Empty variable $proxy_add_x_forwarded_for, nginx 1.2.3

Question

Nginx

I configure nginx/1.2.3 (debian 6.0.5) as a reverse proxy to tomcat, the config is as follows:

upstream tomcat {
    server 127.0.0.1:8080;
}

server {
    listen   *:80; ## listen for ipv4

    sendfile on;
    charset utf-8;

    server_name  test.ru www.test.ru;

    access_log  /var/log/nginx/test.ru.access.log;
    error_log  /var/log/nginx/test.ru.error.log;

    root /var/www/test.ru/htdocs;

    location / {
            proxy_pass http://tomcat;
            proxy_set_header Host $host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Real-IP $remote_addr;
    }
}

In the jsp page, I display all the headers and their values:

......
x-real-ip	92.47.ххх.ххх
connection	close
cache-control	max-age=0
......

Those. x-real-ip is passed, but X-Forwarded-For is not. What can be wrong?

Answer 1

In general, I solved the problem, you need to write the following in the tomcat in server.xml (it worked after adding the requestAttributesEnabled="true" attribute to AccessLogValve):

<Host name="localhost"  appBase="webapps"
            unpackWARs="true" autoDeploy="true">
    ...
    <Valve className="org.apache.catalina.valves.RemoteIpValve"
           remoteIpHeader="X-Forwarded-For"
           requestAttributesEnabled="true"
           internalProxies="127.0.0.1"  />

    <Valve className="org.apache.catalina.valves.AccessLogValve"
           directory="logs"
           prefix="localhost_access_log."
           suffix=".log"
           requestAttributesEnabled="true"
           pattern="%h %l %u %t "%r" %s %b" />
    ...
</Host>

Answer 2

Why did you decide that the variable is empty and the header is not passed? Look at the same tcpdump, most likely everything is transmitted, just tomcat processes this header as it sees fit.

Answer 3

We go to the off documentation nginx.org/ru/docs/http/ngx_http_proxy_module.html and at the very bottom we read:
$proxy_add_x_forwarded_for

поле заголовка запроса клиента “X-Forwarded-For” и добавленная к нему через запятую переменная $remote_addr. Если же поля “X-Forwarded-For” в заголовке запроса клиента нет, то переменная $proxy_add_x_forwarded_for равна переменной $remote_addr.

Answer 4

mod_rpaf? What does mod_rpaf have to do with it (a quick google shows that this is a module for apache, I have apache tomcat )