Recovery of unilateral close with too low fee

Back in June a channel closed with a fee near 1sat/byte. It is looking doubtful that this will ever confirm and I am likely not the only one.

The message on the state update is : "Offered HTLC 4 RCVD_ADD_REVOCATION cltv 792627 hit deadline" and there are several htlcs in the listpeerchannels output. The address is not listed in dev-listaddrs.

The ability to CPFP redeploy / withdraw these funds with minconf=0 would be ideal.

Otherwise, advice / clues on how to safely get these funds back into channels would be much appreciated.

[Donach]

Having same issue, now for over 2 months with <5 sat/vB - though the chance is more likely to get confirmed, even in the last few months, we've never went below 6 sat/vB...
I've tried to create a tx using the UTXO from the channel close, but the wallet, even though it lists the UTXO using "listtransactions" and then checking with "getutxout", when I try to use that UTXO for withdrawal/tx creation, it tells me it doesn't know such UTXO...
Much appreciated, will tip the dev who makes this possible, rather than paying exorbitant fee to pool for acceleration...

[Donach]

This seems to be related to #6268

[har15eld0n]

Having the same issue here. Channel was cooperatively closed more than a month ago at a 2.45 sat/vB fee, just before the fee explosion, and is now stuck (and actually disappeared from 300MB standard sized mempools)

It is not a big enough amount to justify a miner transaction acceleration (like I did when it happened to me once, in the exact same conditions)

I imported the wallet in sparrow using the hsm_secret converted to an XPRV but I don't see the closing transaction...

What is the usual procedure for this use case? funds are lost forever?

[Donach]

Having the same issue here. Channel was cooperatively closed more than a month ago at a 2.45 sat/vB fee, just before the fee explosion, and is now stuck (and actually disappeared from 300MB standard sized mempools)

It is not a big enough amount to justify a miner transaction acceleration (like I did when it happened to me once, in the exact same conditions)

I imported the wallet in sparrow using the hsm_secret converted to an XPRV but I don't see the closing transaction...

What is the usual procedure for this use case? funds are lost forever?

For me I waited it out and it eventually confirmed.
What you can try is to install Zeus and connect to your CLN node, and there I have button to speedup channel open,not sure if there is such for channel close...
There should be also possibility to create CPFP TX, however it wosn't the case at the time for me for CLN.
Note - I'm currently using LND.

[har15eld0n]

I already use Zeus, but there is really not anything more to do there (or in RTL) as the channel is considered closed :(
The core issue seems that I have this closing onchain transaction that is stuck at the bottom of the queue, with absolutely no way to interact with it, and do a CFFP for example.

The wallet that can be recovered with hsm_secret seems to be a temporary buffer for onchain markers, but does not know anything about what corelightning is doing onchain 🤔

In this screenshot, there is absolutely no way to see the closing tx, and even the onchain balance is not the one displayed in Zeus or RTL or by using the lightning-cli command

I am dumbfounded 😞

[har15eld0n]

I already use Zeus, but there is really not anything more to do there (or in RTL) as the channel is considered closed :( The core issue seems that I have this closing onchain transaction that is stuck at the bottom of the queue, with absolutely no way to interact with it, and do a CFFP for example.

The wallet that can be recovered with hsm_secret seems to be a temporary buffer for onchain markers, but does not know anything about what corelightning is doing onchain 🤔

In this screenshot, there is absolutely no way to see the closing tx, and even the onchain balance is not the one displayed in Zeus or RTL or by using the lightning-cli command

I am dumbfounded 😞

taproot seems to be the answer, importing the hsm_secret and selecting a taproot type wallet gives you access to a totally different history...

I'll report back later...

[har15eld0n]

So this is what works to speed up a stuck closing channel transaction because of the high fees:

I'll use sparrow as the target wallet software, where we will execute the CFFP transaction to accelerate the original closing tx (as much as it can be accelerate in these very fee times

1. Locate the hsm_secret for your node's on-chain wallet - https://docs.corelightning.org/docs/backup#backup
2. Use one of the following scripts to convert the hsm_secret into an xprv that can be imported in Sparrow

• python based: https://github.com/dieqohc/HSM-to-XPRV-recovery-tool
• C based:https://github.com/jb55/clightning-dumpkeys/

3. Once you have the xprv key, open Sparrow

• Create a new wallet
• Script Type: Taproot
• Keystore: New or imported wallet
• Choose: Master Private Key (BIP32) and enter your xprv, then Import
• Derivation path is m/0
• Apply

4. You should now see your lightning wallet transaction history and from there select your unconfirmed transaction and CFFP it!

Good luck!