lnd: Payment stuck in IN_FLIGHT state

Background

Creating as a replacement for this ticket.

We have a payment that is stuck in the IN_FLIGHT state. One of the htlcs is stuck in the IN_FLIGHT state despite having an expiry that is in the past. When listing channels we see no pending htlcs for the involved channel.

Your environment

version of lnd: 0.11.1-beta commit=v0.11.1-beta
which operating system (uname -a on *Nix): Linux nodes-lnd-667ff844cc-2krmj 4.19.112+ #1 SMP Fri Sep 4 12:00:04 PDT 2020 x86_64 Linux
version of btcd, bitcoind, or other backend: bitcoind 0.17.1
any other relevant environment details

Steps to reproduce

Initiate an outgoing payment (loop operation in our case). Get unlucky, and get one of the htlcs to get stuck in the IN_FLIGHT state beyond the expiry of the htlc.

Expected behaviour

Payment should FAIL when expiry of htlcs is breached.

Actual behaviour

Payment gets stuck in the IN_FLIGHT state after expiry of htlcs. In addition, channel shows no pending htlcs (in fact our node shows 0 pending htlcs).

Example payment

About this issue

Original URL
State: closed
Created 4 years ago
Reactions: 1
Comments: 26 (15 by maintainers)

Most upvoted comments

Hey, thanks for explaining here. IIUC, it seems like we have a terminal error = no more shards sent, but still wait on any existing IN_FLIGHT shards type approach? If a payment ends up with a stuck shard, as is the case here, we will just end up waiting till CLTV expiry notification (I assume from the Switch). At this point we will be able to consider the shard failed and report the payment as failed to the user so they can retry.

I fully agree with your summary, @carlaKC.

I have a local branch for user initiated payment “cancellation” via RPC. I might have some questions soon for you on that @halseth, though it was surely helped by understanding this better.

calvinrzachman on Apr 19, 2021

Going to pick this one up!

carlaKC on Apr 14, 2021

@lukaszsamson Do you still have the full logs around when this happened? Would be very helpful if I could take a look at them. Feel free to reach out to me on keybase (@halseth) or the LND slack (@johanth)

halseth on Mar 22, 2021