IPNode Modular root with update management

[rett]

Hello,

I'm releasing a project I've been working on called IPNode. It is used to build a modular root filesystem using AuFS and SquashFS and provide a convenient update management system. It is ideal for use with any device where the OS and configuration needs to be controlled centrally such as network appliances and clusters.

In a nutshell, a root filesystem is constructed out of a core image such as a Gentoo Catalyst Stage4 and various software/configuration packages. For example, a node may be designed to run Asterisk and Apache at a remote site. You may choose Ubuntu Server for the core image, package Asterisk and Apache with corresponding configuration modules containing dial plans and web server configuration. You store the latest versions on a parent node and have your child nodes periodically check for updates, and/or manually trigger an update from the server. If an update is necessary, you can test changes in a controlled environment then add it to the module tree on the parent with a higher revision number.

I generally use Gentoo Catalyst to build a uClibc based root weighing in at about 15mb, and use pkgsets to build application modules. Because modules are mounted read-only, and changes are stored in RAM, flash media is not written to at all until an update is committed. This should give the flash a long and healthy life.

You can find the project at http://www.ipnode.org/ and you can check out the source with SVN (http/https). For details about how it works, see http://www.ipnode.org/trac/ipnode-system/wiki/HowItWorks - It is released under GPLv2 and there is still much work to be done. If you have fixes please create a ticket (preferably with a patch attached) and describe the issue with as much detail as possible. There are definitely bugs, please help me fix them!

At this point you are pretty much expected to understand the Linux boot process, specifically the initrd. I strongly encourage you to read /initrd/init and /initrd/bin/ipn* thoroughly. (The bulk of the code is contained in /initrd/bin/ipnLib) As time goes on I hope to provide everything necessary to automate the build and version management system but in the meantime there is a bit of manual labor involved in getting a system running.

Good Luck!