nginx configuration for reverse-proxying icecast2 streaming server.

nginx config for icecast2

server {
	listen 80;
	listen [::]:80;
	server_name radio.example.com;
	proxy_set_header Host $host;
	proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
	proxy_set_header X-Forwarded-Host $host;
	proxy_set_header X-Forwarded-Server $host;
	proxy_set_header X-Real-IP $remote_addr;
	location / {
		proxy_pass http://127.0.0.1:8000/;

		subs_filter_types application/xspf+xml audio/x-mpegurl audio/x-vclt text/css text/html text/xml;
		subs_filter ':8000/' '/' gi;
		subs_filter '@localhost' '@example.com' gi;
		subs_filter 'localhost' $host gi;
		subs_filter 'Mount Point ' $host gi;
		subs_filter '<h1 id="header">Icecast2 Status</h1><div id="menu"><ul><li><a href="admin/">Administration</a></li><li><a href="status.xsl">Server Status</a></li><li><a href="server_version.xsl">Version</a></li></ul></div>' '<!--<div id="menu"><ul><li><a href="admin/">Administration</a></li><li><a href="status.xsl">Server Status</a></li><li><a href="server_version.xsl">Version</a></li></ul></div>-->' gi;

		location /admin/ {
			deny all;
		}

		location /server_version.xsl {
			deny all;
		}
	}
}

server {
	listen 80;
	listen [::]:80;
	server_name radio.internal.example.com;
	proxy_set_header Host $host;
	proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
	proxy_set_header X-Forwarded-Host $host;
	proxy_set_header X-Forwarded-Server $host;
	proxy_set_header X-Real-IP $remote_addr;
	location / {
		proxy_pass http://127.0.0.1:8000/;

		subs_filter_types application/xspf+xml audio/x-mpegurl audio/x-vclt text/css text/html text/xml;
		subs_filter ':8000/' '/' gi;
		subs_filter '@localhost' '@example.com' gi;
		subs_filter 'localhost' $host gi;
		subs_filter 'Mount Point ' $host gi;
	}
}

can we send audio stream from client (butt) through this nginx config?

No. And you should not do it either. See this note from the icecast maintainer: https://stackoverflow.com/questions/51786404/icecast2-running-under-nginx-not-able-to-connect/51786791#51786791