rackow@anl-mcs.arpa (Gene Rackow) (05/18/87)
I hope CDC is listening an I'll get this problem resolved, I hate spending the midnight hours formatting the soon to be powder. I can't afford to replace them with something better (read reliable). Short summary first. Use any drive with a CDC label as a boat anchor only. I have had no problems with the Emulex controller. System setup: Vax 11/780 4.2bsd. Drives are used for user file space and 3rd and 4th swapping drives. Other drives 2/rm05 (root;swap;usr;user), 1/rp06 (tmp;user), 2/rp07(user) 2/9771 (user;swap). Clean "computer-room" enviroment with several other machines and lots of disks. In the years we have had the VAX system, the only OTHER disk problems we have had are 1 crash on an rm05 and 1 failing rp07, each after several years in use. (Side note/Lots of Eagles with NO problems) (Also note other CDC exp. on different systems here.) FLAME ON | AFTERBURNER | NOVA | ... (Lots and Lots of heat) Time to do some yelling about REAL trash ---- We have been using the CDC 9771 drives for about 4 years. The longest time one has gone without a HEAD-CRASH is 16 months. The average is about 10 months. The last one was barely 4 months old. You get very little if any warning that anything is going wrong. A soft error occurs about 10-12 hours before crash, a hard error about 6-8 hours before, and then death. We have had CDC in to repair the drives time and time again. Each time they claim we are the only site with this kind of trouble, but we are about the only place using them that they service from this office. Some interesting notes: 1) For a drive that "has been out and stable" for some time, why is it that every replacement head disk assembly (HDA) looks different. A new filter here, an added bracket there, remove the filter, etc. 2) When the service person arrives and checks the serial number of the HDA, it is a "common" claim of "Oh! That is within serial number range ??-??, where we recognize a problem of crashing heads. This has been fixed recently and you shouldn't have any more problems." As they are leaving I say "Bet I'll see you within the year to replace it." (Quotes not exact as this is usually happening after many hours are spent rearranging file systems to get the users all happy again). They never have denied they will have to replace it again. It is a standing (not funny) joke we have. Turn down AFTERBURNER and remove NOVA We have gone to using the CDC drives as an on-line backup and for material that does not change often. In that way, if we have another failure, we do not loose any work. My own feelings are that if you need lots of tmp, swap, or "I don't care if I loose it" type space, the 9771's are just what you need. We have also had bad luck with the CDC "shoebox" FSD about 500Meg drives. The 2 I have on another system have been replaced 2 times each in the last year. In another building here at the labs they have one that gets replaced every 4-5 months. At the time of my inital replacement the service rep. stated that there was an informal trouble report for drives HDA's under 20,000 and to be forwarned that crashes were coming. Between the first and second set of replacments the number moved from 20k to 35k to 50k and to it's present (I think) resting place of 70000. If someone was to GIVE me a CDC drive I would have to think about it for a long time as to if I would use it or not. I do not like to spend time recovering from crashed heads. They would probably have to throw in some other incentive before I would go for it. FLAME OFF These views are mine and not those of the Lab. With the problems we have had many people in my group will agree with my comments. If anyone wants further comments please feel free to call or email. Gene Rackow ARPA: rackow@anl-mcs.arpa Mathematics and Computer Science Voice: 312-972-7126 Argonne National Lab Argonne Il. 60439
louie@sayshell.umd.edu (Louis A. Mamakos) (05/18/87)
In article <7424@brl-adm.ARPA> rackow@anl-mcs.arpa (Gene Rackow) writes: >Short summary first. Use any drive with a CDC label as a boat anchor only. >I have had no problems with the Emulex controller. This is my experience too. > Each time they claim we are the >only site with this kind of trouble, but we are about the only place using >them that they service from this office. Gee, maybe they should talk to the service folks that "service" the University of Maryland. >2) When the service person arrives and checks the serial number of the HDA, >it is a "common" claim of "Oh! That is within serial number range ??-??, >where we recognize a problem of crashing heads. This has been fixed >recently and you shouldn't have any more problems." We've head this too. "Oh, you don't have the NEW HDA, that's your problem." We bought a 9771 for our system (VAX 11/750, EMULEX controller). It died in about 9 months. The Computer Science Department bought a pair, and they didn't have any problems. That is, until a month or so later. The first one died. New HDA. Big $$. Before the service contract could be put in place the second on did too. More $$. Now, we've got a pile of Eagles around here, and they work real fine. When we need disks, we buy Eagles. They work. CDC has to do something to convince us that their drives, especially the 9771, are reliable. They have a real bad reputation around here. This of course represents my views only, and not those of the University of Maryland. Louis A. Mamakos WA3YMH Internet: louie@TRANTOR.UMD.EDU University of Maryland, Computer Science Center - Systems Programming
rick@seismo.CSS.GOV (Rick Adams) (05/18/87)
We have had 2 CDC 9771's for about 3 years. We have had no problems of any kind with them (This is a vax 780 with Emulex controller). The 9771's monthly maintenance charge is about 1/2 that of an Eagle. That says something about the perceived reliability of the drive to me. --rick
chris@mimsy.UUCP (Chris Torek) (05/18/87)
In article <7424@brl-adm.ARPA> rackow@anl-mcs.arpa (Gene Rackow) writes: >We have been using the CDC 9771 drives for about 4 years. The longest time >one has gone without a HEAD-CRASH is 16 months. The average is about >10 months. ... We have had CDC in to repair the drives time and time >again. Each time they claim we are the only site with this kind of >trouble .... You are not the only site. We have had two for more than one year, and a third for about 6 months. The average time to death of the first two has been 12 months (10 on one, 14 on the other). The third one has not been around long enough to die yet. Restoring 670 megabytes is such fun, -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690) Domain: chris@mimsy.umd.edu Path: seismo!mimsy!chris
ggs@ulysses.homer.nj.att.com (Griff Smith) (05/19/87)
In article <7424@brl-adm.ARPA>, rackow@anl-mcs.arpa writes: > ... > Short summary first. Use any drive with a CDC label as a boat anchor only. > I have had no problems with the Emulex controller. > > Gene Rackow ARPA: rackow@anl-mcs.arpa > Mathematics and Computer Science Voice: 312-972-7126 > Argonne National Lab > Argonne Il. 60439 There was a time when I would have agreed with the above, but our experience over the last year has been the opposite. We thought we had a problem with bad blocks appearing on our 9772 drives, but it turned out to be a bug in the firmware in the Emulex controller. A new set of controller PROMs cured the problem. A year earlier we went through many 340 mbyte CDC drives on our CCI POWER 6/32; it was agreed by CDC and CCI that the drives were lemons, and CCI replaced them with a newer model under our service contract. The CDC drives on our systems are now as reliable as any others I have seen. -- Griff Smith AT&T (Bell Laboratories), Murray Hill Phone: 1-201-582-7736 UUCP: {allegra|ihnp4}!ulysses!ggs Internet: ggs@ulysses.uucp
taw@spar.UUCP (05/19/87)
We have had quite a few problems with our CDC9771 drives. Typically, the failure mode has been death due to HDA failure after 18.00 months of operation. Quite literally, they seemed to die in a predictable sequence based on when they had first been turned on. We had a 100% mortality rate on all the 9771s from one batch. We now have quite a few 9772s, bought before the 71s began to die. These drives seem to work acceptably, but we haven't had them as long enough to be sure that they don't have the same problems. --Tom
sanjour@cvl.umd.edu (Joe Sanjour) (05/22/87)
In article <1686@umd5.umd.edu>, louie@sayshell.umd.edu (Louis A. Mamakos) writes: > We bought a 9771 for our system (VAX 11/750, EMULEX controller). It died > in about 9 months. The Computer Science Department bought a pair, and they > didn't have any problems. That is, until a month or so later. The first > one died. New HDA. Big $$. Before the service contract could be put in > place the second on did too. More $$. > > Now, we've got a pile of Eagles around here, and they work real fine. When > we need disks, we buy Eagles. They work. CDC has to do something to > convince us that their drives, especially the 9771, are reliable. They > have a real bad reputation around here. > > This of course represents my views only, and not those of the University > of Maryland. At least not all of the University of maryland :-) We probably are the only ones on campus who likes the drives. We have two 9771s (VAX 11/785, EMULEX controller). We have had them for more then a year and they have give us abosolutly no problems. Admittedly, we had one that we hadn't installed yet sitting around in its box when the CSC lost theirs. They borrowed it, only to find it DOA. Eagles are fine too. We have a few here as well. They have had no problems for as long as I have been here (> 2 years). > Louis A. Mamakos WA3YMH Internet: louie@TRANTOR.UMD.EDU > University of Maryland, Computer Science Center - Systems Programming ^-^ Joseph Sanjour ARPA: sanjour@cvl.umd.edu (- -) Center for Automation Research UUCP: seismo!cvl!sanjour \_/ University of Maryland (301) 454-4526 College Park, MD 20742