Does anyone know if the image http://www.tuhs.org/Archive/Distributions/Research/Dennis_v6/v6root.gz is somehow bootable as-is? I wasn't able to figure out how to get it to boot, so I went on a quest to make it bootable. Here's what I did - let me know if this was overkill or misguided. Basically, I downloaded the known bootable v6 distribution tape from Wellsch directory in TUHS. I then extracted 101 blocks from the image (tmrk, a bootblock, and who knows what else, but seriously what else is on those first 100 blocks?), converted it to a simh compatible tape format, and booted a simh generic pdp11/40 with my new little boot tape and Dennis's root disk attached. I used tmrk to copy the bootstrap from my little tape to Dennis's root disk (am I clobbering anything important?). Then voila - it was bootable :)! I could have done it straight off Ken's tape (after converting it to a simh tape format), but I wanted to keep the little tape image around for use in other contexts. Details for the curious are here: https://decuser.github.io/bootable-tape-v6.txt I thought the Ken Wellsch tape was basically the same as the Dennis Ritchie disks, but now I'm not so sure - on Ken's tape, it boots to: @rkunix mem = 1035 RESTRICTED RIGHTS Use, duplication or disclosure is subject to restrictions stated in Contract with Western Electric Company, Inc. # on Dennis' it boots to: @rkunix mem = 1036 # Makes me curious to see what else is different. Maybe Dennis's was prior to preparing an official distro where the rights were added to the kernel? Will -- GPG Fingerprint: 68F4 B3BD 1730 555A 4462 7D45 3EAA 5B6D A982 BAAF