Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!ginosko!usc!csun!fedeva!premise!mirror!frog!john From: john@frog.UUCP (John Woods) Newsgroups: comp.unix.wizards Subject: Re: toasted root file system Message-ID: <2090@frog.UUCP> Date: 10 Oct 89 23:09:00 GMT References: <1244@virtech.UUCP> <4469@buengc.BU.EDU> Distribution: comp Organization: Misanthropes-R-Us Lines: 24 In article <4469@buengc.BU.EDU>, bph@buengc.BU.EDU (Blair P. Houghton) writes: > In article <1244@virtech.UUCP> cpcahil@virtech.UUCP (Conor P. Cahill) writes: > >In article , mrd@sun.soe.clarkson.edu (Michael DeCorte) writes: > >> So what do you do if you mangle root? > >You have to have some alternative method of booting the system, otherwise > >how did you get the os on there in the first place. > Monitor-mode, which comes from a prom? > --Blair > "Front-panel switches?" Ah, front-panel switches. Back when I ran a PDP-11, our panic-restore method was quite simple: a short assembly language program named "omg" (for Oh My God), punched on several paper tapes and short enough to toggle in by hand if need be, which would copy a tape image onto the root partition. Every couple of weeks, we'd create a root backup tape with a script named "gmo" (for obvious reasons). On these new-fangled systems without switches, and WORSE YET with complicated controllers requiring gigabytes of code to engage in long philosophical arguments with them just to get data shuffled back and forth, such a brute-force solution might not be so elegant. But it worked. -- John Woods, Charles River Data Systems, Framingham MA 508-626-1101 ...!decvax!frog!john, john@frog.UUCP, ...!mit-eddie!jfw, jfw@eddie.mit.edu