Have not been able to connect to Lightning Terminal Mailbox proxy server via Umbrel Lightning Terminal Connect UI

[debbieNAU]

I am running a Lightning Node via an Umbrel device. Until this morning, I rarely had a problem establishing a connection to Lightning Terminal using the Connect web page on that app within Umbrel. For the last 12 hours, the only message I see is within a big scary orange box:

"Failed to connect.
Not connected. Failed to connect the WASM client to the proxy server. Try reloading the page or obtaining a new pairing phrase."

Reloading the page and/or obtaining a new pairing phrase does not fix the problem.
I can't think of any firewall or any new blockers on my end.
I am using Windows 11 on a standard home Wi-Fi internet connection.

This is the default proxy address; is there any other that I might try?
mailbox.terminal.lightning.today:443

Any suggestions?

[ellemouton]

Hi @debbieNAU - thanks for the issue :)

Do you have access to your LiT server so that you can maybe check the logs for any hint of the problem? On session creation, LiT itself will establish a connection to the mailbox server - so sounds like something is happening at that point

[debbieNAU]

Hi @debbieNAU - thanks for the issue :)

Do you have access to your LiT server so that you can maybe check the logs for any hint of the problem? On session creation, LiT itself will establish a connection to the mailbox server - so sounds like something is happening at that point

Hello Elle: I do have the log of my recent failed attempt tonight, and will attach it as a text file to this message. I surely appreciate if anybody can tell me why LiT doesn't want to let me pass.

umbrel_lightning-terminal_2025-02-06_22-32.log

[guggero]

We fixed something on our end, could you please try again?

[redmac68]

I have the same issue, same symptoms. Using LiT from Raspiblitz. No change when I re-tested now. Previously working well.

[ViktorTigerstrom]

Hi @redmac68, are you still experiencing the same issues? I'm able to connect over LNC, so I wanted to check if you're still encountering any problems.

[redmac68]

Hi Viktor, I am still experiencing the same issues.

[debbieNAU]

Guggero: Success! I was able to log into the Terminal this morning, thank you. If you want to see my log for that session, just let me know and I will happily attach it here.

[ViktorTigerstrom]

Guggero: Success! I was able to log into the Terminal this morning, thank you. If you want to see my log for that session, just let me know and I will happily attach it here.

Great 🎉! Given that you're now successfully able to log in, there's no need for the logs. Thanks for offering to send them though!

Hi Viktor, I am still experiencing the same issues.

If you're still experiencing these issues, could you please send your logs and I'll take a look at them?

[redmac68]

Guggero: Success! I was able to log into the Terminal this morning, thank you. If you want to see my log for that session, just let me know and I will happily attach it here.

Great 🎉! Given that you're now successfully able to log in, there's no need for the logs. Thanks for offering to send them though!

Hi Viktor, I am still experiencing the same issues.

If you're still experiencing these issues, could you please send your logs and I'll take a look at them?

I still have the same problem - but maybe it's not related to this specific issue. Today I updated to LiT 0.14.0 and I restarted litd at 2025-02-07 19:28:41.600 in case that helps debugging. I appreciate any advice you can give me.

litd.log

[ellemouton]

thanks for the logs @redmac68 🙏

seeing this over and over:

2025-02-07 17:14:39.327 [DBG] GOBN: (server) SYNCACK resendTimeout. Abort and wait for client to re-initiate
2025-02-07 17:14:39.327 [DBG] GOBN: (server) Waiting for client SYN
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Received client SYN. Sending back.
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Boosted handshakeTimeout to 10.999999488s
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Waiting for client SYNACK

so we are getting SYN from the client but keep timing out before getting SYNCACK.
Wonder if @ViktorTigerstrom has any thoughts here?

[ViktorTigerstrom]

thanks for the logs @redmac68 🙏

seeing this over and over:

2025-02-07 17:14:39.327 [DBG] GOBN: (server) SYNCACK resendTimeout. Abort and wait for client to re-initiate
2025-02-07 17:14:39.327 [DBG] GOBN: (server) Waiting for client SYN
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Received client SYN. Sending back.
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Boosted handshakeTimeout to 10.999999488s
2025-02-07 17:14:39.335 [DBG] GOBN: (server) Waiting for client SYNACK

so we are getting SYN from the client but keep timing out before getting SYNCACK. Wonder if @ViktorTigerstrom has any thoughts here?

Thanks for the logs @redmac68!

Yes, there definitely seems to be an issue preventing the server and client from reliably exchanging data.

@redmac68, could there be anything in your network setup that might be causing this interference, such as your firewall settings? Have you made any changes to your setup since prior to when everything was working well? Also, are you running over Tor or a VPN?

[redmac68]

Thanks @ViktorTigerstrom.

To answer your questions:

1. I haven't explicitly changed any network configuration or firewall settings relating to my raspiblitz bitcoin/lightning node since the stage when I could connect successfully to
   https://terminal.lightning.engineering.
   1.1 My ISP router has a firewall running which I think can be modified remotely by Vodafone? I have not changed it. If there's something specific that I should check for - let me know.
   1.2 ufw runs locally on my raspiblitz box. ufw config has not changed.

2. I updated LiT to 0.14.0 but this was after I lost the ability to successfully connect to
   https://terminal.lightning.engineering.

3. I run tunnelsats to enable hybrid mode on my node (Clearnet over tunnelsats(WireGuard) VPN and Tor). I run Tailscale VPN to allow remote access.

When I was able to login successfully, it often would not work the first time, but would usually work on the second attempt (straight after the first)?

[ViktorTigerstrom]

Thanks for the detailed information, @redmac68. Just noting that we previously had a user with a similar network setup, where the issue was ultimately found to be unrelated to LNC. However, the way their issue surfaced was not exactly the same way as what you're experiencing: #873

To help determine whether your issue is related to your network setup:
Would you be open to testing the connection without certain network elements enabled (such as the VPN) to pinpoint the root cause? I completely understand if you're not comfortable doing so though, but it could be helpful for troubleshooting and identifying the source of the problem!

[redmac68]

Thanks for the detailed information, @redmac68. Just noting that we previously had a user with a similar network setup, where the issue was ultimately found to be unrelated to LNC. However, the way their issue surfaced was not exactly the same way as what you're experiencing: #873

To help determine whether your issue is related to your network setup: Would you be open to testing the connection without certain network elements enabled (such as the VPN) to pinpoint the root cause? I completely understand if you're not comfortable doing so though, but it could be helpful for troubleshooting and identifying the source of the problem!

Viktor, regarding #873 above, I actually have Zeus wallet on my android mobile phone connected to my raspiblitz bitcoin/lightning node using LNC and it is still working fine.

Regarding testing, I should hopefully be able to do some testing on Thursday. I will try to do the following tests (separately):

1. Turn off Tailscale on my node
2. Use a 5G router to replace the Vodafone VDSL router (and firewall)
3. Update Tor on the raspiblitz node (if you think that this is worth testing)

It's not easy for me to disable tunnelsats hybrid mode safely as the node is in service. So I won't unless I have to?

If there is something else that I should try, please let me know.

[ViktorTigerstrom]

Regarding testing, I should hopefully be able to do some testing on Thursday. I will try to do the following tests (separately):

1. Turn off Tailscale on my node
2. Use a 5G router to replace the Vodafone VDSL router (and firewall)
3. Update Tor on the raspiblitz node (if you think that this is worth testing)

Great, thanks! That sounds like a good first step for troubleshooting. Hopefully you'll notice that you'll be able to connect as soon as one of thee steps are taken, and won't need to proceed with the other steps.

It's not easy for me to disable tunnelsats hybrid mode safely as the node is in service. So I won't unless I have to?

Hopefully you should be able to connect when one of the above steps are taken, and therefore that'll be unnecessary.

I actually have Zeus wallet on my android mobile phone connected to my raspiblitz bitcoin/lightning node using LNC and it is still working fine

Thanks for the information! This suggests that the issue is more likely related to the general network setup rather than LNC itself.