It was interconnected, so (and I'm making up the syntax, where "nnnn" = real tape drive address and "hash" and "userid" are presumably clear)
MOUNT nnnn FOR userid 181 hash would fail if "hash" didn't match the tape number on the request. At that point I don't think there is a "wrong" drive. -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Paul Gilmartin Sent: Friday, November 7, 2025 6:23 PM To: [email protected] Subject: Re: Ancient history: 3420s On Fri, 7 Nov 2025 16:31:55 -0500, Phil Smith III wrote: >Ah, sorry, I meant to say: it was a physical label on the tape. Kinda an >important detail I omitted! So it wasn't "security" per se, more like the Luhn >on a credit card, to avoid entry error (in this case, "grab error"). > I see; thanks. Does that leave a hazard that at a busy time an operator might mount a tape on the wrong drive but enter the matching hash? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
