letter avatar proxy is playing up, I would disable it ASAP and either point letters directly at us or figure out why it is having issue proxying letter images. As a QUICK workaround you can just default people to use the same avatar by default.
eg: https://community.ubuntu.com/letter_avatar_proxy/v2/letter/s/5f9b8f/240.png takes forever to load and this is causing huge issues on the site.
Thanks @sam. I’ve set the avatar URL directly to https://avatars.discourse.org/v3/letter/{first_letter}/{color}/{size}.png for the moment, that okay? Do you have known IP ranges for the avatar servers, so we can get the holes punched through the firewall, as you’re right it can’t talk to the outside world beyond what we specify.
I filed a bug for the issue with ubuntu.com - good spot, thanks!
Using avatars direct is fine we designed it for large scale use, we added the proxy config cause some people had concerns about tracking (not that we even store logs for avatars but yeah, concerns)
You are going to have to punch through a lot more than avatars though:
Other major issue, you got to put a CDN in front of your S3 (just add cloudfront to the mix or whatever), S3 is not a CDN loading images is slow and expensive. (once you add the CDN via site settings be sure to do a full rebake)