ross@aphasia.UUCP (Ross Harvey) (07/28/85)
I am about to order a new 750 system with some late-model CDC peripherals for use with 4.2BSD. I would appreciate hearing from sites with relevant experience using these peripherals. The proposed configuration is: Emulex SC7000 CDC 9715-500 disk drives (qty 2) Emulex TC7000 CDC 92185-02 tape transport Emulex CS21/F (16 line DMF clone, asynchronous ports only) The 9715 is a 516 MB fixed 9" drive with thin-film heads. It measures only 10.2x8.5x24. The tape transport is a 6250 BPI streamer with a 128K buffer. The disk drives mount side-by-side underneath the horizontally mounted tape transport...this is over 1 GB of disk storage and 6250 BPI tape, all in a cabinet smaller than the 750 CPU. My main concern is the MTBF for the 9715. CDC claims 11,250 hours now but admits to an 8,200 hour figure for the first year of production. The other concern is the streamer. Does it stream under 4.2BSD? I prefer the vacuum column technology but the new technology seems to be going into streamers. Also, I would like to get all the peripherals from one manufacturer that happens to do VAX maintenance, and it turns out that a 6250 BPI vacuum column tape drive apparently costs $300/month for contract maintenance and is initially rather more expensive as well. There are many unbuffered 9218x tape units in use. (The TU80 and TU81 use these transports.) They are slow, the -02 version is new, it has the 128K buffer, and presumably it can stream. (For those who don't know, a streamer that doesn't stream is hopeless.) Of course, I am also interested in experience with basic functionality and level of emulation. I have seen the problem reports on the TC7000. Thanks in advance... Ross Harvey decvax!frog!aphasia!ross ulysses!aphasia!ross lcc!pdc750!aphasia!ross