Oracle ZFS Storage Appliance Administration Manual page 527

appliances. Remote replication performs a full update of an entire project and/or share contents,
followed by incremental updates containing only the changes since the previous update.
This topic describes key remote replication (or simply "replication") concepts and replication
terminology.
Remote replication has the following important characteristics:
Snapshot-based asynchronous replication - The replication subsystem takes a snapshot as
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part of each update operation. In the case of an initial update, the entire contents of a project
and/or share are sent. In the case of an incremental update, only the changes since the
last replication snapshot for the same action are sent. Because replication takes snapshots
and then sends them, data is already committed to stable storage before replication even
begins sending it. Continuous replication effectively sends continuous streams of filesystem
changes, but it is still asynchronous with respect to NAS and SAN clients.
Block-level - Each update operation traverses the filesystem at the block level and sends the
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appropriate filesystem data and metadata to the target.
Includes all metadata - The underlying replication stream serializes both user data and
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metadata, including most properties configured on the Shares screen. These properties can
be modified on the target after the first replication update completes, though not all take
effect until the replication connection is severed. For example, this allows sharing over
NFS to a different set of hosts than on the source. For more information, see
Packages" on page 550.
Secure - The replication control protocol used among Oracle ZFS Storage Appliance
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products is secured with Secure Sockets Layer (SSL). Data can optionally be protected
with SSL as well. The Oracle ZFS Storage Appliance can only replicate to or from another
Oracle ZFS Storage Appliance after an initial manual authentication process. For more
information, see "Replication Targets" on page
Encrypted projects and shares - When enabled, transparent data encryption protects
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individual shares (filesystems and LUNs) and projects. For more information, see
Encryption" on page
Protocol independent - The Oracle ZFS Storage Appliance supports both file and block-
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based storage volumes. The replication mechanism is protocol independent.
Compressed replication - Support for compressed replication streams increases
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replication performance and improves throughput utilization between multiple sites
that have limited bandwidth connections. For more information, see
Replication" on page
Replication has the following known limitations:
Actions cannot move between pools
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Network throughput is limited to a maximum of 200 MB/s per project level replication.
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With compressed replication, the effective data rate can exceed the actual physical network
data rate.
559.
549.
Remote Replication Concepts
529.
"Compressed
Remote Replication
"Replication
"Data
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