Release Notes for Snapshot Replication

Fixed Issues

1. Fixed an issue where replicated shared folders on destination servers couldn't update properly when the system misidentified an ongoing Hyper Backup task.

What's New

1. Supports configuring the number of concurrent tasks on certain models to better allocate system resources. (Learn more)

Fixed Issues

1. Fixed an issue where the "Replication in progress" status was continuously displayed after replication tasks were stopped.
2. Fixed an issue where users might be unexpectedly signed out from DSM when editing replication tasks.
3. Fixed an issue where shared folders' snapshots were kept when users only chose to reserve LUN snapshots and snapshot settings during package uninstallation.
4. Fixed an issue where replication tasks might fail when the "Replicate schedule local snapshots" option was enabled.

Fixed Issues

1. Fixed an issue where the system might fail to take snapshots when the description of snapshot tasks exceeded the length limit.
2. Fixed an issue where the size of the initial copy might not be updated during the replication task creation.
3. Modified the sorting of the destination volume during the replication task creation.

Compatibility and Installation

1. Updated to be compatible with DSM 7.0.

What's New

1. Enhanced the usability of snapshot retention policy setup and added an option of specifying the days to retain all snapshots.

Fixed issues

1. Fixed an issue where replication tasks could not execute if their previous tasks failed.
2. Minor bug fixes.

What's New

1. Users can now customize when to transfer snapshots to the destination server to reduce the performance impact of replication tasks.
2. Added support for replicating local scheduled snapshots to the destination server along with replication tasks. (Requires DSM 6.2.3.)

Fixed Issues

1. Fixed an issue where replicating shared folder snapshots to a local volume might fail.
2. Minor bug fixes.

1. Fixed an issue where upgrading to 7.1.0-0445 may cause replication plans which had been created in 6.1.2-0173 or earlier versions to fail.

What's new

1. Added support for retention policy trigger time (available on DSM 6.2.2 or above).
2. Added support for two-step verification for replication tasks.
3. Added support for local replication tasks for iSCSI LUN.

Fixed issues

1. Fixed an issue where taking snapshots may fail when other applications take snapshots at the same time with the same snapshot file name.
2. Fixed an issue where calculating unsynchronized snapshot file size may fail.
3. Aligned display date and time formats with DSM.
4. Minor bug fixes.

What's New for DSM 6.2

1. Introduces Advanced LUN, a Btrfs-based LUN type that creates and restores snapshots in seconds.
2. Added the snapshot calculator to provide a graphical representation of storage consumption by snapshots in a given period of time.
3. Encrypted shared folders now support clone and test failover.

Updated the maximum number of replication tasks

XS/XS Plus series

• Maximum number of shared folder replication tasks: 64
• Maximum number of iSCSI LUN replication tasks: 32
• Maximum total number of replication tasks: 64

Plus series

• Maximum number of shared folder replication tasks: 32
• Maximum number of iSCSI LUN replication tasks: 16
• Maximum total number of replication tasks: 32

Value series

• Maximum number of shared folder replication tasks: 16
• Maximum number of iSCSI LUN replication tasks: 8
• Maximum total number of replication tasks: 16

Improvements & Fixed issues

1. Increased replication speed when the tasks involve transmitting a large number of small files.
2. Enhanced usability by adjusting setup procedure and troubleshooting messages.
3. Fixed an issue where snapshots could not be deleted when the volume was full.
4. Fixed an issue where local replication might fail after the destination shared folder was renamed.
5. Fixed an issue where the system might fail to run multiple replication tasks at the same time.
6. Thai user interface is now available.

Limitation

1. Starting from DSM 6.2, the core replication function is centrally managed by a new package, Replication Service. Packages with replication feature, such as Snapshot Replication, must install Replication Service package.

1. Enhanced replication stability when multiple replication tasks are running at the same time.
2. Enhanced the connection between the source and remote servers when both are connected via VPN.
3. Fixed an issue where replication could not be resumed after an abnormal shutdown.
4. Fixed an issue where the replication progress was not accurate under certain circumstances.

1. Fixed an issue where replication could not be properly terminated.

1. Supports replicating "homes" shared folder to remote server.
2. Fixed an issue where replication could not be properly terminated.

1. Thanks to the extended coverage of Btrfs file system, more models will benefit from the advanced data protection of Snapshot Replication.
2. Better protection for encrypted shared folders. You can now replicate the taken snapshots of encrypted shared folders for a more complete protection.
3. In addition to a remote destination server, snapshots can now be replicated to a local volume, providing greater flexibility with more copies stored.
4. Pause/resume is now supported to save time and bandwidth when the connection quality is poor.

1. Improved CPU usage after running of a replication task for shared folder.
2. Fixed an issue where the shared folder on the original destination server may remain read-only after the deletion of replication task.
3. Enhanced the user experience for cleanup of test failover.
4. Fixed an issue where the user interface may fail to display properly under certain circumstances.

1. Added support for creating a replication task towards Snapshot Replication 6.0-0034.
2. Added support to act as destination server of a replication task from Snapshot Replication 6.0-0034.
3. Snapshots can now be named after the time of user's local time zone.
4. Optimized the CPU utilization.
5. Moved the "Make snapshot visible" option from Control Panel to Snapshot Replication.
6. Improved the stability of shared folder replication.
7. Improved the stability of large iSCSI LUN replication.

1. Added support for creating a replication task towards Snapshot Replication 6.0.1.
2. Added support to act as destination server of a replication task from Snapshot Replication 6.0.1 (Replication of the shared folder [photo] is supported only when the Photo Station package on the source server is upgraded to 6.5.0 and above).

1. Snapshot Replication is now a stand-alone package. It is previously named as Snapshot & Replication in DSM 6.0 Beta and Data Protection Manager in DSM 5.2.
2. Shared Folder Snapshot
   • Take a snapshot of shared folders up to every 5 minutes.
   • View snapshot data in all file services or File Station, or by clicking the Previous Versions tab in the Properties dialogue box in File Explorer on Windows PC.
   • Increase the maximum snapshot versions of a shared folder to 1024 for all currently available models (except for DS216+ on which the number is limited to 256).
   • Limit the maximum snapshot versions of all the shared folders to 65536 for all currently available models (except for DS216+ on which the number is limited to 4096).
   • Supports shared folders located on Btrfs volumes.
3. Shared Folder & LUN Replication
   • Replicate your data in shared folders and iSCSI LUNs from one server to another by taking and sending a snapshot to the remote server.
   • Extend a replication by replicating data from a destination server to another secondary destination server to make multiple copies of your data.
   • Replicate one shared folder or iSCSI LUN to up to 3 destination servers from the same source server.
   • Limit the maximum number of replication tasks to 64.
   • Statistics of transferred size and sync duration are recorded and displayed as a report.
   • Allows administrator users to export the replicated data to external devices, and then deliver and import it to the recovery site, reducing bandwidth usage in your production environment.
   • Provides an overview topology to show how your replicas are stored.
   • Supports port forwarding by customizing address and port of a replication task.
   • Now you can encrypt replication transmission.
   • iSCSI LUN replication can be managed via Synology Snapshot Replication or VMware vCenter Site Recovery Manager. (Installing Synology SRA on VMware Site Recovery Manager servers is required.)
   • Only Advanced iSCSI LUNs and shared folders on Btrfs volumes are supported.
4. Recovery
   • You can perform a failover on shared folders or iSCSI LUNs by making the replicas on the destination server writable when the source server is not healthy.
   • You can perform a test failover to make a clone and run all necessary tests in the event of disaster.
   • You can perform a force failover when the source server is healthy.
   • After performing a failover, you can perform a re-protect action to sync data on two servers again.
   • When performing a re-protect action, you can choose either of the servers to sync data from and choose the new source server for the replication task.