SyncMirror is a technology that allows you to mirror information by creating two absolutely identical copies of data recorded on different media inside the storage. This ensures the maximum possible continuous customer service workflow and shows the highest level of protection in case of system failure.
SyncMirror can function in two modes:
- Local SyncMirror.
- MetroCluster SyncMirror (MC-Configuration SyncMirror).
Data storage systems
And the difference between SyncMirror MCC and SyncMirror is that in the case of SyncMirror, information from the NVRAM of one controller is constantly mirrored to two copies of data in the partner controller of the HA pair. This approach is often used to protect the system from losing an entire shelf due to some kind of failure.
In the case of SyncMirror MCC, NVRAM mirroring is performed simultaneously between several controllers: inside the pair and on the controllers of the response site. This solution is implemented using special FC-VI ports.
Features
SyncMirror can perform replication almost at the RAID level, and the most appropriate analogy that can be drawn here is RAID-60:
- there are two plexes (“sub-mirrors”) — Plex0 and Plex1;
- each Plex can have several RAID-DP groups.
This analogy is valid because the pair of Plex described above are defined as composite, mirror parts of the same system. But in reality, in a stable system, mirroring occurs on the controller, NVRAM-level.
The key detail of SyncMirror is the need for full—dimensional symmetry of drives in a pair of journaled pools. Symmetry should be expressed in the same type, speed, volume, and RAID groups.
Replication synchronization solves 2 problems:
- On the one hand, it allows you to take the load off the disk subsystem, because it replicates only the memory itself.
- On the other hand, to get rid of consistency and Split-Brain problems, you need to be sure that the information was recorded on a remote system.
As a result, this synchronicity, regardless of the type of data storage system, allows you to reduce the response time and the time to send information to a remote resource.
Maximum seamless management
Managing copies of data in SyncMirror is performed according to the same instructions as in the case of managing any other data in the storage. In addition to ensuring high availability of information using SyncMirror, you can break the connection between synchronized pairs of copies of datasets with just one command, so that these copies can then be used by other applications in read-write mode.
This solution can be called almost ideal to avoid the typical backup problems. Because background processes can work using mirrored information without interfering with the structure of the work environment. As a result, a significant increase in productivity is achieved.