I’m running a Sentry self-hosted instance on my Docker infrastructure. It basically involves fetching a Git repository and checking out the tag associated with the newest release you wish to install, and running an install script to update the local images.
Anyway, it works fine, but I ran into a new snag thanks to newer Docker in 25.04 RC.1, coming from 24.10.2 after just a month since fresh install.
Apparently, Sentry’s nginx/alpine web proxy that they use to host the main web connection is only configured for IPv4. Attempting to connect to it using IPv6 will result in a connection failure. Let this sink in for a moment.
I am using a cloudflared app tunnel with host networking to bring in several connection points. They’re all configured to connect to http://localhost:someport. Starting with 25.04, this appears to be defaulting to IPv6 connections. This works just fine for all my other Docker containers, as they all seem to support IPv6.
Enter Sentry. Oops, this resulted in a perpetual 502 error from the Cloudflare tunnel, as it reset by peer trying to connect to the Docker container hosting nginx/alpine. So now that’s the only Tunnel connection I have that’s routed to http://127.0.0.1 directly.
I’ll report the bug to them, hopefully they’ll get it fixed in a future version.