rConfig is a free open source network device configuration management utility for network engineers to take frequent configuration snapshots of their network devices. rConfig is unique, because you choose what commands you want to run against your devices. Simply configure rConfig with the list of commands you wish to apply to a category of devices, and add devices to the category. Create a scheduled task, and rConfig will do the rest.
rConfig is completely open source, meaning, you can customize it, and add features as you please. rConfig is written in native PHP. You will not have to install any extra modules to PHP for rConfig to work.