docker/mod/nginx/bbb/notes.nginx

# https://github.com/ether/etherpad-lite/wiki/How-to-put-Etherpad-Lite-behind-a-reverse-Proxy
location /pad/p/ {
    # Avoid setting the user name from the embedded URL
    if ($arg_userName) {
        return 401;
    }
    rewrite /pad/p/(.*) /p/$1 break;
    rewrite ^/pad/p$ /pad/p/ permanent;
    proxy_pass http://etherpad:9001/p;
    proxy_pass_header Server;
    proxy_redirect /p /pad/p;
    proxy_set_header Host $host;
    proxy_buffering off;

    proxy_set_header X-Real-IP $remote_addr;  # http://wiki.nginx.org/HttpProxyModule
    proxy_set_header X-Forwarded-For $remote_addr; # EP logs to show the actual remote IP
    proxy_set_header X-Forwarded-Proto $scheme; # for EP to set secure cookie flag when https is used
    proxy_http_version 1.1;

    auth_request /bigbluebutton/connection/checkAuthorization;
    auth_request_set $auth_status $upstream_status;
}

location /pad {
    rewrite /pad/(.*) /$1 break;
    rewrite ^/pad$ /pad/ permanent;
    proxy_pass http://etherpad:9001/;
    proxy_pass_header Server;
    proxy_redirect / /pad/;
    proxy_set_header Host $host;
    proxy_buffering off;
}

location /pad/socket.io/socket.io.js {
    rewrite /pad/socket.io/socket.io.js /socket.io/socket.io.js break;
    proxy_pass http://etherpad:9001/;
    proxy_set_header Host $host;
    proxy_buffering off;
}

location /pad/socket.io {
    rewrite /pad/socket.io/(.*) /socket.io/$1 break;
    proxy_pass http://etherpad:9001/;
    proxy_redirect / /pad/;
    proxy_set_header Host $host;
    proxy_buffering off;
    proxy_set_header X-Real-IP $remote_addr;  # http://wiki.nginx.org/HttpProxyModule
    proxy_set_header X-Forwarded-For $remote_addr; # EP logs to show the actual remote IP
    proxy_set_header X-Forwarded-Proto $scheme; # for EP to set secure cookie flag when https is used
    proxy_set_header Host $host;  # pass the host header
    proxy_http_version 1.1;  # recommended with keepalive connections
    # WebSocket proxying - from http://nginx.org/en/docs/http/websocket.html
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "Upgrade";

    auth_request /bigbluebutton/connection/checkAuthorization;
    auth_request_set $auth_status $upstream_status;
}

location /static {
    rewrite /static/(.*) /static/$1 break;
    proxy_pass http://etherpad:9001/;
    proxy_set_header Host $host;
    proxy_buffering off;
}