Restoring Old Core Lightning (CLN) Node

My CLN app was recently not working so I uninstalled the app. Upon reinstalling it, it doesn’t seem that I’m able to import the old node, and a new one was created. Does anyone have an easy way to upload the old node? Thanks!

I tried to reproduce this on my side by running umbrelOS in Docker (since I don’t have an umbrel yet) and installing the Core Lighning app, but in that Docker setup the apps themselves wouldn’t install properly, so I couldn’t fully mirror your exact scenario. Still, I did some digging through the Core lightning docs and also bounced ideas off an AI assistant to understand what might be causing this issue.

From what I’ve gathered, uninstalling ans reinstalling the CLN app on Umbrel will normally create a fresh node with its own hsm_secretand database. If your previous CLN data directory (with the old hsm_secret and lightning DB) is still somewhere on your Umbrel disk, there’s a good chance you can point the app back to it and get the old node back. If that directory really is gone, I think restoring the exact old node state becomes difficult..

If you’re up for it, one avenue you could explore is SSH’ing into your Umbrel box and checking under ~/umbrel/app-data/ to see whether there’s any Core Lightning app directory that might still hold data from your previous node (it’s not guaranteed to be there; it depends on how Umbrel handled the uninstall). If you do happen to find what looks like an older CLN data folder, you might carefully try stopping the app, making a backup copy of that folder somewhere safe, and then testing whether pointing the CLN app at that older data directory brings back the old node state. I wasn’t able to fully verify this in my Docker test environment, so please treat this as a hypothesis rather than a guaranteed procedure. :slightly_smiling_face:

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One more potentially useful resource: there’s an older community forum thread that walks through a more “fool‑proof” Core Lightning backup/restore approach on a new machine: Fool-proof Core Lightning Backup and Restore to a new machine?

It doesn’t describe this exact uninstall/reinstall situation, but the discussion around what needs to be backed up and how to think about CLN recovery might help you both now and for future backups.

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Afaik Umbrel handles this badly (it erases app data during ln instance uninstallation, countless bitcoins were burned over the years because of this if people acting first and researching / thinking later).

  1. were any funds / channels involved?

  2. have you progressed with the recovery since then and if not what old cln node data you have? I assume you backed something up before the uninstall, right?.. (hsm_secret at the very least, if ur very lucky, dont have any zombie channels and can figure unclosed channelpoints, everything can be recovered only with hsm_secret)

I have decent skill disaster-recovering from LND and CLN (although not necessarily in umbrel environment), lmk if u need help.

Thanks for reaching out everyone.

I need to check to see what I have backed up. Not sure entirely. Was using CLN for BOLT12 payments from OCEAN. Channels were not too big, hoping to recover it. Will take look at exactly what I have save.

Will report back. Appreciate it everyone!

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