Some of the issues I found include email failure, and users are also redirected to an unreachable interface after registration. Additionally, the default post image wall is also disabled, and none of the uploaded images can be loaded. Even after changing it to port 3443, I found that the Discourse…

Those who have studied the issue know that it won’t work on a non-standard port. I promise. It’s pretty well documented, or so I thought.

I haven’t tried adding these in env yet DISCOURSE_PORT: 3443 DISCOURSE_FORCE_HTTPS: true Don’t know if it will be useful after adding After changing the port, many images fail to load properly, for example https://mydomain/uploads/default/optimized/1X/_129430568242d1b7f853bb13ebea28b3f6af4e7_2_3…

Can I use the following operation when I have disabled nginx inside the container? DISCOURSE_EXTERNAL_BASE_URL: “ https://domain:3443 ”

Moreover, I found that after users log in, they are automatically redirected to https://domain/latest , and the default port 3443 is not added, causing it to fail to load. At this point, you must manually add https://domain:3443/latest .

:face_with_peeking_eye: Thank you for your reply Yes, I know there are many components hardcoded to port 443. My port 443 is not usable, so I had to switch to port 3443. Currently, many functions are not working. I thought someone had studied this issue

It seems I have to give up on this huge project

If it’s not worth a $12/month VM or configuring a reverse proxy, then I think you’re right.

Not about cost. Maybe I want to push it a bit further, like installing multiple Discourse instances on one big server

If you want multiple sites then you either need multisite or a reverse proxy. I usually use traefik, but nginxproxy/nginx-proxy - Docker Image is a little easier. Just add some docker labels and it works.

What adjustments are needed when discourse uses a non-443 port?

Product Support

pfaffman (Jay Pfaffman) November 20, 2025, 3:02pm 5

Discourse won’t work on port 3443. You have to use 443.

Is this a standard install?

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What adjustments are needed when discourse uses a non-443 port?

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