and VSS awareness required to
create application consistent snapshots, across volumes if necessary, which can then be replicated
synchronously (either mode) or asynchronously.
Once data is frozen with consistency across volumes using Replay Manager or consistency groups, those
snapshots will be replicated to the destination volume where they can serve as historical restore points for