[bug]: rebalance payment stuck and cause force close

[scissorstail]

Background

Describe your issue here.

Your environment

• 0.15.5-beta
• Linux server 5.15.0-67-generic x86_64 x86_64 x86_64 GNU/Linux
• bitcoind:v24.0.1
• Using docker image from lightninglabs/lnd:v0.15.5-beta, bitcoind is running on another machine and connected with RPC

Steps to reproduce

During rebalancing, sometimes certain attempts do not resolve until they are force-closed.
I have confirmed that all nodes on the rebalancing path are alive.

There are currently two HTLCs in the same situation, with 64(resolved) and 95 hours left until expiration, respectively.
I am losing channels little by little.

Expected behaviour

Rebalance HTLC resolved

Actual behaviour

Rebalance HTLC not resolved and finally force-closed

[alexbosworth]

what is your cltv delta?

[scissorstail]

It is 144.

[ziggie1984]

; A period to wait before for closing channels with outgoing htlcs that have
; timed out and are a result of this nodes instead payment. In addition to our
; current block based deadline, if specified this grace period will also be taken
; into account. Valid time units are {s, m, h}.
; payments-expiration-grace-period=30s

Set this in your config to a very high value and you should be fine!

[scissorstail]

Since the two mentioned HTLCs have been resolved, I cannot be certain if the rebalance was the cause. As it's resolved now, I close this issue. thanks.

[scissorstail]

It happened again today in front of me and I checked the logs. It is a duplicate of #7180
But I don't know why this is happening almost once a week. I think it would be better to reduce the rebalance attempts.