After installing memcached daemon, we have to install memcache PHP extension.

yum install php-pecl-memcache

or

apt-get install php5-memcache

If above is not an option try below method.

pecl install memcache

After successful installation add memcache.so extension to your php.ini file.

vim /etc/php.ini

Add this line:

extension=memcache.so

Restart web server

service httpd restart

Test out our installation.

<?php
$memcache = new Memcache;
$memcache->connect('localhost', 11211) or die ('Can\'t connect!');
$version = $memcache->getVersion();
echo 'Server version: '.$version;

You should see your server’s version number. If you see a blank page make sure that memcached daemon is working. If you’re getting "Can’t connect!" message despite running daemon try changing 'localhost' to '127.0.0.1'.