Setup Varnish 4.x for CentOS 6.x

[reverendspam]

This tutorial is strictly for Varnish 4.x, Sentora 1.0.x, and CentOS 6.x.

Installation

Log into your server via ssh gaining root access.

IMPORTANT - Make a backup of of your vhosts file.

Code:

cp /etc/zpanel/configs/apache/httpd-vhosts.conf /etc/zpanel/configs/apache/httpd-vhosts.bak.conf

Get the latest version of Varnish from their repositories:

Code:

cat << EOF >> /etc/yum.repos.d/varnish.repo
[varnish]
name=Varnish for Enterprise Linux 6
baseurl=https://repo.varnish-cache.org/redhat/varnish-4.0/el6/
enabled=1
gpgkey=https://repo.varnish-cache.org/GPG-key.txt
gpgcheck=1
EOF

Then install Varnish

Code:

yum install -y varnish

Configure Varnish

Using your favorite editor open /etc/sysconfig/varnish and change "VARNISH_LISTEN_PORT" to

Code:

VARNISH_LISTEN_PORT=80

Using your favorite editor open /etc/varnish/default.vcl and make sure line 16-18 states

Code:

 
backend default {
   .host = "127.0.0.1";
   .port = "8080";

Configure Sentora

set your apache port

Code:

setso --set apache_port 8080

set your sentora port

Code:

setso --set sentora_port 8080

Go to your sentora administration panel to admin --> Module Admin --> Apache Config and set "Apache Port" to "8080".  Tick the "Force Update" box and click on "Save Changes"

restart the apache server

Code:

service httpd restart

start / restart Varnish

Code:

service varnish restart

If all goes well both should restart with no issue and Varnish is running in the front of your apache server.

If for some reason the varnish service is not starting try to start it again. If it still does not start and you think there my be a syntax error somewhere you can run the varnish debug command to see where your error is.

Code:

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

To verify Varnish is working correctly

Going back to you root login via ssh type in the command below replacing 127.0.0.1 with one of your websites.

Code:

curl -I http://127.0.0.1/

You should get back a response that looks similar to this:

HTTP/1.1 200 OK
Date: Tue, 29 Mar 2016 22:43:18 GMT
Server: Apache
Vary: Accept-Encoding,Cookie
Cache-Control: max-age=3, must-revalidate
WP-Super-Cache: Served supercache file from PHP
Content-Type: text/html; charset=UTF-8
X-Varnish: 65560
Age: 3
Via: 1.1 varnish-v4
Connection: keep-alive

Two flags  to that let you know Varnish is working correctly:

X-Varnish: 16
Via: 1.1 varnish-v4


In case something goes wrong


Remove Varnish completely

Code:

yum erase varnish

Restore your vhosts file

Code:

cp /etc/zpanel/configs/apache/httpd-vhosts.bak.conf /etc/zpanel/configs/apache/httpd-vhosts.conf

Set your apache port back to 80

Code:

setso --set apache_port 80

set your sentora port back to 80

Code:

setso --set sentora_port 80

Restart the apache server

Code:

service httpd restart

[Me.B]

If you have more than an IP you can set varnish side by side with sentora each on own IP. So customers can either for example use cdn.domain.com thru varnish ( with extensive and heavy caching ) or use direct access.

M B