I’ve had Synology devices for years, and always transferred the disks from one NAS device to another. That caused that I haven’t been able to use the btrfs file system with all its benefits and was still on ext4.

During my latest disk expansion I’ve created another volume so that I have two volumes, /volume1, which consists of 90% of the space of my disk pool, and /volume2 for the other 10%.

I’m now in the process of making a full backup of Volume 1, so that I can delete it, and then create a btrfs volume instead. As I can’t delete all packages, I’ve looked up how to move packages between volumes.

This site gave me some nice hints, but I found out it wasn’t yet enough. So I’ll share my experiences here.

All Synology packages are having a folder inside /var/packages. That’s useful. By for example checking through

ls -aRl /var/packges | grep volume1

you can check if there are still packages on volume1.

Packages also have folders on the volumes, mostly in /volume1/@app* folders. So there’s @appstore, @appconf, @apphome, @appdata and @apptemp. Symlinks to the corresponding folders are inside the /var/packages folder. So that means that most of the actual package data is stored on the volumes itself, whereas the /var/packages folder only contains the administration of which packages exist and which folders they use.

In case of, for example, package HyperBackup, I didn’t want it to be uninstalled. I’d rather keep it available, as you might understand. To move it to the other volume anyways, I’ve executed the following steps:

1. Stop the package in DSM in the package manager. Don’t uninstall it, but stop it.

2. Close the package manager window in DSM, else it’ll start complaining

3. Go in an SSH shell to /var/packages/<packagename>, so in this case cd /var/packages/HyperBackup

4. Execute the following:

   mv "/volume1/@appconf/HyperBackup" "/volume2/@appconf/" && \
   mv "/volume1/@apphome/HyperBackup" "/volume2/@apphome/" && \
   mv "/volume1/@appstore/HyperBackup" "/volume2/@appstore/" && \
   mv "/volume1/@apptemp/HyperBackup" "/volume2/@apptemp/" && \
   mv "/volume1/@appdata/HyperBackup" "/volume2/@appdata/" && \
   rm etc home target tmp var && \
   ln -s "/volume2/@appconf/HyperBackup" etc && \
   ln -s "/volume2/@apphome/HyperBackup" home && \
   ln -s "/volume2/@appstore/HyperBackup" target && \
   ln -s "/volume2/@apptemp/HyperBackup" tmp && \
   ln -s "/volume2/@appdata/HyperBackup" var
   

5. Re-open to the package manager in DSM and go to the package

6. See that the package is now on Volume 2.

7. Start the package

Some packages may have some more issues and may need to be repaired in the package manager. If you executed the above code, a repair will be easy.

In case of the Docker package, I found that it also created a symlink to /volume1/@docker somewhere in the @appdata folder I believe. You’ll want to update that manually as well.

Good luck!