Oh that was so many years ago. I was a member of Jurassic Park Legacy forums around 2009-2011, and the system I did that on is long gone now. I had it replicating the IRIX layout and even the Jurassic Park Alpha BASH with blue background
It was a simple batch file I just messed with, edited the entries for 'permission denied' where after the third time it echos a bunch of 'And...you didn't say the magic word!' scrolling down the screen and starts up some type of frame buffer image to load the GIF. If I'm not mistaken, there's plenty of software resources on that forum. Some guy named Cyrix was doing all the simulations and made a screensaver of the bootup and the Ford Explorer software used in the movie. He had copies of some of the assets I used such as the animated Nedry GIF image.
When I get off work for the end of the year (late November) I planned on toying with Linux on my gaming rig, trying to make games run (properly, not like they're on an i486) using Ubuntu's gaming version. Might try finding some means of bringing that chaos back. I still have the old hard disk from that system but Linux never liked playing well with another motherboard.
Back then, there was a website that was trying to replicate the OS from the movie too, called Jurassic Park OS, or jpOS. It was alpha stage so not fully functional, and the site had to be taken down to find new servers to run, and I never got back to see if it ever came back up. Nice concept though.