Dell EqualLogic PS4100E, Руководство по настройке

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March 2013 Dell EqualLogic Configuration Guide v14.1 12-117
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Snapshot reserve space utilization is a function of the data change rate in the container.
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Old snapshots are deleted to make room for new snapshots if enough snapshot reserve is not
available.
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NDMP based backup automatically creates a snapshot, from which the backup is created.
12.5 NAS Snapshots and Replication
The FS76X0 further ensures business continuity through support for file system, point-in-time
snapshots and snapshot-based, asynchronous replication. It is important to note that Group Manager
block-level replication cannot be used as a data protection strategy for FS76X0 data.
12.5.1 Snapshots
Fluid File System leverages redirect-on-write snapshots that only require one I/O per write operation
and thus avoid the performance degradation of the more traditional copy-on- write approach. Fluid
File System freezes an image and maintains a point-in-time backup of the data. Each individual NAS
container can have its own snapshot policies. The snapshots can be recovered instantly by
administrators and are also available to end-users through the NAS protocols as read-only views.
12.5.2 Replication
The FS76X0 and FS7500 (using FluidFS series firmware 2.0) now support snapshot-based,
asynchronous NAS replication to or from another FS7500 or FS76X0 system in a different EqualLogic
Group at a peer (local or remote) location. An EqualLogic Group containing FS appliances forms a
partnership with another EqualLogic group to replicate data across the two groups.
The NAS replication uses snapshots to replicate only the changed blocks across sites. NAS replication
works at the NAS container level and can be scheduled (hourly, daily, weekly, etc.) per NAS container.
The replication site must have the free capacity in the NAS reserve to replicate the NAS containers
chosen for replication. All NAS container snapshots on the primary are also replicated to the
secondary site.
Note: NAS replication uses the SAN side network to replicate file data. Refer to the NAS
Network Setup Guide for details on making you’re the customer network is ready to
support NAS replication.