Retiring bundle

Way back in the early 1990s, people were already trying to come up with better systems for managing software and configuration on multiple servers. One of those tools was a program called Synctree, written at the University of Michigan. (There is a later LISA paper about version two of that system, from 1998, but here I'm talking about version one.) In the early 1990s, Stanford used Synctree with a configuration store in AFS to manage changes to some central servers.

Synctree was a bit complicated, including mechanisms to overlay multiple sets of configuration files. Stanford also ran it automatically, which caused a few problems when it interacted poorly with bugs in AFS and synced zero-length configuration files. I no longer recall the exact set of reasons that prompted him, but Roland Schemers wrote a much simpler version, called bundle, as a Perl script. Like Synctree, it installed configuration files onto machines from a specification; unlike Synctree, it had a much simpler configuration language (called bundle files) and was run on demand. This was sometime around or before 1994.

My recollection is that it took a few years, but we eventually used bundle as our configuration management for everything (ran manually). I adopted the script and largely rewrote it, and then enhanced it (along with others) with more support for variable substitution and the ability to do in-place edits of files. (You can see its final form in the bundle documentation.) Later, when local package managers became more of a thing, we supplemented it with shell scripts that would do package installation and other mostly one-time setup, but all the configuration files were still managed with bundle.

An amusing bit of trivia: bundle was used briefly in the very early days of Google to manage configuration on Google servers.

The major limitation of bundle was always its file-based view. It didn't manage packages or services, its conditionals were limited to complex in-line file edits and substitution variables, and it didn't have a templating system. We finally decided we needed something better, and after a survey of possibilities, selected Puppet in its very early days. But it took us several years to switch, and even when I left Stanford in 2014 we were still using bundle in a few places in our FAI install process.

I adopted bundle to manage my personal systems and never quite got around to switching when we moved to Puppet for servers. (You can see my old notes on managing systems with bundle, which I left up as a historical curiosity.) But this year I finally finished the migration, and today I moved bundle into my obsolete software list and dropped the Debian package from the unstable section of my Debian repository.

So long, bundle. It's been a long and good run, and this is still one of my best examples of how much life there is in a simple, understandable tool that does a small thing well.