Snap Assisted Replication Of Nas Volumes - American Megatrends StorTrends 1300 User Manual

Snap assisted replication of NAS volumes

Snap assisted replication is also supported on top of NAS volumes. The NAS snap
scheduler should be used to take consistent snaps for NAS volumes. Replication will be
done only on consistent snapshots taken using the scheduler. Unlike SAN volumes, NAS
volume replication requires additional configuration replication to secondary system.
This configuration includes, share configuration and user database. Share configuration
replication is handled by periodically transferring the shares in the primary system to the
secondary whenever a snapshot replication is done. However, the share configuration
replicated will be the configuration that is available during the time of replication and not
the one at the time the snap was created in the primary system. In the secondary system,
this configuration will be maintained in a temporary location. When the next snapshot is
replicated, it will be overwritten with the new configuration from the primary system.
This temporary share configuration will be merged with the original configuration during
a Failover.
The User database is handled in a different way. If ADS / NIS users are used in the
primary system, then administrator is requested to configure the secondary system also
with the same ADS / NIS configurations. This will ensure that, in the event of a failover,
the secondary system will provide the same access permissions for the ADS / NIS users
as mentioned by the configured ACLs. Alternately, if local users are used, then it is the
responsibility of the administrator to create same users / groups – with same UID / GID
in both the systems. However, usage of ADS / NIS for user / groups is recommended. For
simplicity and easy manageability, only one-one configuration is supported for NAS
volume replication. For example, one or many NAS volumes from primary system (A)
can be replicated to similar volumes in secondary system (B). The secondary system (B)
cannot participate with any other primary / secondary for NAS replication. However,
both systems (A) & (B) can have independent volumes that are not replicated.
244 StorTrends® 1300 User's Guide (StorTrends iTX version 2.7)