How to select different backend based on URI when using "mode tcp"

Question

I am using haproxy version 1.6.2

I have enabled http2 using the config below which I need to use "mode tcp". But once I have switched from "mode http" to "mode tcp" I couldn't use acl path_beg to

frontend websocks
    mode tcp
    bind *:443 ssl crt /etc/certs/domain.pem alpn h2,http/1.1 ciphers EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH; no-sslv3
    timeout client 1h
    acl is_api path_beg /api
    acl is_xmpp path_beg /chat
    use_backend api_backend if is_api
    use_backend xmpp_backend if is_xmpp
    use_backend fe_public_tcp if { ssl_fc_alpn -i h2 }
    default_backend fe_public

fe_public
    server fe1 localhost:444 weight 1 maxconn 4096 check inter 10000 ssl verify none        

fe_public_tcp
    mode tcp
    server fe1 localhost:445

api_backend
    server api1 localhost:9966

xmpp_backend
    server xmpp1 localhost:9955

How do I make path_beg and http2 works again? or is there a way to enable http2 without mode tcp?

With mode tcp you cannot have http specific features like different backends based on URI. See also http://serverfault.com/questions/611272/haproxy-http-vs-tcp — Steffen Ullrich, Nov 16 '15 at 12:38
Is there a workaround? or is there another way I can use http2 in haproxy without mode tcp? — forestclown, Nov 16 '15 at 12:52

score 5 · Answer 1 · edited Jun 11 '20 at 10:02

To use protocol specific features you have to use the appropriate mode. Mode tcp gives you only access to tcp specific features, but to get http specific features like choosing the backend based on the URI you need to have mode http.

Unfortunately HTTP/2 looks very different from HTTP/1.x and is not support by mode http currently so you have to use mode tcp. This also means that you cannot make any decisions based on URI as long as you want to support HTTP/2.

Better support for HTTP/2 is expected with haproxy version 1.7. From http://www.haproxy.org/news.html:

May, 15th, 2015 : HTTP/2 is out!

Today, HTTP/2 officially exists as RFC7540 and RFC7541. ... Version 1.6 will not support HTTP/2 yet ... We expect to support it by the end of the year, during the 1.7 development cycle.

How to select different backend based on URI when using "mode tcp"

1 Answers1