PHP sessions not being saved in memcache

Question

Running an application using php 5.4 on AWS using the Amazon Linux.

PHP version is PHP 5.4.28. memcache lib installed from the AWS repo is php54-pecl-memcache-3.0.8-1.11

Answer 1

OK, we managed to figure out the issue.

First, we created a simple page that spit out phpinfo(). Note that it is important that you run this thru the web server - running php -i DOES NOT include any overrides that apache may add.

Under the session section, the output lists all the directives, and a "Local Value" and a "Master Value".

The local values had:

session.save_handler    files
session.save_path   /var/lib/php/session

while the master values had:

session.save_handler    memcache
session.save_path   tcp://<endpoint>:11211

It turns out that there's an override installed by default in /etc/httpd/conf.d/php.conf that specifies the files. This appears to be a Redhat/CentOS/Fedora thing.

Removing those values from php.conf fixed the problem.

Answer 2

Both of the major memcache PHP PECL extensions have session handlers. Either will require you to install a PECL module before use.

The Memcache PECL extension session handler is enabled with the following in php.ini:

session.save_handler = "memcache"
session.save_path = "tcp://memcacheServerAddressHere:11211?persistent=1&weight=2&timeout=2&retry_interval=10"

The Memcached PECL extension session handler is enabled with the following in php.ini:

session.save_handler = "memcached"
session.save_path = "memcacheServerAddressHere:11211"

Note that the Memcache extension appears to allow more configuration of the Memcache environment.