BRUSYS is a standalone system that runs without any disk. Yep, that's what I thought. It has all the necessary tasks in order to install a distribution on a disk. This is a system that is only intended for when you boot from tape. Well, that's one use. But you can also use it to backup or copy the system disk too (e.g. a disk to disk transfer). That part is even documented in the RSX manual. If you copy BRUSYS.SYS to another disk, it should work just as well as from the original disk. Sounds good, but in practice it doesn't. Sorry... So, whatever you did when you copied the file over to another disk was probably not doing what you thought you were doing. UFD DL0:[6,54] PIP DL0:[6,54]/CO=DU0:[6,54]*.* Any bootable disk is normally created by doing a build of a normal RSX system, copy all the files to the target disk, do a VMR on the target disk, boot the result, and then do a SAV /WB to dump the memory, and update the boot block. Yep, that's basically what I did to create the bootable RSX system on DL0 from DU0. If you have any other suggestions, please let me know. I'd really like to get S/A BRU working on DL0. Thanks, Bob