ConnectionError: HTTPSConnectionPool(host='', port=443): Max retries

Indico in a DMZ behind a proxy server

  • ConnectionError: HTTPSConnectionPool(host=‘’, port=443): Max retries exceeded with url: /avatar/d5cf319db7fd313bf941838387228a17?forcedefault=y&s=80&d=identicon (Caused by NewConnectionError(’<urllib3.connection.HTTPSConnection object at 0x7f5942337210>: Failed to establish a new connection: [Errno 101] Network is unreachable’,))
  • this results in a crash of the indico instance, and a restart after a few minutes

Proxy is configured via system.
Downloading succeeds without any problem with wget

How exactly does it “crash”? I’d only expect an error on the profile picture selection page since we store copies of gravatars locally.

Anyway, the standard http_proxy and https_proxy env vars should work - but you need to make sure they are set for the uwsgi and indico-celery services!

Crash: unresponsive for a couple of minutes.
I think, i hope, i found the problem.
All host have configuration management, and I had in no-proxy the usual localhost and internal domain stuff, but also 192.*, for a previous issue with docker instances.