JOHNC%CAD2.DECnet@GE-CRD.ARPA.UUCP (02/19/87)
Kevin Oberman writes in response to ANK's question on bad block files: >>There comes a time when all of us are forced to use old disks, or >>disks that have something that one does'nt need. So, we had an >>unfortunate crash, and a new DRA0: or SYS$SYSTEM disk had to be made >>from a backup. > >It's not the lack of BADBLK.SYS that is bothering you. BADBLK.SYS is a >VMS file and is never on a disk until after initialization. What is >missing is the Manufacturer's Bad Block information which is (was?) >written on the last track of the disk when the manufacturer checked >the media prior to shipping. This information is also missing from >many and perhaps all disks purchased form third parties. > >While the information that may have been in this area is lost forever, >I believe that this area may be recreated by one of the diagnostics. >Either EVRAA or EVRAC. I think the required section is PACKINIT. If >you lack DEC diagnostics, many third party disk vendors supply code to >perform this function with their systems. I know SI does. This is the sequence I have used on a DEC RP06 disk when it got it's MDBBF (Manufacturer's Detected Bad Block File) creamed. $ set def [sysmaint] $ run essaa ds> att rh780 sbi rh0 8 5 ! note: this must describe your ds> att rp06 sh0 dba0 ! disk. Field service should be ! able to help. This says "There's ! a massbus on the SBI at nexus 8, and an RP06 that's called dba0 at ! unit 0 on the massbus ds> sel dba0 ds> run evrac/sec:packinit .... Program Testing:_dba0: DISK TYPE = PACK STRUCTURE = PACK LABEL= <label> PACK IS NOT LABELED SCRATCH ******* WARNING ******** Do you wish to continue? Y CTRL C after format has finished ds> SUMMARY ds> CTRL Y $ mcr bad ! now you can run BAD bad> dba0:/list bad> ctrl Y $ init dba0: <label> ! and init the disk Good Luck! ------------------------------------------------------------------------- "If you feed a starving dog he will John Child not turn around and bite your hand. GE Aircraft Engines That is the principle difference between Lynn MA a dog and a man." - Mark Twain