Static loop-in fails with DeadlineExceeded: "Loop-in not stored in db, can't update"

[TrezorHannes]

Expected behavior
Follow up from Slack Thread
Copying in @Liongrass and @alexbosworth as a heads-up, that this is a follow-up from our slack-convo.

Static Loop in first try, I'm trying to loop in with one specified UTXO to fixedfloat, with
litloop static in --utxo 15a7deda35cbf2c71b2f0a97709be17d050c195d47eb19ab6624807b50c9c2dd:0 --last_hop 037f990e61acee8a7697966afd29dd88f3b1f8a7b14d625c4f8742bd952003a590 --payment_timeout "90s" --label "static loop in fixedfloat" -v

Actual behavior
It should take the UTXO and loop in with the last hop specified.

To reproduce
When confirming without the --payment_timeout "90s" flag, I get the following error

CONTINUE SWAP? (y/n): y
[loop] rpc error: code = DeadlineExceeded desc = unable to initiate the loop-in with the server: rpc error: code = DeadlineExceeded desc = context deadline exceeded

Logs

025-04-18 18:37:31.680 [INF] SADDR: StaticAddr loop-in 0000000000000000000000000000000000000000000000000000000000000000: Current: InitHtlcTx
2025-04-18 18:37:31.680 [DBG] SADDR: Deposit 15a7deda35cbf2c71b2f0a97709be17d050c195d47eb19ab6624807b50c9c2dd:0: NextState: LoopingIn, PreviousState: Deposited, Event: OnLoopInInitiated
2025-04-18 18:38:01.715 [ERR] FSM: StateMachine error: unable to initiate the loop-in with the server: rpc error: code = DeadlineExceeded desc = context deadline exceeded
2025-04-18 18:38:01.715 [INF] SADDR: StaticAddr loop-in 2b7b3b802e15b815b7af48ed78bdf51d47e77ece9b60eabbb4c9927caa873df2: Current: UnlockDeposits
2025-04-18 18:38:01.715 [ERR] SADDR: Error initiating loop-in swap: unable to initiate the loop-in with the server: rpc error: code = DeadlineExceeded desc = context deadline exceeded
2025-04-18 18:38:01.725 [WRN] SADDR: StaticAddr loop-in 2b7b3b802e15b815b7af48ed78bdf51d47e77ece9b60eabbb4c9927caa873df2: Loop-in not stored in db, can't update
2025-04-18 18:38:01.725 [DBG] SADDR: Deposit 15a7deda35cbf2c71b2f0a97709be17d050c195d47eb19ab6624807b50c9c2dd:0: NextState: Deposited, PreviousState: LoopingIn, Event: OnError
2025-04-18 18:38:01.730 [INF] SADDR: StaticAddr loop-in 2b7b3b802e15b815b7af48ed78bdf51d47e77ece9b60eabbb4c9927caa873df2: Current: Failed
2025-04-18 18:38:01.730 [WRN] SADDR: StaticAddr loop-in 2b7b3b802e15b815b7af48ed78bdf51d47e77ece9b60eabbb4c9927caa873df2: Loop-in not stored in db, can't update

System information
loop version 0.29.0-beta commit=v0.29.0-beta

litcli status
{
    "sub_servers": {
        "accounts": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "faraday": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "lit": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "lnd": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "loop": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "pool": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        },
        "taproot-assets": {
            "disabled": false,
            "running": true,
            "error": "",
            "custom_status": ""
        }
    }
}
{
    "state": "SERVER_ACTIVE"
}

I can't / don't want to rapidely reproduce the error, since the fees from the first try raked up 4x right now, I'd rather wait for a cheaper time window again.

Estimated on-chain fee:                         0 sat
Loop service fee:                           11218 sat
Estimated total fee:                        11218 sat

Conf target:                                    0 block
CLTV expiry delta:                              0 block
Now it's at
Estimated on-chain fee:                         0 sat
Loop service fee:                           42860 sat
Estimated total fee:                        42860 sat
With the same amount of sats. quote in reports the same
Estimated total fee:                        43517 sat

I guess the route loop => last_hop raked up the fees in that one hour, so a cheap hop depleted.

[bhandras]

Hi @TrezorHannes, thanks for reporting this!

The error message might be a bit misleading. What actually happened is that with the given last hop, we couldn't reach you, so the service fee defaulted to a generic rate (which is usually just the routing fee + 1 sat).

[TrezorHannes]

Thanks @bhandras , so just to confirm: your hypothesis is, that the loop in route

• couldn't reach me due to a time-out
• or to a liquidity bottleneck

whereby my question to the former would be, is this mitigatable with the --payment_timeout "90s"
and wrt the latter, couldn't we get more verbose with the error messaging?