Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!crdgw1!uunet!europa.asd.contel.com!gatech!purdue!haven.umd.edu!ni.umd.edu!ni.umd.edu!zben From: zben@ni.umd.edu (Ben Cranston) Newsgroups: comp.sys.mac.misc Subject: Re: Tips for Macs on a student network Summary: Actually you *can* boot from a network Message-ID: <1991Jun17.212135.17640@ni.umd.edu> Date: 17 Jun 91 21:21:35 GMT References: <1991Jun17.165139.575@groucho> <13187@uwm.edu> Sender: usenet@ni.umd.edu (USENET News System) Organization: University of Maryland at College Park Lines: 37 In article <13187@uwm.edu> datta@vacs.uwp.edu (David Datta) writes: > You cannot make the mac boot from the network or use system files > from the network. Actually you can. Since it is a commercial product and I was one of the three people who developed it, I probably shouldn't say too much about it on this non-commercial medium. One of us did a ROM that fits onto an Apple/3Com or Asante ethernet card. This ROM get control early in the boot process and carves out a RAM disk. Then it does a BootP to get a boot file name and a TFTP of the file into the RAM disk. Then the boot continues with the RAM disk as the boot disk. The user gets a perfectly writable system on the RAM disk that goes away the next time the system is booted. Disadvantages: the RAM disk costs memory and System 7 is *MUCH* bigger than System 6. You end up with two copies of the System in memory, one on the RAM disk and another in real executable memory. For each byte the system is bigger, you lose two bytes. My personal feeling is that it should be possible to switch-launch over to a read-only copy of the system on a server at some point during the boot process. You would have to remove all the desk accessories and things that try to write the system file (chooser, monitors, etc) or patch out _Write to ignore write errors on the system file. You would have to figure out how to get "preferences" back onto writable medium, perhaps with a patch to the Folder Manager. Perhaps I should make the final point that there will be a quantum differance in practical experience and expertise between people who "installed a server last month" and people who have been running servers for the last five years... Ben Cranston University of Maryland at College Park And, as of Friday, KA3ZDF -- that's Kilo Alpha Three Zulu Delta Foxtrot!