BlueWallet & Umbrel

Hi, I opened a lightning channel on my a get umbrel node. How can I import my LND wallet into BlueWallet? I want to pay from my mobile BlueWallet app and spend sats on my lightning wallet on my Umbrel full node.

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It is a bit different the way BlueWallet works with your node. It uses your node’s liquidity, but you have to “fund” the lightning wallet on-chain. When you fund your LN wallet in BlueWallet, it moves that bitcoin to your node’s Bitcoin wallet and gives you funds you can now spend on LN. This was done to enable multiple people (like friends and/or family) to connect to one node, but only spend the funds they themselves contribute. The BlueWallet LNDHub keeps track of the balances for each connected wallet, but your actual node doesn’t know anything about it. Hope that makes sense.

If you want to use your node’s liquidity directly, try using Zap.

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Thx bro i try ZAP :zap:

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Hi,

I don’t quite understand that answer. I am new here too. I enabled the Bluewallet app on my Umbrel node. I created a lightning wallet on Bluewallet and connected it to the QR code in my umbrel to link the two up. When I go to fund the Lightning wallet on Blue wallet, it only gives me the option to use the on-chain BTC wallet in Blue wallet to fund it. If I open a channel in Umbrel, will that fix it so that it uses funds in my on-chain BTC wallet in Umbrel to refill the lightning wallet in blue wallet?

Also, I installed Zap (Android) and in umbrel there was no app for Zap. So I am not sure how one is to link Zap to Umbrel.

Sorry to be a pain. I am not a Luddite but I find this lightning business quite confounding.

BlueWallet can only use Bitcoins for on-chain payments after entering a seed on your app. Bitcoins locked in the LND channel on your node cannot be ingested by the BlueWallet app. To work with off-chain payment, I use Zap. The Zap app allows me to ingest lightning network liquidity from my mobile on my node Bitcoins.

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How did you connect ZAP to Umbrel? There isn’t an app in the app store like there is for Blue Wallet.

Umbrel -> Connect Wallet -> Zap (Android/iOS/Desktop) -> follow the instructions.

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Done. Thank you. I had been looking for an app in the App Store rather than the more obvious “Connect wallet” hiding in plain sight.

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Like I mentioned above, BlueWallet is designed to work for multiple people with a single node in the way that each person can only spend the Bitcoin they contribute. With this in mind, here’s how it works, more or less.

The app on your Umberl LNDHub is basically a “master wallet” that can use whatever channels you open on your LN node to send/receive payments. Then once you connect the BlueWallet app on your mobile to LNDhub, LNDhub creates an account for that particular connection. Then you can have your Dad and your Mom do the same. Maybe even a couple friends. So each mobile wallet starts with a balance of zero because otherwise anyone can spend all your money. Then each user has to fund their own account, and this can only be done on-chain. Whatever funds each user adds can then be spent using the funds on your node. LNDhub keeps track of all balances, but your node just sees a single wallet - LNDhub.

When one of these mobile accounts is funded, the Bitcoin is simply transferred to your node’s Bitcoin wallet, thus even though you let others use your node, they only spend their own funds.

The BlueWallet is really nice, and I do recommend you try and get it working, it’s easier than you think.

Here’s a solid LN tutorial using Umbrel

Great explanation. However, I still have some questions. What happens if, for instance, and just to simplify, I have 2 channels in my Umbrel lightning node: one with incoming capacity of 100k sats and one with outgoing capacity of 100k sats. And then I have two “users” connected from their BlueWallet apps, and each funds their wallet with 1M sats.

How many sats can each send and receive from their BlueWallet App? Am I right to assume they can only send and receive 100k sats, since that is the capacity available in my Umbrel node?

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The honest answer is: I don’t know. I haven’t tested this case personally.

Basically your question is what happens if users have more funds in their wallets than you have outbound liquidity on your node. I surely think the programmers accounted for this. This could occur for multiple reasons, such as users funding more than the node has, the node operator (or remote node operator) closes one or more channels, the node operator spends most of the liquidity outside BlueWallet and so on. If I was the programmer, I would likely allow users to have more on their balances than is available to spend. Then the outbound liquidity would be utilized on the first-come-first-served basis, and once the liquidity runs out, the user would just get an error saying that there is insufficient liquidity to make payment. But this is just a thought experiment, if anyone knows different please let me know.

As the designated family node operator, it would be up to you to ensure sufficient liquidity. Remember that when other users fund their accounts, that Bitcoin goes into your node’s BTC wallet. When you see Bitcoin show up in your wallet, you should either loop-in the funds into existing channels or open new ones.

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I wonder if there are any plans to allow people to fund their LNDhub account with lightning transactions because it kinda defeats the purpose if people have to fund it with an on-chain transaction since they may as well just use Phoenix app and get their own channel then

Come to think of it i was testing bluewallet today and i was able to fund the wallet with a lightning transaction. So i wonder how that was possible. Afaik it uses BlueWallets LNDhub by default

I think they wouldn’t be able to fund their lndhub wallets because you don’t have enough incoming capacity to receive those 1M transaction.

Edit: looking into it, it seems like they can fund their wallets with a on chain transaction. But I guess they will get no route errors and can’t use that balance until you open some more channels for the hub.

My understanding on how LNDhub/Bluewallet lightning works is, it borrows your node’s liquidity (channels).

Your BlueWallet is funded with a lighting invoice to the hub, your wallet gets credited with sats. When then you send transactions out, it’s via the hub again and your balance deducted. It’s custodial as the lightning funds are in the hub’s channels.

This thread is great and has answered so many questions. I second the recommendation above - the BTC sessions video is very informative.

My question is regarding the concept of being the banker for trusted family and friends. I have personally tested the scenario where I allow my Umbrel node to have insufficient channel liquidity to support the attached Blue LN wallet. The Blue wallet gets a message that the payment failed because there aren’t enough sats on the channels.

So the question is: Is there a way in the Blue wallet LND app to see what the node operator’s commitment is to the wallet holders? I know what is on my Blue LN wallet but I am the customer AND the banker in that case. If a family member attaches to my node, I can’t see the balance on their Blue wallet from the node. I would have to ask them what their balance is. Hopefully it is there somewhere on the node and I just haven’t found it.

I’m on board with the responsibility that comes with being the banker, but I need to know the magnitude of that responsibility.

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