Channel Rebalance: Failed to find route for payment

[broadpocket]

Looking for general ideas on how to troubleshoot a failed channel rebalancing. I have a general understanding of the process in how the channels are affected and can successfully do so with other nodes that I own. However I cannot rebalance on nodes that are not owned by me. Below is a log snippet of a rebalance of 1500 sats (fixed fee limit of 4 sats) from a node I own to a node I do not own.

What is the best method to troubleshoot this issue?

2021-09-19 12:33:50.759 [WRN] CRTR: Attempt 4051 for payment e7dbfced983f7233ff38321c4c440a8a1c598c49f4787d7bf08c8774dcac3d85 failed: TemporaryChannelFailure(update=(*lnwire.ChannelUpdate)(0x78e4a00)({
Signature: (lnwire.Sig) (len=64 cap=64) {
00000000 ac 0a a5 c6 42 50 bd 4a d0 8e 18 c9 03 cc b5 95 |....BP.J........|
00000010 8f ff 3b 7d 3f d7 f3 c0 03 99 3c 04 bf ca 49 f3 |..;}?.....<...I.|
00000020 6c d4 79 eb 9d c7 85 3f 37 f5 89 d5 48 5d b8 27 |l.y....?7...H].'|
00000030 49 cf 3d 04 9c 3c 24 a0 ba d8 54 4e 50 3a 32 3f |I.=..<$...TNP:2?|
},
ChainHash: (chainhash.Hash) (len=32 cap=32) 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f,
ShortChannelID: (lnwire.ShortChannelID) 701200:610:1,
Timestamp: (uint32) 1632030343,
MessageFlags: (lnwire.ChanUpdateMsgFlags) 00000001,
ChannelFlags: (lnwire.ChanUpdateChanFlags) 00000000,
TimeLockDelta: (uint16) 40,
HtlcMinimumMsat: (lnwire.MilliSatoshi) 1000 mSAT,
BaseFee: (uint32) 1000,
FeeRate: (uint32) 1,
HtlcMaximumMsat: (lnwire.MilliSatoshi) 39600000 mSAT,
ExtraOpaqueData: (lnwire.ExtraOpaqueData) {
}
})
)@1
2021-09-19 12:33:50.783 [WRN] CRTR: Failed to find route for payment e7dbfced983f7233ff38321c4c440a8a1c598c49f4787d7bf08c8774dcac3d85: unable to find a path to destination
2021-09-19 12:33:50.798 [WRN] RPCS: Unable to send payment: no_route

[saubyk]

Hi @broadpocket
Unclear about the premise here. Channel rebalancing is always for your own node, its never between your node and some other node. Funds exchange between your node and the other node is either a payment or payment routing but not channel rebalancing. So, I am not exactly clear what operation you are trying to execute between your node and the other node.

Regardless, If you are referring to circular rebalancing. It's basically a payment you make to yourselves, which affects a relative change in the channel balances between the channel you send the payment out from and the channel you receive the payment back on.

In the specific example above the error message says "no_route", which can be because of any of the below reasons:

• The fee limit of 4 sats is not high enough to compensate for the routing fee policy set by the nodes routing the payment
• The channel balances on the routing nodes in between are not balanced enough to support the payment of 1500 sats
• Your peer is not well connected and may have its neighbors offline

You can take the following actions to figure out where the problem might be:

• increase the fee limit you are applying
• reduce the payment about to see, how much gets through
• Open more channels to try alternate routes

Hope this helps.

[broadpocket]

Hello @saubyk,

Thank you and the premise is to rebalance a channel I have open with another node. The balance on this node is: Local of 48K and Remote of 10. The 10 sats in the Remote Balance was the result of sending a payment to satoshis.place. I did this to see if I had general connectivity / functionality with this node.

Regarding the reasons for "no_route" - are there tools to determine if one of these reasons may be the issue?

For... The fee limit of 4 sats is not high enough to compensate for the routing fee policy set by the nodes routing the payment
-> ThunderHub shows Base Fee and Fee Rate are both 1 sat. Therefore I think my 4 sats is high enough

The channel balances on the routing nodes in between are not balanced enough to support the payment of 1500 sats
-> How would one check the routes this rebalance would take? 1ML shows this node has 17 million sat capacity. And the channel page according to the same website shows this same 17 million sat capacity with my node having 115k sats.

Your peer is not well connected and may have its neighbors offline
-> How would neighboring nodes that are offline affect the rebalance between myself and this node? It would seem I only need a route to this node and then the rebalancing would work.

Thank you for all the help,
BP

[saubyk]

How are you trying to rebalance? Are you using RTL's circular rebalance?

Please note the the fee limit of 4 sats does not apply to your peer's fee policy. It applies to the other network peers your peer is connected with and there is no way for you to know, what policy they have on their channels. So I would suggest raising the limit and see if that helps.

when you are circular rebalancing, you are sending a payment out through one channel (the one that you want to rebalance) and receive it back on another channel. So the payment completes a circular path going through multiple nodes on the network and coming back to you.

[broadpocket]

I'm using RTL's circular balance. I did retry with larger fee limits however that failed. Your last statement about the hopping of the payment gives me some research to do on my connected nodes and available balances. I'll do some testing and get more info. Thank you.

2021-09-21 11:04:51.589 [WRN] CRTR: Attempt 4055 for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2 failed: TemporaryChannelFailure(update=(*lnwire.ChannelUpdate)(0x64e2d20)({
Signature: (lnwire.Sig) (len=64 cap=64) {
00000000 63 68 e5 e4 33 cb 28 b7 ce 48 35 a2 f2 9f df 84 |ch..3.(..H5.....|
00000010 97 e1 a6 e3 0e c0 8f 73 db 96 ee bd 5d d2 24 07 |.......s....].$.|
00000020 32 c0 03 76 3b b7 ba 77 b2 b0 ae 0f 6c ba 4f a8 |2..v;..w....l.O.|
00000030 a7 38 13 1b 17 7b 2d 3e 11 3a a9 3d bd 70 5b 90 |.8...{->.:.=.p[.|
},
ChainHash: (chainhash.Hash) (len=32 cap=32) 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f,
ShortChannelID: (lnwire.ShortChannelID) 701200:610:1,
Timestamp: (uint32) 1632204637,
MessageFlags: (lnwire.ChanUpdateMsgFlags) 00000001,
ChannelFlags: (lnwire.ChanUpdateChanFlags) 00000000,
TimeLockDelta: (uint16) 40,
HtlcMinimumMsat: (lnwire.MilliSatoshi) 1000 mSAT,
BaseFee: (uint32) 1000,
FeeRate: (uint32) 1,
HtlcMaximumMsat: (lnwire.MilliSatoshi) 39600000 mSAT,
ExtraOpaqueData: (lnwire.ExtraOpaqueData) {
}
})
)@1
2021-09-21 11:04:51.613 [WRN] CRTR: Failed to find route for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2: unable to find a path to destination
2021-09-21 11:04:51.628 [WRN] RPCS: Unable to send payment: no_route
2021-09-21 11:04:53.339 [INF] WTCL: (anchor) Client stats: tasks(received=0 accepted=0 ineligible=0) sessions(acquired=0 exhausted=0)
2021-09-21 11:04:53.339 [INF] WTCL: (legacy) Client stats: tasks(received=0 accepted=0 ineligible=0) sessions(acquired=0 exhausted=0)
2021-09-21 11:05:07.319 [INF] CRTR: Processed channels=0 updates=113 nodes=41 in last 59.999316518s
2021-09-21 11:05:26.433 [WRN] CRTR: Failed to find route for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2: unable to find a path to destination
2021-09-21 11:05:26.447 [WRN] RPCS: Unable to send payment: no_route
2021-09-21 11:05:39.264 [WRN] CRTR: Failed to find route for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2: unable to find a path to destination
2021-09-21 11:05:39.280 [WRN] RPCS: Unable to send payment: no_route
2021-09-21 11:05:53.340 [INF] WTCL: (anchor) Client stats: tasks(received=0 accepted=0 ineligible=0) sessions(acquired=0 exhausted=0)
2021-09-21 11:05:53.340 [INF] WTCL: (legacy) Client stats: tasks(received=0 accepted=0 ineligible=0) sessions(acquired=0 exhausted=0)
2021-09-21 11:05:54.777 [INF] DISC: Broadcasting 225 new announcements in 23 sub batches
2021-09-21 11:06:01.818 [WRN] CRTR: Failed to find route for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2: unable to find a path to destination
2021-09-21 11:06:01.834 [WRN] RPCS: Unable to send payment: no_route
2021-09-21 11:06:07.319 [INF] CRTR: Processed channels=1 updates=101 nodes=34 in last 59.99986895s
2021-09-21 11:06:22.244 [WRN] CRTR: Failed to find route for payment b0bf324221ce3f159732c7ca294827b654b565e5bc4577979791eb1157219ad2: unable to find a path to destination
2021-09-21 11:06:22.261 [WRN] RPCS: Unable to send payment: no_route