Automatic HTTPS setting doesn't work

[lucas-mior]

I currently have a server running JupyterHub and when I set automatic https with Let's Encrypt and reloaded proxy, and access JupyterHub, it says the certificate is not valid.
My config.yaml:

user:
    admin:
    - xxxxx
https:
    enabled: true
    letsencrypt:
        email: xxxxx@gmail.com
        domains:
        - xxxxxxx

[lachlancampbell]

I've had this sporadically as well, but I believe its a LetsEncrypt problem rather than a TLJH problem. Sometimes the domain check just fails, and I haven't been able to figure out why. See below for logs from a previous instance:

May 14 05:01:30 ansible-instance python3[18826]: [E 2019-05-14 05:01:30.204 JupyterHub proxy:102] Error checking traefik api for backend /
May 14 05:01:30 ansible-instance python3[18826]: Traceback (most recent call last):
May 14 05:01:30 ansible-instance python3[18826]: File "/opt/tljh/hub/lib/python3.6/site-packages/jupyterhub_traefik_proxy/proxy.py", line 99, in _check_for_traefik_endpoint
May 14 05:01:30 ansible-instance python3[18826]: resp = await self._traefik_api_request(path)
May 14 05:01:30 ansible-instance python3[18826]: File "/opt/tljh/hub/lib/python3.6/site-packages/jupyterhub_traefik_proxy/proxy.py", line 142, in _traefik_api_request
May 14 05:01:30 ansible-instance python3[18826]: auth_password=self.traefik_api_password,
May 14 05:01:30 ansible-instance python3[18826]: ConnectionRefusedError: [Errno 111] Connection refused
...
May 14 05:01:43 ansible-instance traefik[18819]: time="2019-05-14T05:01:43Z" level=error msg="Unable to obtain ACME certificate for domains "tljh.myddns.rocks" : unable to generate a certificate for the domains [tljh.myddns.rocks]: acme: Error -> One or more domains had a problem:\n[tljh.myddns.rocks] acme: Error 400 - urn:ietf:params:acme:error:connection - Fetching http://tljh.myddns.rocks/.well-known/acme-challenge/Paf3ua17jTCO4ixn34Oj2oSyriuTeTewOTBv35ts9Tg: Timeout during connect (likely firewall problem)\n"

[efedorov-dart]

The same issue.

[anthmapper]

I guess that's the same issue:
#115

i actually found a "workaround", and posted it in that thread ;)

[consideRatio]

I'm closing this in favor of #726 which is about adding documentation to help users setup HTTPS more reliably without failing. Also note that Traefik relies on LEGO - a library to acquire HTTPS certificates via the ACME negotiation protocol. Both traefik and LEGO has fixed various bugs over time with regards to this, and I know using a more modern version of Traefik has solved some challenges in the past.

The latest traefik v1 version is v1.7.33, and TLJH now installs 1.7.18. I opened #727 to make us bump it.