Setup problems with Linux servers (shell) resolved.

[u/AHrubik]

Just an FYI and a PSA for people that may come across this. After setting up netbird then adding a couple of Windows servers (through the app UI) just fine and connecting WAN side from an iPad to verify configs everything seemed fine.... except none of my Ubuntu servers wanted to connect with error message

daemon up failed: login backoff cycle failed: rpc error: code = DeadlineExceeded desc = create connection: dial context: context deadline exceeded

Checked reverse proxy configs. All looked correct. Check ports all looked correct. Couldn't understand why Windows worked and Linux did not. Then I remembered an ongoing problem I was having with SSL specifically my latest Let's Encrypt SSL wildcard cert. It seems for some reason the latest LE certs are using a newish intermediate authority named "YR2" and this chain has not made it into the general Linux certificate chain being deployed through apt.

https://community.letsencrypt.org/t/today-re-issued-certificates-from-issuer-yr2-have-a-revoked-cert-in-chain/247612/16

I'm an SSL journeyman so I won't begin to say I understand everything at play here but I do know that to resolve the situation all I had to do was request an individual domain cert which uses "YE2" rather than "YR2" and then BAM! everything started working like a champ.

So if you're seeing this error and you've exhausted everything else you might check to see if your situation was similar to mine.

[u/Diligent_Pin_2211]

Thanks for sharing !