From mboxrd@z Thu Jan 1 00:00:00 1970 From: newsham@lava.net (Tim Newsham) Date: Fri, 2 May 2008 07:05:49 -1000 (HST) Subject: [Unix-jun72] cold boot tape In-Reply-To: References: Message-ID: > I wrote a utility for building a cold boot tape and included it in the > tools directory. Its not yet tested so its possible I got the format > wrong... its based on my reading of init at the end of u0.s. It occurs to me that the tape is probably meant to be bootable. The init program seeks to the 65th block to start booting, so blocks 0 through 64 can be used to hold a bootable kernel image or two. I'm guessing we could make a tape as: blocks 0-31 - the "cold" kernel blocks 32-64 - the real kernel blocks 65- - the contents of /bin and /etc boot the cold kernel from tape, have it write out a primordeal root file system on rf0. Boot the real kernel from tape, have it run the /etc/init that the cold kernel put onto rf0 which reads files from blocks 65 onwards on the tape. Finally reboot the real kernel from tape again and be in a real system. By the way, I made some tape images from the s2 binaries (just /etc and /bin, /usr is probably meant to go onto rk0): http://www.thenewsh.com/%7Enewsham/unix_jun72/tape - the raw tape bits with the first 65 blocks empty http://www.thenewsh.com/%7Enewsham/unix_jun72/tape.tc - a simh format tape of the above bits the tape image isnt tested yet. It should hopefully have the right uids and file modes for first ed. Tim Newsham http://www.thenewsh.com/~newsham/