Both iCloud and Folder sync don't seem to be working

I just upgraded to Big Sur and did a fresh install. I installed Core Tunnel and restored my premium purchase, made sure Sync was set to iCloud but none of my tunnels restored.

Luckily, I have a bootable backup of my Catalina partition. I booted it and sure enough, it was saying everything was synced. So I made some duplicates of my tunnels from my Catalina install, thinking that might force the sync. I rebooted into Big Sur, but nothing appeared in the tunnel list.

So I exported my tunnels manually from my Catalina install and imported them into my Big Sur install, but I really don't trust that they are actually syncing. I also just now tried switching from iCloud sync to Folder sync. I created a new folder and checked that it said "Last synced: now"... Unfortunately, the folder is empty, so I don't really believe it.

Does sync work?

I confirm the sync works on Big Sur, for some reasons you've to relaunch the app for two or three times to force sync actually work.

I'll investigate this issue even further in next few days.


Hi Yang. Did you find anything when you investigated this? I'm about to need the sync functionality next week and I'm wondering if it will work this time.

Hi Dave, I'm sorry for the inconvenience. We're going to redesign the sync function, before we finished task, following steps may help you get sync back:

  1. Disable Sync
  2. Export all tunnels to a JSON file
  3. Quit Core Tunnel
  4. Delete all files under:
~/Library/Containers/io.coressh.tunnel/Data/Library/Application Support/io.coressh.tunnel
  1. Relaunch Core Tunnel and then import tunnels from the exported JSON file
  2. Reenable Sync

Let me know if you need assistance.

Kindly Regards,


Thanks. I've done this. I'll let you know if it doesn't work.

Hi Yang

Unfortunately this problem continues. I now have duplicate copies of every tunnel configuration.

I'm happy to use whichever sync solution works, is Folder sync any more reliable?


Both Folder and iCloud sync use same solution for sync tasks.

Since you recreated (via importing) all profiles, they are seen as "brand new" profiles in Core Tunnel, so Core Tunnel sync the imported profiles even the remote side has exact same profiles.

This is the expected behavior. Please remove the duplicates, Core Tunnel will sync the removals to remote side, and everything should back to normal.


I can't think that it's expected behaviour really. After following your instructions there were no tunnels installed before I imported them from the JSON file. I imported them re-enabled sync, and there was only one copy.

Then, later, there were two copies. That doesn't seem like it should be expected behaviour.

I think I will just disable sync and manually import/export when I move machines.

iCloud keeps a copy, so even you disabled sync and deleted the local profiles data, iCloud copy would be restored back after you reenabled sync.

Even worse, your other Mac computer see the imported profiles (synced over iCloud) as "brand new" profiles, so ancient copies and newly imported profiles coexist in Core Shell.

We will improve the sync logic in next update.

For now, if you are sure you don't want to keep the ancient copy in iCloud, please follow these steps:

  1. Remove all unwanted profiles in Core Shell
  2. Export all profiles to a JSON file
  3. Disable Sync and remove all profiles in Core Shell on your Mac machines
  4. Delete Core Shell's iCloud data from System Preferences -> Apple ID -> Manage:
  5. Relaunch Core Shell and import the JSON file which exported previously on one of your Mac computers
  6. Re-enable Sync in Core Shell on that Mac computer
  7. Re-enable Sync in Core Shell on other Mac computers