duncan@siesoft.co.uk (Duncan McEwan) (08/29/90)
I'm not sure that this is the most appropriate group for this query, but I guess it will reach most of the people who will be able to answer it. I have just started using an exabyte tape drive to do dumps of our file systems. Could someone please tell me the appropriate values to give to dump (tape length, density, inter-record gap (is this relevent for this encoding format?)) to allow dump to fully utilise each tape. For now I am kludging it using a bogus tape length of ~200000 feet (estimated by knowing that dump will write approx 64MB onto a 5400 ft streamer cartridge), but I would like to know the correct values. In particular, how much *can* you fit on a single 90 minute tape, and how long are the tapes? I will summari[zs]e to this group any replies by email that aren't also posted here. Duncan
rsb1@cbnewsk.att.com (richard.s.brown) (09/05/90)
In article <1990Aug29.143657.20588@siesoft.co.uk>, duncan@siesoft.co.uk (Duncan McEwan) writes: > I have just started using an exabyte tape drive to do dumps of our file > systems. Could someone please tell me the appropriate values to give > to dump (tape length, density, inter-record gap (is this relevent for this > encoding format?)) to allow dump to fully utilise each tape. > > For now I am kludging it using a bogus tape length of ~200000 feet (estimated > by knowing that dump will write approx 64MB onto a 5400 ft streamer cartridge), > but I would like to know the correct values. In particular, how much *can* > you fit on a single 90 minute tape, and how long are the tapes? We use 120 min tapes. We bought our drives from Perfect Byte, Inc. in Omaha, Nebraska. The documentation we received was remarkably good (and concise!) Here are the suggested values for 'dump': Blocking factor: 126 Density: 54000 (bpi!!!) Length: 6000 (ft.) I hope this helps! Rich Brown AT&T Network Systems rsb@vogon.att.com