I've been running an Umbrel with many LN channels for over 2 years now. The only issue I've encountered was when I installed too many apps from the Umbrel App Store, then the LND started misbehaving and my node was going offline regularly. I uninstalled most of the apps and had no issues since.

The on-chain wallet which is associated with your Lightning node must be online in order for LN to work. So as far as I know, you cannot connect a HW wallet to any LN node's on-chain wallet, Umbrel or not.

You should think about such an on-chain wallet as part of Lightning, not as a standard Bitcoin wallet. Umbrel did a great job changing the UI so that users do not feel like they are getting a standard BTC wallet with their LND (Lightning implementation that is default on Umbrel). [If you are interested what exactly: Both Lightning and on-chain balances are in the "Lightning" app, and with the On-Chain you have buttons called "Deposit" and "Withdrawn", not "Receive" or "Send"].

If you want to connect a cold storage to your Umbrel, what you can do is to create a separate wallet though an app you can install on Umbrel like Spectre Desktop and connect Trezor/Ledger to that. This is the recommended way when you are using something like BTCPay server to accept on-chain transactions using Umbrel.

Anyway, overall, I've had a great experience with Umbrel so far.

That being said, I know that some people who are experts in BTC security have concerns about Umbrel in general – I have yet to discover what are those concerns and if they are based.

Do you also stay inside your home because outside you can get killed?

For what it's worth they've been making steady progress on SECURITY.md even though some really big ticket items, like TLS support, remain.

There are some small things you can do like backup your channels and enable 2FA on your Umbrel, but it'll never be as secure as cold storage bitcoin.

Just don’t put more BTC into your channels than you are willing to lose. That amount will be different for everyone depending on risk tolerance. Start small and learn.

Having said that, I am running a LN node on Umbrel and haven’t had any problems or lost any funds. There’s a good community of support, both on Umbrel forum and here.

Have over two years umbrel node. Opened several channels with it. Never encountered issues. No concern at all. If you know what to do in case of crash there is little to worry about. Worse thing that can happen is you have to start over again with all your channels because a restore forces all your channels to close and those fees are lost. Opening again cost you fees but overall no much sats are lost

How else do you open a LN channel without hot keys? Having burned myself opening channels in the past, only way to get comfortable with it is to keep your sat exposure to something you won't feel painful about losing

I’m also interested in this. Thanks for asking, I hope you get some useful answers!

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