There are few things you need to do to install Varnish with Cpanel (WHM):

1. Let Apache listen on port 8080 – you can do it by editing httpd.conf or directly in WHM: Tweak Settings menu -> set value of field Apache non-SSL IP/portto 8080 and Save settings

2. install Varnish on your server:

Execute commands:

#install varnish repository

rpm -Uvh http://repo.varnish-cache.org/redhat/varnish-3.0/el6/noarch/varnish-release/varnish-release-3.0-1.el6.noarch.rpm

#yum installation of Varnish

yum install varnish

3. Edit configuration of Varnish /etc/sysconfig/varnish and change value of VARNISH_LISTEN_PORT to 80

VARNISH_LISTEN_PORT=80

4. Edit Varnish Config: /etc/varnish/default.vcl

Use following content (don’t forget to set correct IP address):

backend default {

  .host = “50.28.31.120”;

  .port = “8080”;

}

sub vcl_recv {

 if (req.url ~ “\.(png|gif|jpg|swf|css|js)$”) {

    return(lookup);

 }

}

# strip the cookie before the image is inserted into cache.

sub vcl_fetch {

 if (req.url ~ “\.(png|gif|jpg|swf|css|js)$”) {

   unset beresp.http.set-cookie;

 }

}

5. Now start Varnish service on your server:

chkconfig varnish on

service varnish start

6. Now you are all set.

Now you can monitor your varnish cache e.g. with commandline tool: varnishstat

if you want to make changes to your varnish configuration, test your configuration changes before restarting varnish with following command:

varnishd -C -f /etc/varnish/default.vcl