What Is Varnish?
Varnish is an HTTP accelerator designed for content-heavy dynamic web sites.
Varnish was designed from the ground up as a reverse web accelerator for inbound traffic.
Varnish Installation
Installation was tested on Ubuntu 9.04, 2.6.28-17-generic with Vanish 2.0.6
Download the latest Varnish version.
Extract the archive. Then
sudo ./configure sudo make sudo make install
You can find VCL flow here.
For proper installation you need 3 files:
1. sudo vim /etc/varnish.vcl. Default configuration from the official site:
sub vcl_recv {
if (req.request != "GET" &&
req.request != "HEAD" &&
req.request != "PUT" &&
req.request != "POST" &&
req.request != "TRACE" &&
req.request != "OPTIONS" &&
req.request != "DELETE") {
/* Non-RFC2616 or CONNECT which is weird. */
return (pipe);
}
if (req.request != "GET" && req.request != "HEAD") {
/* We only deal with GET and HEAD by default */
return (pass);
}
if (req.http.Authorization || req.http.Cookie) {
/* Not cacheable by default */
return (pass);
}
return (lookup);
}
sub vcl_pipe {
# Note that only the first request to the backend will have
# X-Forwarded-For set. If you use X-Forwarded-For and want to
# have it set for all requests, make sure to have:
# set req.http.connection = "close";
# here. It is not set by default as it might break some broken web
# applications, like IIS with NTLM authentication.
return (pipe);
}
sub vcl_pass {
return (pass);
}
sub vcl_hash {
set req.hash += req.url;
if (req.http.host) {
set req.hash += req.http.host;
} else {
set req.hash += server.ip;
}
return (hash);
}
sub vcl_hit {
if (!obj.cacheable) {
return (pass);
}
return (deliver);
}
sub vcl_miss {
return (fetch);
}
sub vcl_fetch {
if (!obj.cacheable) {
return (pass);
}
if (obj.http.Set-Cookie) {
return (pass);
}
set obj.prefetch = -30s;
return (deliver);
}
sub vcl_deliver {
return (deliver);
}
sub vcl_discard {
/* XXX: Do not redefine vcl_discard{}, it is not yet supported */
return (discard);
}
sub vcl_prefetch {
/* XXX: Do not redefine vcl_prefetch{}, it is not yet supported */
return (fetch);
}
sub vcl_timeout {
/* XXX: Do not redefine vcl_timeout{}, it is not yet supported */
return (discard);
}
sub vcl_error {
set obj.http.Content-Type = "text/html; charset=utf-8";
synthetic {"
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>"} obj.status " " obj.response {"</title>
</head>
<body>
<h1>Error "} obj.status " " obj.response {"</h1>
<p>"} obj.response {"</p>
<h3>Guru Meditation:</h3>
<p>XID: "} req.xid {"</p>
<hr>
<address>
<a href="http://www.varnish-cache.org/">Varnish cache server</a>
</address>
</body>
</html>
"};
return (deliver);
}
2. sudo vim /etc/init.d/varnish:
#! /bin/sh
#
# varnish Control the varnish HTTP accelerator
#
# chkconfig: - 90 10
# description: Varnish is a high-perfomance HTTP accelerator
# processname: varnishd
# config: /etc/sysconfig/varnish
# pidfile: /var/run/varnish/varnishd.pid
### BEGIN INIT INFO
# Provides: varnish
# Required-Start: $network $local_fs $remote_fs
# Required-Stop: $network $local_fs $remote_fs
# Should-Start: $syslog
# Short-Description: start and stop varnishd
# Description: Varnish is a high-perfomance HTTP accelerator
### END INIT INFO
# Source function library.
. /lib/lsb/init-functions
retval=0
pidfile=/var/run/varnish.pid
exec="/usr/local/sbin/varnishd"
prog="varnishd"
config="/etc/varnish.vcl"
lockfile="/var/lock/varnish"
# Include varnish defaults
[ -e /etc/default/varnish ] && . /etc/default/varnish
start() {
if [ ! -x $exec ]
then
echo $exec not found
exit 5
fi
if [ ! -f $config ]
then
echo $config not found
exit 6
fi
log_daemon_msg "Starting varnish HTTP accelerator"
log_progress_msg $prog
# Open files (usually 1024, which is way too small for varnish)
ulimit -n ${NFILES:-131072}
# Varnish wants to lock shared memory log in memory.
ulimit -l ${MEMLOCK:-82000}
# $DAEMON_OPTS is set in /etc/sysconfig/varnish. At least, one
# has to set up a backend, or /tmp will be used, which is a bad idea.
if [ "$DAEMON_OPTS" = "" ]; then
echo "\$DAEMON_OPTS empty."
echo -n "Please put configuration options in $config"
return 6
else
echo $DAEMON_OPTS
# Varnish always gives output on STDOUT
start-stop-daemon --start --pidfile $pidfile \
--exec $exec -- -P $pidfile $DAEMON_OPTS > /dev/null 2>&1
retval=$?
if [ $retval -eq 0 ]
then
log_end_msg 0
else
log_end_msg 1
fi
return $retval
fi
}
stop() {
log_daemon_msg "Stopping varnish HTTP accelerator"
log_progress_msg $prog
start-stop-daemon --stop --pidfile $pidfile --retry 10 \
--exec $exec
retval=$?
if [ $retval -eq 0 ] && rm -f $lockfile
then
log_end_msg 0
else
log_end_msg 1
fi
return $retval
}
restart() {
stop
start
}
reload() {
restart
}
force_reload() {
restart
}
rh_status() {
status -p $pidfile $prog
}
rh_status_q() {
rh_status >/dev/null 2>&1
}
# See how we were called.
case "$1" in
start)
#rh_status_q && exit 0
$1
;;
stop)
#rh_status || exit 0
$1
;;
restart)
$1
;;
reload)
#rh_status_q || exit 7
$1
;;
force-reload)
force_reload
;;
status)
rh_status
;;
condrestart|try-restart)
#rh_status_q || exit 0
restart
;;
*)
echo "Usage: $0 {start|stop|status|restart|condrestart|try-restart|reload|force-reload}"
exit 2
esac
exit $?
3. sudo vim /etc/default/varnish
#!/bin/sh DAEMON_OPTS="-p default_ttl=3600 -f /etc/varnish.vcl -s file,/var/cache/varnish.cache,512M"
4. How to configure Apache read here.
So, what do you think ?