Eclair Dual-Fund Errors - Fix Interactive Channel Opening Issues

What Is Eclair Dual-Funding?

Dual-funded channels (BOLT2 interactive tx) let both peers contribute funds when opening a channel, improving liquidity from day one.

Common Errors

• dual_funding not supported by peer
• InteractiveTxBuilder: invalid input — utxo already spent
• open_channel2: rbf attempt rejected by peer
• dual-funded channel stuck in WAIT_FOR_DUAL_FUNDING_CONFIRMED

Check Peer Support

curl -u :password http://localhost:8080/peers | python3 -c "
import json,sys
for p in json.load(sys.stdin):
  f = str(p.get('features',''))
  print(p['nodeId'][:20], 'dual_fund:', 'option_dual_fund' in f or '0x200000' in f)
"

Open a Dual-Funded Channel

# Eclair API
curl -u :password -X POST http://localhost:8080/open \
  -d nodeId=<peer_pubkey> \
  -d fundingSatoshis=500000 \
  -d pushMsat=0 \
  -d channelType=AnchorOutputsZeroFeeHtlcTx

Fix Stuck Dual-Funding

# Check pending channels
curl -u :password http://localhost:8080/channels | python3 -c "
import json,sys
for c in json.load(sys.stdin):
  if 'DUAL' in c.get('state','') or 'WAIT' in c.get('state',''):
    print(c['channelId'][:20], c['state'])
"

# Force-close if stuck > 24h
curl -u :password -X POST http://localhost:8080/close \
  -d channelId=<channel_id> \
  -d force=true

Dual-funding issues? DM on Nostr for a free diagnosis.