CLN no longer opens Zero Conf Channels to LND

[AnthonyRonning]

Issue and Steps to Reproduce

Sometime since commit 3a39c63, CLN no longer opens zero conf channels to LND.

I have a CLN pinned to that commit and I have one that's on the v23.05rc2.

Both can open up channels just fine to LDK and CLN nodes. However, I'm trying to understand what might have changed so I can figure out what I need to do. Odds are there's some issue on one side or another that I need to get to the bottom of. I cross posted this here: lightningnetwork/lnd#7642

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CLN 3a39c63 (working)

LND v0.16.1:

2023-04-26 22:37:04.139 [INF] FNDG: Recv'd fundingRequest(amt=0.0011 BTC, push=0 mSAT, delay=6, pendingId=e180e9cf786ad5d73a432eaecdc4fd6d56db2733e0b64c14f115023f01b80bcb) from peer(0366abc8eb4da61e31a8d2c4520d31cabdf58cc5250f855657397f3dd62493938a)
2023-04-26 22:37:04.139 [INF] CHFD: Performing funding tx coin selection using 0 sat/kw as fee rate
2023-04-26 22:37:04.193 [INF] FNDG: Requiring 0 confirmations for pendingChan(e180e9cf786ad5d73a432eaecdc4fd6d56db2733e0b64c14f115023f01b80bcb): amt=0.0011 BTC, push_amt=0 mSAT, committype=tweakless, upfrontShutdown=
2023-04-26 22:37:04.193 [INF] FNDG: Sending fundingResp for pending_id(e180e9cf786ad5d73a432eaecdc4fd6d56db2733e0b64c14f115023f01b80bcb)
2023-04-26 22:37:04.292 [INF] FNDG: completing pending_id(e180e9cf786ad5d73a432eaecdc4fd6d56db2733e0b64c14f115023f01b80bcb) with ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1)
2023-04-26 22:37:04.297 [INF] FNDG: sending FundingSigned for pending_id(e180e9cf786ad5d73a432eaecdc4fd6d56db2733e0b64c14f115023f01b80bcb) over ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1)
2023-04-26 22:37:04.299 [INF] CNCT: Creating new ChannelArbitrator for ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1)
2023-04-26 22:37:04.299 [INF] CNCT: ChannelArbitrator(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1): starting state=StateDefault, trigger=chainTrigger, triggerHeight=35125
2023-04-26 22:37:04.299 [INF] NTFN: New spend subscription: spend_id=1, outpoint=a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1, script=0 0632908820df2f2b9869dbeac80132a3bfbab9cc75eaa08fd5ae280ca345c0d2, height_hint=35125
2023-04-26 22:37:04.299 [INF] NTFN: Dispatching historical spend rescan for outpoint=a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1, script=0 0632908820df2f2b9869dbeac80132a3bfbab9cc75eaa08fd5ae280ca345c0d2, start=35125, end=35125
2023-04-26 22:37:04.301 [INF] CNCT: Close observer for ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1) active
2023-04-26 22:37:04.301 [INF] CHBU: Updating on-disk multi SCB backup: num_old_chans=0, num_new_chans=1
2023-04-26 22:37:04.301 [INF] NTFN: Historical spend dispatch finished for request outpoint=a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1, script=0 0632908820df2f2b9869dbeac80132a3bfbab9cc75eaa08fd5ae280ca345c0d2 (start=35125 end=35125) with details: <nil>
2023-04-26 22:37:04.305 [INF] CHBU: Updating backup file at /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/channel.backup
2023-04-26 22:37:04.310 [INF] CHBU: Swapping old multi backup file from /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/temp-dont-use.backup to /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/channel.backup
2023-04-26 22:37:04.311 [INF] CHBU: Updating on-disk multi SCB backup: num_old_chans=1, num_new_chans=1
2023-04-26 22:37:04.312 [INF] FNDG: Peer(0366abc8eb4da61e31a8d2c4520d31cabdf58cc5250f855657397f3dd62493938a) is online, sending ChannelReady for ChannelID(bcb701adf48bec557ba86cda8d3118d6406234f5be600d91e8ff74c3975ae7a7)
2023-04-26 22:37:04.314 [WRN] CHBU: Replacing disk backup for ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1) w/ newer version
2023-04-26 22:37:04.316 [INF] CHBU: Updating backup file at /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/channel.backup
2023-04-26 22:37:04.319 [INF] CHBU: Swapping old multi backup file from /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/temp-dont-use.backup to /data/Dev/Lightning/lnd-linux-amd64-v0.16.1-beta/data/data/chain/bitcoin/signet/channel.backup
2023-04-26 22:37:04.425 [INF] PEER: Peer(0366abc8eb4da61e31a8d2c4520d31cabdf58cc5250f855657397f3dd62493938a): New channel active ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1) with peer
2023-04-26 22:37:04.425 [INF] HSWC: ChannelLink(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1): starting
2023-04-26 22:37:04.427 [INF] HSWC: Trimming open circuits for chan_id=16000000:0:0, start_htlc_id=0
2023-04-26 22:37:04.427 [INF] HSWC: Adding live link chan_id=bcb701adf48bec557ba86cda8d3118d6406234f5be600d91e8ff74c3975ae7a7, short_chan_id=16000000:0:0
2023-04-26 22:37:04.427 [INF] CNCT: Attempting to update ContractSignals for ChannelPoint(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1)
2023-04-26 22:37:04.427 [INF] HSWC: ChannelLink(a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc:1): HTLC manager started, bandwidth=0 mSAT
2023-04-26 22:37:05.335 [INF] NTFN: New confirmation subscription: conf_id=1, txid=a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc, num_confs=6 height_hint=35125
2023-04-26 22:37:05.335 [INF] FNDG: Waiting for funding tx (a6e75a97c374ffe8910d60bef5346240d618318dda6ca87b55ec8bf4ad01b7bc) to reach 6 confirmations

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CLN v23.05rc2 (not working)

LND:

2023-04-26 22:37:03.734 [WRN] CHAC: Unhandled commitment type in channel acceptor request: &{map[12:{} 46:{}]}
2023-04-26 22:37:03.735 [INF] FNDG: Recv'd fundingRequest(amt=0.0011 BTC, push=0 mSAT, delay=6, pendingId=9a6f95eef2f308acf1a8e28402c019b0be14ed76890d6b57dffdca73f0eafcd7) from peer(03315285ceb85cc1d90ee69d30da05953850b05f06cc140e66986cc210e75d90bf)
2023-04-26 22:37:03.735 [ERR] FNDG: channel type negotiation failed: requested channel type not supported
2023-04-26 22:37:03.735 [INF] FNDG: Cancelling funding reservation for node_key=03315285ceb85cc1d90ee69d30da05953850b05f06cc140e66986cc210e75d90bf, chan_id=9a6f95eef2f308acf1a8e28402c019b0be14ed76890d6b57dffdca73f0eafcd7
2023-04-26 22:37:03.735 [ERR] FNDG: unable to cancel reservation: no active reservations for peer(03315285ceb85cc1d90ee69d30da05953850b05f06cc140e66986cc210e75d90bf)

CLN logs:

2023-04-27T03:50:02.552Z DEBUG   lightningd: fundchannel_start: allocating uncommitted_channel
2023-04-27T03:50:02.553Z INFO    lightningd: Will open private channel with node 02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095
2023-04-27T03:50:02.555Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: pid 382458, msgfd 66
2023-04-27T03:50:02.555Z DEBUG   plugin-spenderp: mfc 34, dest 0: fundchannel_start 02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095.
2023-04-27T03:50:02.555Z DEBUG   hsmd: Client: Received message 30 from client
2023-04-27T03:50:02.555Z DEBUG   hsmd: Client: Received message 10 from client
2023-04-27T03:50:02.555Z DEBUG   hsmd: new_client: 595
2023-04-27T03:50:02.556Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-hsmd: Got WIRE_HSMD_GET_PER_COMMITMENT_POINT
2023-04-27T03:50:02.556Z DEBUG   hsmd: Client: Received message 18 from client
2023-04-27T03:50:02.556Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: funder_channel_start
2023-04-27T03:50:02.556Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: Setting their reserve to 1100sat
2023-04-27T03:50:02.556Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: peer_out WIRE_OPEN_CHANNEL
2023-04-27T03:50:02.556Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: billboard: Funding channel start: offered, now waiting for accept_channel
2023-04-27T03:50:02.672Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: peer_in WIRE_ERROR
2023-04-27T03:50:02.672Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: aborted opening negotiation: They sent error channel 6ca0f3f86dc554d48e22ed902860fb3baf8d209692c24e2f7a4a897d558bbbf1: funding failed due to internal error
2023-04-27T03:50:02.672Z DEBUG   02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095-openingd-chan#595: billboard perm: They sent error channel 6ca0f3f86dc554d48e22ed902860fb3baf8d209692c24e2f7a4a897d558bbbf1: funding failed due to internal error
2023-04-27T03:50:02.673Z DEBUG   plugin-spenderp: mfc 34, dest 0: failed! fundchannel_start 02a5a83747e3308dacd3769f014b5c504e0dfc73930b2278c63c8f1b1ce76cf095: {\"code\":-1,\"message\":\"They sent error channel 6ca0f3f86dc554d48e22ed902860fb3baf8d209692c24e2f7a4a897d558bbbf1: funding failed due to internal error\"}.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: parallel channel starts done.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: trying redo despite 'fundchannel_start' failure (They sent error channel 6ca0f3f86dc554d48e22ed902860fb3baf8d209692c24e2f7a4a897d558bbbf1: funding failed due to internal error); will cleanup for now.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: cleanup!
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: unreserveinputs task.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: Filtering destinations.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34, dest 0: failed.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: 1 destinations failed, failing.
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: cleanup!
2023-04-27T03:50:02.694Z DEBUG   plugin-spenderp: mfc 34: cleanup done, finishing command.

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The thing that stands out is:

2023-04-26 22:37:03.734 [WRN] CHAC: Unhandled commitment type in channel acceptor request: &{map[12:{} 46:{}]}

When I look at the LND switch case that handles that, I do not see one that just handles those two channel type features: https://github.com/lightningnetwork/lnd/blob/fdc1ae9d57326cc82899e4c76d5069b14a764b96/chanacceptor/rpcacceptor.go#L274-L346

Being just StaticRemoteKeyRequired & ScidAliasRequired.

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Question for CLN:

• Did something change with the channel types being passed for zero conf?
• Did I maybe improperly configure my CLN or some config flag I need?

[morehouse]

Looks related to 7e5146a.

[AnthonyRonning]

It looks like the release was cut anyways despite the interoperability regression between LND, if that's something you guys care about @rustyrussell @cdecker?

I was going to recommend reverting that commit but this has gone unanswered. I guess we'll have to stay at the december release and ignore all the updates we had to do in order to use the deprecated list peers function in this release.

[vincenzopalazzo]

Sorry to be late here, I do not know why I did not receive the email regarding it.

In any case I will try to look inside it :)

[rustyrussell]

Obviously LND didn't expect this combination, which is perfectly valid :(

We used to not set scidalias, which was wrong (how else would we support zeroconf?) but that code explicitly allows :(

Hard to fix (well, until zero fee anchors is merged), but I'll take a look...

[AnthonyRonning]

Is zero fee anchors close to finishing? Perhaps it's fine to wait on that if they'll both be in the next release anyways.