The following post is a tutorial on how to install memcached and memcache php extension on Centos 5. Before you start there are a few useful points that might come in handing if you come across any errors.

php.ini file is kept in /etc/php.ini To find out where your php.ini file is kept you can type the following command php -i | grep php.ini

The default extensions loaded are kept in this folder /etc/php.d/

The actual php extensions are kept in /usr/lib64/php/modules/

Install Memcached

Enable the following repository.

For i386 / i686 rpm -Uhv http://apt.sw.be/redhat/el5/en/i386/rpmforge/RPMS/rpmforge-release-0.3.6-1.el5.rf.i386.rpm

For x86_64 rpm -Uhv http://apt.sw.be/redhat/el5/en/x86_64/rpmforge/RPMS//rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm

Use the command Yum to install memcached yum -y install memcached

If no error popup then you have successfully installed memcache. You should then configure memcache by typing the following command. vi /etc/sysconfig/memcached

you should see:

PORT="11211"    #define on which port to urn
USER="nobody"   #same as apache user
MAXCONN="1024"  #maximum number of connections allowed
CACHESIZE="64"   #memory used for caching
OPTIONS=""   #use for any custom options

Start memcached /etc/init.d/memcached start

Check it running /etc/init.d/memcached status

or netstat -anp | grep 11211

To stop / restart memcache

service memcached stop
service memcached restart

To See Memory Memcached Slabs

memcached-tool IP_ADDRESS:Port
memcached-tool IP_ADDRESS:Port display
memcached-tool 127.0.0.1:11211

To See Memory Memcached Stats

memcached-tool IP_Address:Port stats
memcached-tool 127.0.0.1:11211 stats

Install Memcache PHP Extension

Download and install lastest memcache version.

cd /usr/src
wget http://pecl.php.net/get/memcache-2.2.5.tgz
tar zxvf memcache-2.2.5.tgz
cd memcache-2.2.5
phpize
./configure
make
make install

“configure: error: no acceptable C compiler found in $PATH”

If for some reason the above code errors saying something like you do not have a compiler installed run the following command. yum install gcc

Add memcache extension to php.ini file (depending on your version of PHP you may not need this step) vi /etc/php.ini

Press i

Scroll don until you see a large block of code saying extension = …. Then add the following extension = "memcache.so"

To check memcache is correctly installed with php php -i | grep memcache

Finally Restart Apache /etc/init.d/apache2 restart

Special Thanks

This post would not have been possible without the follow tutorials and articles. I highly recommend you check them out as they list different techniques and include other information like how to start memcache as a service.

http://www.cyberciti.biz/faq/rhel-fedora-linux-install-memcached-caching-system-rpm/
http://codelikezell.com/how-to-install-memcached-on-centos/
http://www.lullabot.com/articles/installing-memcached-redhat-or-centos
http://www.sohailriaz.com/how-to-install-memcached-with-memcache-php-extension-on-centos-5x/