Trying to quickly figure out how to copy data between two Synology NAS can include a lot of research and trial and error due to the many ways one can go about doing the task. I found using Shared Folder Sync to be easy and fool proof and provides an exact copy of the data on the receiving NAS.
What is required and how to set Shared Folder Sync up.
Decisions you should make before starting.
How to Set Up Shared Folder Sync
Next Steps - Set Up the Task List
During this part you have options to perform one way sync, two way sync, leave destination file enacted even if the source file were deleted, or delete destination files if source files are deleted.
4/14/2020 7:37 AM
Was very useful ! Thanks a lot !!!
4/28/2020 3:35 PM
My Pleasure - Wrote this article up following my a couple of days figuring out how to copy data between two Synology NAS devices. Thought I would share with others in case they needed to do the same.
5/20/2020 2:49 AM
In your first screen grab is reads "Enable the rsync service to render your DiskStation a backup destination for another Synology server...." but if I read your post correctly, you are advising to do this on the source DiskStation. A bit confusing?
6/13/2020 8:14 AM
Enable RYSNC on the source and destination NAS.
5/28/2020 5:49 AM
Thanks for these instructions! For folks going this route, also take a look at this which offer similar advice: https://www.synology.com/en-global/knowledgebase/DSM/help/DSM/AdminCenter/application_backupserv_sharedfoldersync
6/13/2020 8:19 AM
Thanks for the comments - There are a few other sources on how to keep files either in sync or a duplicate set on another NAS using RSYNC or snapshot replication. There are many scenarios to consider for each.
5/30/2020 11:27 AM
Are these NAS devices both on the same modem?
6/13/2020 8:24 AM
In this situation for illustration purposes, they are located on the same network. However, you can establish a remote RYSNC on a NAS that is geographically located, such as a second office.
6/15/2020 5:24 AM
Thank you for the instructions. What if I only want to backup a subfolder? EG, I want to sync my \\SourceNAS\Video\Movies folder but not the \\SourceNAS\Video\TV folder. Given that the method described applies only at the Shared Folder level, could I create a user that performs the sync task with no permission access to the source TV folder?
6/16/2020 4:06 AM
Shared Folder Sync does not currently support sub-folder selection. If you require granularity for certain sub-folders then you may want to investigate Hyper Backup.
Be advised Hyper Backup is vaulted backups in a database on the destination, meaning you can not simply browse the folder contents in the vault without using the Synology Hyper Backup explorer.
To start using Hyper Backup go to your package center, download Hyper Backup and give it a try.
6/19/2020 3:34 PM
Is it possible to view an ETA when syncing large amounts of data? I'm currently syncing ~11TB to a second NAS and am trying to figure out how long it will take. Both NAS are connected to my network via cat6. TIA
6/22/2020 7:00 AM
By the time you read this reply your 11TB sync should be finished. One way to determine the ETA is by looking at your resource network monitor and doing some math. My NAS has 2 pair of bounded gigabyte connections at around 1500mbs thus would roughly take 17 hours. Here is a link to a calculator - https://downloadtimecalculator.com/