det@hawkmoon.MN.ORG (Derek E. Terveer) (08/06/89)
For those who care, I have struck upon a workaround for the problems that I was encountering when using two floppies in Microport system V/386 3.0e. The problem was (and still is) specifically this: When two floppy drives are simultaneously mounted, performing a umount on one of them doesn't seem to always flush the superblock associatted with that floppy and the system does not seem to flag that device as having been unmounted. Thus, subsequent accesses of that drive will read the previous floppy's superblock, with potentially disasterous results. The floppy doesn't even have to be physically inserted for the os to think that there is indeed a floppy mounted! Quite irritating. My equipment, etc: ACER 1100 386/16MHz Microport System V/386-3.0e, limited Dos Merge 1.1, Limited ~5.5 Mb memory 1 * 72Mb Miniscribe drive 1 * 1.2Mb floppy (drive 0) 1 * 1.44Mb floppy (drive 1) Work around: After umounting the desired floppy and *after* physically inserting the new floppy into the desired drive, but *before* mounting the new floppy fs, run "fsck -n /dev/dsk/????" to clear the superblock. You may then safely mount the new fs. You may, i believe, if you wish to feel safer, run the fsck command with the floppy drive door open, and then perform the mount after fsck aborts. I usually do something like the following: fsck -n /dev/dsk/f1; mount /dev/dsk/f1 /mnt/obj derek -- Derek Terveer det@hawkmoon.MN.ORG || ..!uunet!rosevax!elric!hawkmoon!det w(612)681-6986 h(612)789-8643 "A proper king is crowned" -- Thomas B. Costain