Directory/File Or Cartridge Based Replication - Quantum DXi8500 User Manual

Directory/File or
Cartridge Based
Replication
Quantum DXi8500 User's Guide
Caution: A saved snapshot is necessary to recover your data at a
later time. For this reason, it is not enough to simply enable
replication for a share or partition. You must also configure
a replication schedule (recommended) or perform manual
replication on a regular basis to send snapshots of the
share or partition to the target system.
If the source system ever becomes unavailable, you can recover the
share or partition on the target system using a saved snapshot. After
you recover a share or partition, it is recreated on the target system and
is available for use. Once the source system becomes available again,
you can perform a failback operation to restore the share or partition to
its original location.
Like replication, Directory/File or Cartridge Based Replication sends data
from a NAS share or VTL partition to another system where it can be
accessed. However, Directory/File or Cartridge Based Replication differs
in a number of important ways:
• Both replication and Directory/File or Cartridge Based Replication
must be enabled for the share or partition.
• A unique Sync ID is used to associate the replicated share or
partition on the source system with the share or partition that will
receive the replicated data on the target system.
• You do not need to schedule or manually perform Directory/File or
Cartridge Based Replication through the remote management
console. Instead, replication is triggered when a file is closed or a
period of time after it is modified (NAS shares), or when a tape
cartridge is unmounted (VTL partitions).
Note: For CIFS shares, a file is replicated immediately after it is
closed. For NFS shares, a file is replicated after it has been
idle (not accessed) for several minutes.
• After directories and files or cartridges are replicated using
Directory/File or Cartridge Based Replication, they are automatically
recovered on the target system and are immediately available for
use. There is no need to first recover the share or partition to access
its data.
Chapter 6: DXi8500 Replication
Understanding Data Replication
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