I recently had the following problem:

• From an unattended shell script (called by Jenkins), run a command-line tool that accesses the MySQL database on another host.
• That tool doesn't know that the database is on another host, plus the MySQL port on that host is firewalled and not accessible from other machines.

We didn't want to open the MySQL port to the network, but it's possible to SSH from the Jenkins machine to the MySQL machine. So, basically you would do something like

ssh -L 3306:localhost:3306 remotehost

This page provides a full overview of PHP's SessionHandler life-cycle - this was generated by a set of test-scripts, in order to provide an exact overview of when and what you can expect will be called in your custom SessionHandler implementation.

Each example is a separate script being run by a client with cookies enabled.

To the left, you can see the function being called in your script, and to the right, you can see the resulting calls being made to a custom session-handler registed using session_set_save_handler().