Are you running a content-heavy dynamic website and looking for ways to enhance your web server’s performance? If so, Varnish Cache could be the solution you need.
Varnish Cache, an open-source proxy server, can significantly reduce server load and increase response times by serving saved copies of pages instead of re-requesting the same revisited page from the web server.
This tutorial will guide you through the process of installing and configuring Varnish Cache with Apache on CentOS 6.5, a popular choice for those running a VPS or a dedicated server.
Step-by-Step Guide to Install Varnish Cache with Apache on CentOS 6.5
We will start by setting up the Varnish repository, followed by the installation of Varnish and Apache. Then we configure both programs to start at boot, set Apache to listen to port 8080, and configure Varnish Cache. After that we will conclude with a performance comparison of Apache with and without Varnish Cache, demonstrating the significant improvement in response times when using Varnish Cache.
Setup Varnish repo:
[root@centos6 ~]# wget http://repo.varnish-cache.org/redhat/varnish-3.0/el6/noarch/varnish-release/varnish-release-3.0-1.el6.noarch.rpm [root@centos6 ~]# rpm --nosignature -i varnish-release-3.0-1.el6.noarch.rpm
Install Varnish and Apache:
[root@centos6 ~]# yum install varnish -y [root@centos6 ~]# yum install httpd -y
Start both at boot:
[root@centos6 ~]# chkconfig --level 345 varnish on [root@centos6 ~]# chkconfig --level 345 httpd on
Configure Apache to listen to port 8080:
[root@centos6 ~]# vi /etc/httpd/conf/httpd.conf
Modify:
Listen 8080
Configure Varnish Cache:
[root@centos6 ~]# vim /etc/sysconfig/varnish
..
..
# # Main configuration file. You probably want to change it :)
VARNISH_VCL_CONF=/etc/varnish/default.vcl
#
# # Default address and port to bind to
# # Blank address means all IPv4 and IPv6 interfaces, otherwise specify
# # a host name, an IPv4 dotted quad, or an IPv6 address in brackets.
# VARNISH_LISTEN_ADDRESS=
#VARNISH_LISTEN_PORT=6081
VARNISH_LISTEN_PORT=80
#
# # Telnet admin interface listen address and port
VARNISH_ADMIN_LISTEN_ADDRESS=127.0.0.1
VARNISH_ADMIN_LISTEN_PORT=6082
#
# # Shared secret file for admin interface
VARNISH_SECRET_FILE=/etc/varnish/secret
#
# # The minimum number of worker threads to start
VARNISH_MIN_THREADS=50
#
# # The Maximum number of worker threads to start
VARNISH_MAX_THREADS=1000
#
# # Idle timeout for worker threads
VARNISH_THREAD_TIMEOUT=120
#
# # Cache file location
VARNISH_STORAGE_FILE=/var/lib/varnish/varnish_storage.bin
#
# # Cache file size: in bytes, optionally using k / M / G / T suffix,
# # or in percentage of available disk space using the % suffix.
VARNISH_STORAGE_SIZE=1G
#
# # Backend storage specification
VARNISH_STORAGE="file,${VARNISH_STORAGE_FILE},${VARNISH_STORAGE_SIZE}"
#
# # Default TTL used when the backend does not specify one
VARNISH_TTL=120
#
# # DAEMON_OPTS is used by the init script. If you add or remove options, make
# # sure you update this section, too.
DAEMON_OPTS="-a ${VARNISH_LISTEN_ADDRESS}:${VARNISH_LISTEN_PORT} \
-f ${VARNISH_VCL_CONF} \
-T ${VARNISH_ADMIN_LISTEN_ADDRESS}:${VARNISH_ADMIN_LISTEN_PORT} \
-t ${VARNISH_TTL} \
-w ${VARNISH_MIN_THREADS},${VARNISH_MAX_THREADS},${VARNISH_THREAD_TIMEOUT} \
-u varnish -g varnish \
-S ${VARNISH_SECRET_FILE} \
-s ${VARNISH_STORAGE}"
#
..
..
Add the following in /etc/varnish/default.vcl :
[root@centos6 ~]# vim /etc/varnish/default.vcl
backend default {
.host = "127.0.0.1";
.port = "8080";
}
Start Varnish and Apache:
[root@centos6 ~]# service varnish start Starting Varnish Cache: [ OK ] [root@centos6 ~]# service httpd start Starting httpd: [ OK ]
Verify Varnish and Apache running on the correct ports:
[root@centos6 ~]# netstat -plunt
Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 1042/rpcbind tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 21729/varnishd tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1075/sshd tcp 0 0 127.0.0.1:6082 0.0.0.0:* LISTEN 21728/varnishd tcp 0 0 :::111 :::* LISTEN 1042/rpcbind tcp 0 0 :::80 :::* LISTEN 21729/varnishd tcp 0 0 :::8080 :::* LISTEN 1182/httpd tcp 0 0 :::22 :::* LISTEN 1075/sshd udp 0 0 0.0.0.0:111 0.0.0.0:* 1042/rpcbind udp 0 0 0.0.0.0:793 0.0.0.0:* 1042/rpcbind udp 0 0 :::111 :::* 1042/rpcbind udp 0 0 :::793 :::* 1042/rpcbind
Verify Varnish running using the following command:
[root@centos6 ~]# curl -I http://www.webhostinggeeks.local HTTP/1.1 200 OK Server: Apache/2.2.15 (CentOS) X-Powered-By: PHP/5.3.3 X-Pingback: http://www.webhostinggeeks.local/xmlrpc.php Content-Type: text/html; charset=UTF-8 Content-Length: 7990 Accept-Ranges: bytes Date: Sun, 13 Apr 2014 15:41:41 GMT X-Varnish: 1889373153 Age: 0 Via: 1.1 varnish Connection: keep-alive
ApacheBench performance test without Varnish Cache
[root@centos6 ~]# ab -k -n 1000 -c 50 http://www.webhostinggeeks.local:8080/
This is ApacheBench, Version 2.3 < $Revision: 655654 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking www.webhostinggeeks.local (be patient)
Completed 100 requests
Completed 200 requests
Completed 300 requests
Completed 400 requests
Completed 500 requests
Completed 600 requests
Completed 700 requests
Completed 800 requests
Completed 900 requests
Completed 1000 requests
Finished 1000 requests
Server Software: Apache/2.2.15
Server Hostname: www.webhostinggeeks.local
Server Port: 8080
Document Path: /
Document Length: 0 bytes
Concurrency Level: 50
Time taken for tests: 217.545 seconds
Complete requests: 1000
Failed requests: 81
(Connect: 0, Receive: 0, Length: 81, Exceptions: 0)
Write errors: 0
Non-2xx responses: 1000
Keep-Alive requests: 0
Total transferred: 318518 bytes
HTML transferred: 20331 bytes
Requests per second: 4.60 [#/sec] (mean)
Time per request: 10877.237 [ms] (mean)
Time per request: 217.545 [ms] (mean, across all concurrent requests)
Transfer rate: 1.43 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 3 12.1 0 65
Processing: 219 10822 17202.8 3275 61139
Waiting: 218 10802 17210.6 3228 61138
Total: 239 10825 17201.5 3275 61139
Percentage of the requests served within a certain time (ms)
50% 3275
66% 4513
75% 5570
80% 12099
90% 40539
95% 60069
98% 60103
99% 60200
100% 61139 (longest request)
ApacheBench performance test with Varnish Cache
[root@centos6 ~]# ab -k -n 1000 -c 50 http://www.webhostinggeeks.local/
This is ApacheBench, Version 2.3 < $Revision: 655654 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking www.webhostinggeeks.local (be patient)
Completed 100 requests
Completed 200 requests
Completed 300 requests
Completed 400 requests
Completed 500 requests
Completed 600 requests
Completed 700 requests
Completed 800 requests
Completed 900 requests
Completed 1000 requests
Finished 1000 requests
Server Software: Apache/2.2.15
Server Hostname: www.webhostinggeeks.local
Server Port: 80
Document Path: /
Document Length: 7990 bytes
Concurrency Level: 50
Time taken for tests: 0.227 seconds
Complete requests: 1000
Failed requests: 0
Write errors: 0
Keep-Alive requests: 1000
Total transferred: 8565396 bytes
HTML transferred: 8221710 bytes
Requests per second: 4410.08 [#/sec] (mean)
Time per request: 11.338 [ms] (mean)
Time per request: 0.227 [ms] (mean, across all concurrent requests)
Transfer rate: 36888.79 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 1 3.2 0 19
Processing: 7 10 1.7 10 18
Waiting: 1 4 2.3 4 15
Total: 7 11 4.1 10 31
Percentage of the requests served within a certain time (ms)
50% 10
66% 10
75% 11
80% 11
90% 12
95% 13
98% 27
99% 31
100% 31 (longest request)
Conclusion
This tutorial provides a comprehensive guide on how to install and configure Varnish Cache with Apache on CentOS 6.5. By following these steps, you can significantly enhance your web server’s performance by reducing server load and increasing response times.
Whether you’re running a VPS or a dedicated web server, implementing Varnish Cache can provide noticeable improvements in your website’s performance.
Did you find this guide helpful? Feel free to leave a comment below. We’d love to hear your thoughts and experiences with Varnish Cache and Apache on CentOS 6.5.
1 Comment
Very useful, thank you.