HTTP/3 over port other than 443

[Candid Dauth]

Hey,

I am trying to get HTTP/3 to run on my server. Due to my specific setup (multiple VMs on one host system with a single public IP address, each VM needing its own HTTP/3 port), I need to run the HTTP/3 UDP listener on a port other than 443.

I am sending the HTTP header Alt-Svc: h3=":44113"; ma=2592000,h3-29=":44113"; ma=2592000.  Firefox makes most subsequent requests through HTTP/3, but Chromium keeps using HTTP/2. When I change my HTTP/3 setup to port 443, it starts working in Chromium as well.

Does Chromium not support HTTP/3 on ports other than 443? What exactly are the rules? Is this documented anywhere? I could not find any information about this anywhere.

Greetings,

Candid Dauth

[Ryan Hamilton]

Chrome does not support alt-svc to ports which are un-privileged:

https://source.chromium.org/chromium/chromium/src/+/main:net/http/http_stream_factory_job_controller.cc;l=1070

So you can use numbers others than 443, but they must be < 1024.

Cheers,

Ryan

--
--
Chromium Discussion mailing list: chromium...@chromium.org
View archives, change email options, or unsubscribe:
http://groups.google.com/a/chromium.org/group/chromium-discuss

[Candid Dauth]

Thank you, it worked!