By Mike Boylan, Nick McSpadden
Historically, Mac deployment has been done the traditional way, by configuring a perfect “Golden Master” computer configured just the way you want, and then copying that computer to all your other machines. We’d use tools such as Carbon Copy Cloner or Super Duper to do complete block-level copies of the hard drive onto other computers attached by FireWire cables in Target Disk Mode. It worked well enough, as long as all of your hardware was completely identical.
Such idyllic environments became less and less common. There were enough hardware differences among models that we began to see cracks in our Golden Master foundation. Sometimes, settings didn’t work properly, especially for things like AirPort and other hardware-dependent services. Perhaps an even worse situation – someone would innocently ask, “So, can I get this piece of software installed on just these twelve computers?” So you had to make a separate image for that user base. If the very next day Apple released new updates, you had to update two separate golden masters rather than one. The work only increased dramatically as you added more and more unique configurations, each of which required separate management.
Those days are now over. There are a plethora of tools available for deploying OS X without ever having to rely on thick Golden Masters. The ever-helpful folks at AFP548 developed InstaDMG to allow the creation of “modular” images. The idea of a “modular” image is one in which a never-booted base OS has customized software packages added to it, producing a first-time boot up for the machine that has all the “stuff” you’d want on it already installed. It’s an ideal transition from thick Golden Master images. It has the advantages of speedy deployments (as block-level copies are always nice and fast from DeployStudio), and relatively easy updating. Simply slip in the updated software package into the modular manifest, and rebuild the image – only a few minutes of work followed by 30 minutes of waiting.
The very nature of installing OS X has changed completely with the arrival of Lion and Mountain Lion, which are now downloaded from the App Store rather than shipped on physical media. With this advent of new installation methods, Greg Neagle of Walt Disney Animation Studios produced the “CreateOSXInstallPackage” tool, allowing a package-based install of the OS that doesn’t rely on a base image. Rather than using a base image and adding content to it, OS X Lion and Mountain Lion can now be installed on-the-fly from a live package, and other mechanisms for software deployment can take over once the install is complete.
This leads to the “no-imaging” workflow, in which the software deployment and management system is responsible for all installs. By using Greg Neagle’s Munki tools, the base OS package only has to include the Munki installer and the bootstrap file (which kicks in Munki automatically on first boot). Once the OS has been installed, Munki wakes up and installs the rest of the software according to the manifests provided by your web server. Munki can then maintain software updates and version control, and all the clients need is to be told where to look and what manifest to use.
With tools like these, you can see how easy it is to make changes in the future. It doesn’t involve having to redeploy every single machine under your control whenever there’s a change. A good software deployment system will mitigate much of the needs of reimaging in general. The less time you spend updating images and redeploying them (whether it’s through FireWire/ThunderBolt Target Disk Mode or a NetBoot-based method like DeployStudio), the more time you can spend focusing on the things your clients will really benefit from – fast turn around times for repairs, simple upgrade cycles, and less intrusive ways to ask for new software.
Learn about these strategies and how to implement them in the upcoming “How to Lose 100 Lbs in 100 Days” session in the MacIT Conference. Hosted by Mike Boylan and Nick McSpadden, the session will take place Saturday, February 2 at 11:15am and will cover in-depth implementation of modular and thin workflows for deploying systems and software. If you’ve been waiting for the details of how exactly to make the jump from thick golden-master images, this session will have the information you need!