Unable to initiate a swap

[kornpow]

Environment:

LND 0.18.3-beta commit=v0.18.3-beta
LOOP 0.28.7-beta commit=v0.28.7-beta

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I get the following error, whether I use a --channels flag or not. Also note, this pasted error is for 4M sats, but I have tried it with small values like 2M sats, and larger values like 25M sats.

Loop CLI Error message

[loop] rpc error: code = Unknown desc = channel balance too low for loop out amount: Requested swap amount of 4000000 sats along with the maximum routing fee of 80010 sats is more than what can be routed given current state of the channel set

The logs are configured in trace mode, but either way there isn't much to see here. The loop out request never actually initiates a loop out.

2024-10-12 11:41:34.520 [INF] LOOP: Offchain swap destination: {redacted}
2024-10-12 11:41:37.514 [INF] LOOPD: Loop out request received
2024-10-12 11:43:02.745 [INF] LOOP: Offchain swap destination: {redacted}
2024-10-12 11:43:04.243 [INF] LOOPD: Loop out request received
2024-10-12 11:43:19.190 [INF] LOOP: Offchain swap destination: {redacted}
2024-10-12 11:43:20.634 [INF] LOOPD: Loop out request received
2024-10-12 11:44:45.298 [INF] LOOP: Offchain swap destination: {redacted}
2024-10-12 11:44:47.557 [INF] LOOPD: Loop out request received

Let me know if I can provide further information, LND logs (please let me know what subsystem to focus on), etc.

[hieblmi]

Thanks for raising the issue @kornpow!

The error seems to come from a validation function prior to swap execution.

Would you mind helping us investigate this by running a loop version with extended trace logs: #832?

[kornpow]

@hieblmi Thanks for making this log level PR. These are my results.

Command:

loop - out --amt 10000000

2024-10-14 21:36:44.111 [INF] LOOP: Offchain swap destination: {redacted]
2024-10-14 21:36:46.210 [INF] LOOPD: Loop out request received
2024-10-14 21:36:46.227 [TRC] LOOPD: Checking if 0.10200010 BTC sats can be routed with 5 parts over channel set of length 1
2024-10-14 21:36:46.227 [TRC] LOOPD: Channel 914492408312299520: local=0.02218873 BTC remote=0.02773597 BTC
2024-10-14 21:36:46.227 [TRC] LOOPD: Total bandwidth: 0.02218873 BTC

It is interesting that the channel set is of length 1, and it is also VERY interesting the channel it happens to be attempting to use. The channel it is trying to use is the oldest channel on my node. It is also the only channel which showed up on terminal.lightning.engineering for the longest time.

[hieblmi]

Indeed interesting, the channel set of length 1 suggests that you only have one active channel on your node.
Is lncli listchannels | grep '"active": *true,' | wc -l greater than one on the system?

[kornpow]

Im sorry, but this is my fault. I have 3 nodes running on this machine and I fumbled some ports.