Re: Add server-id to response header

[Jan-Oliver John]

On 10 November 2011 17:40, Jan-Oliver John<oj...@vz.net>  wrote:
Hi guys,

is it possible to set a response header that includes the server id the
request has been sent to?

Maybe with "rspadd<something>"?
I'm not sure if rspadd is up to the job. I had a quick look and it
looks like the answer is 'no'.

I've got this working with Apache httpd backends though, if you're
using some other server as a backend feel free to ignore everything
that follows. :-)

Instructions are for apache2 on Ubuntu, so adjust as necessary.

Enable mod_headers:

     $ sudo a2enmod headers

Add the following line to /etc/apache2/envvars:

     export HOSTNAME=`hostname`

Add this somewhere in /etc/apache2/httpd.conf:

     #Add server name header so we can identify backend server when
traffic passes through HAproxy
     PassEnv HOSTNAME
     Header set X-Backend-Server "%{HOSTNAME}e %D %t"

You can skip the %t and %D if you want, they just add the timestamp
Apache received the request and the duration of Apaches handling of
the request.

Thanks, Graeme.

This is what i formerly did in Nginx config ;-)

# export HOSTNAME=`hostname`

in nginx.conf:

env HOSTNAME;

http {
    ...
    add_header  X-Backend-Server $HOSTNAME;
    ...
}

I just wondered if it's possible to do this in haproxy and without 
touching the backend's config....mhh, too bad!

Thanks,
Olli