Backup the Synology server to a remote Synology server or RSync Server

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This page is currently inactive since November 7, 2009 and is retained for historical/archival reference.
Please look refer to the What is a Backup? article and refer to Network Backup or rsync-compatible servers.


This is a guide on how to use the Synology function Network Backup.
Network backup is a function where one Synology server can backup to another Synology server via the network interface. This function is designed to operate over a LAN or a WAN Network connection and is beneficial for offices that wish to insure that their data is protected by fire, flood, vandalism or some other catastrophic event.
To use this function for Internet use, please forward ports 873, (and 22 for encryption) for the remote Synology product.
Note: This guide will be covering backing up to a Synology Server to another Synology Server.
Backing up/Restoring data from a RSync Compatible Server uses the same procedure as backing up to a Synology Server however it requires different information. For further clarification about what information is different, please look here.

Setting up Network Backup

Step 1:

Begin by logging into the Management menu of the Synology Server


Step 2:

Proceed to the Network Backup menu and perform the following

  • a) Click on Backup
  • b) Click on Network Backup
  • c) Check to "Enable Network Backup Service" if it hasn't been enabled.
  • d) Press "OK" to enable changes
  • e) Click on Network Backup to create a Network Backup job
  • Note: Both the source and destination server must have Network Backup service enabled.

Step 3:

Here is where Network backup jobs will be listed. There is no jobs listed here at the moment. Click "Create" to proceed to a job creation.


Step 4:

Enter the data as following

  • a) Select the source data of what data that needs to be backed up. For this guide, testData1 will be used
  • b) Select the target server type
Synology Server: the target server is a Synology Server
RSync Compatible Server: the target server is a server which has RSync Server Service enabled
  • c) Select the user profile to be used, by default "admin" is used. Use "RSync" for "RSync compatible servers"
  • d) Select the schedule of how often that Network Backup job should occur
Encryption can be used to encrypt the data during transmission and decrypted on the receiving server. This does not encrypt data on the hard drive. (Available on select models)
Select start backup immediately, if the backup must be performed immediately.
  • e) Press "OK" to confirm backup jobs entries (not seen in screen cap)

Step 5:

Here the status of the Network Backup job is displayed. Note the location of here files are stored on the receiving server.


Step 6:

The display result of a Network Backup completed, and is at standby until the next job. Please refer to the Network Backup Log for further information. The network backup log can be found under [Admin Menu] -> [Information] -> [Logs] -> [Network Backup Log]


How to restore data via Network Recovery

Step 1:

From the Network Backup menu, select "Network Recovery Wizard"

NetBackup rest01.jpg

Step 2:

Enter the data in as follows

  • a) Please select either a Synology Server or a RSync Compatible Server
  • b) For this section, please select a server which has been locally detected with the LAN. If the Synology product is located in a remote location, please enter its DNS address or IP address
  • c) Enter the administrative or RSycn password of the remote Server
NetBackup rest02.jpg

Step 3:

Here, conflicts will be listed if the remote server has the same folder structure as the local server

NetBackup rest03.jpg

Step 4:

For the local server, ensure that the data for the local restore folder (testData1) is either empty, or that the data to be restored will replace the content of the local server.

NetBackup rest04.jpg

Step 5:

This screen will be displayed as the Network Restore is in progress. It will return to the the Network Backup menu when the restore has been completed. Please refer to the Network Backup Log for further information. The network backup log can be found under [Admin Menu] -> [Information] -> [Logs] -> [Network Backup Log]

NetBackup rest01.jpg

Backup the Synology Server to a remote RSync Compatible Server

When selecting RSync Compatible Server from the server type, either creating a Network Backup task or performing a Network Recovery the menu will change to show the reflected image on the right hand side. Please fill in the information as follows.

  • Server name or IP Address: Enter the server name or IP address. Using a remote server is possible the necessary ports have been forwarded.
  • Backup Module: The name of the module to use, which is typically found under the "/etc/rsyncd.conf" file on the target server.
  • Username: Enter a user name to use to access the backup folder
  • Password: Enter the password associated for the username
NetBackup Rsync.jpg

After this information has been entered in, continue on with the task that is being executed, with the remaining steps from the above guides.

Backup Procedure Failure & Error Messages

The rsync backup process has a directory & file path name limitation imposed by Linux of 1024 bytes, in windows it is 248 bytes. The synology servers use 58 bytes for the servername_MacAddress path record. Hence the following rules apply to rsync backups:

  1. Any files where the path exceeds 996bytes (=1024-58) will NOT be backed up and the procedure will finish reporting backup failed. It will be reported by email (if configured) and in the Network Backup log.
  2. Any files where the path exceeds 190bytes (=248-58) will be backed up and a warning listed in the Network Backup log. You can check the existence of those files using FTP, but if you browse them by Samba they will be invisible as samba does not support such long file pathnames.

To view the directory&filename path lengths;

  1. Create a file containing all the files names with their full paths, i.e.
    • For Windows - Map a network drive to the Synolgy Server folder containing the data you want to rsync. Open the command prompt (DOS) change to the mapped network drive (e.g. enter the command "m:" for drive m), make sure you are at the root of it (i.e. enter "cd \") and then enter the command "dir /a/s/b > list.txt" which will create a file called list.txt in the root of m:
    • For Linux - Lets assume your errors are when backing up your music folder, enter the command "cd /root" and the use the command "find /volume1/music -name * > /volume1/music/list.txt" to create a file /volume1/music/list.txt. Note: we changed to "/root" because the find command sometimes produces errors if you are not in "/root".
  2. Open the file list.txt in a spreadsheet program (e.g. excel) and use the string length function (LEN in excel) to display the number of characters in each filename path, and then sort the results to find the the longest culprits.


  • With Network Backup the initial backup will always be a full backup, where all content from one server will be replicated to the secondary server. Subsequent backups will be incremental, where only modified data will be replicated to the backup server.
  • Suggested strategy: It's recommended to perform the initial (or full) backup while both servers are within a LAN. Afterwards, move the backup server to the remote location. Once the backup server is online at the remote location, reconfigure the first server to the new IP address of the secondary server, and then incremental backups can take place. This way, it avoids saturating the Internet bandwidth for the initial backup.