Recommend CD RW drive for Retrospect Express Mac
Sorry to bother the list with this, but I need some recommendations for a CDR or CDRW SCSI drive that works with Retrospect Express on a mac. I checked the supported devices list on the Dantz site but unfortunately it doesn't really help since (for example) QPS (make of the Que drive) seem to be using totally different part numbers than what Dantz is using. Either that or Dantz doesn't support any currently shipping QPS drives... Or, for example if I look in the MacWarehouse or APS catalogs they don't specify part numbers or OEM mechanism part numbers so I have no idea how to reference that item with what's on the approved list. Anyway... this is for a 7100/80 so I'm stuck with SCSI (no nubus USB or Firewire cards). I'm interested in the QPS CD-RW 6x4x24, external SCSI or APS CD-RW 8x8x24 SCSI Pro2 but don't know if either one works with Retro Express... and I'm totally open to any suggestions even if these do work with it. Thanks in advance, -Greg Morin -- Gregory Morin, Ph.D. ~~~Research Director~~ Seachem Laboratories, Inc. www.seachem.com 888-SEACHEM ~ -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Miscompare on same files every night?
Ok, solved one problem, now I've got another. I'm 99% sure the problem is with our Adaptec 2930U card that our VXA drive is attached to and _not_ the VXA drive. The problem is that now I'm getting miscompares on certain files. The weird thing is that it is the same files every night. The files themselves are fine on the client computer (i.e. no damage, they work just fine). I realize you can get miscompares when a file is in use or has changed since the backup... but these are "not in use" documents on shutdown down systems (waiting for backup of course :-). If the file is modified, the next backup will sometimes get it backed up, sometimes not. I'm afraid to do a new backup, at this rate I'll have thousands of files miscomparing. Before I put the VXA drive on this card it ran off the motherboard SCSI and although slow on that, it never gave me these miscompares. Also, we've been using a DDS-2 drive for over 2 years with no history of miscompares... so it's not a general network problem (happens on backup of local drives also). I highly suspect the 2930 card because I discovered that when I have any hard drive attached to the card externally that any application on that drive will not launch w/o giving some random error (Type 1, 2, 90 something, or a dialog saying the app is damaged). I can move the same drive to the motherboard SCSI bus and all is well... so the files are not really damaged. I played around with every possible configuration of termination and Adaptec settings, nothing works (this was all done with the VXA drive detatched to ensure it was not the source of the problem... ). I've written to Adaptec but haven't heard anything back yet. Anybody else run into a similar problem before? Do I just have a bad card? Do I need to start playing the PCI port roulette game (i.e. moving it from port to port until one of them works)? I vaguely remember something about the port mattering on these 6 port machines... something about a bridge chip and the video board?? (This is a Power Tower Pro 225) Any and all advice/comments would be welcome, -Greg Morin -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Problems?: [EMAIL PROTECTED]
VXA Drive slowdown problem resolved
Hello, Based on Jon Gardner's post in response to my initial query about a speed discrepancy between a DDS-2 drive on a slow SCSI external bus and and the VXA drive on the Fast Internal bus (on a PowerTower Pro 225): Any I/O bus, be it SCSI, network, or whatever, has a limit to the amount of data that can be passing through it at any given moment. This is a bit of a simplification, but if you're trying to read data at full speed from your HD, you cannot simultaneously write at full speed to a tape drive on the same bus, because the bus is saturated with the read. If the tape drive is on another bus, you can read at full speed on one bus and write at full speed on the other bus at the same time. I was able to resolve the slow down problem by putting the VXA drive on its own SCSI Card (Adaptec 2930 card, although I think in principle the less expensive 2906 card would have solved the problem as well). After moving the VXA drive to the 2930 card speed of backup went from average of 40 MB/min to 133 MB/min. In normal use I was seeing backup speeds approaching 180 MB/min across the network when backing up G3 clients (during the compare phaste). I also did a brief test. At first the VXA drive was the only device on the card and I did a test back up of an external hard drive and got around 133 MB/min, then moved that external drive to the external port of the 2930 card and backed up the same files and did indeed get slightly lower numbers (although still perfectly acceptable). So in conclusion, the VXA drive (when installed internally) works fastest when it is not on the same bus as the boot drive and if you're concerned with absolutely the highest speed in backing up local devices, it should be on it's own card all by itself... if you're only concerned with maximum network backup speeds it should just be on a different (preferably Fast SCSI 2 or faster) bus from the boot drive. I'd also like to acknowledge the excellent customer service from Ecrix on this matter. I received rapid responses to my queries and Bob Zegarelli even sent me an active inline terminator so that I could properly test the drive with the 2930 card. Thanks to everyone, -Greg Morin Gregory Morin, Ph.D. ~~~IS Manager~~~ Seachem Laboratories, Inc. www.seachem.com 888-SEACHEM ~ -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Problems?: [EMAIL PROTECTED]
Re: Retrospect and Ecrix VXA
a SuperMac S900 clone (basically a 9500), connected to the mediocre logic-board SCSI, and I still get over 135 MB/min locally. Two more As one of the original posters with slow performance (50 MB/min max locally) then from the above I can only conclude there is some sort of hardware problem with our drive or our computer (Power Tower Pro 225). Since we get _slower_ performance from the VXA drive on the _fast internal_ bus than we do from an old DDS-2 drive on the mediocre external bus. Removing everything from the external bus does not change the performance of an internal drive - VXA backup. The VXA drive is in the middle of the internal terminated Fast SCSI-2 bus. Software compression is off. (i.e. I did NOT check the "allow software compression" box... so I presume this means software compression is off and hardware is on?. The only places I see to set this is when the original back up set is created and within the individual backup server script. Any other place I might be missing to turn off software compression? Thanks for any and all help/advice, -Greg Morin -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Problems?: [EMAIL PROTECTED]
Re: hardware failure
Hi guys (and the girls to if there's any out there on this list!), I've been experiencing frequent but non-the-less erratic Hardware Failures over the last couple of months. I run about 75 clients (all macs) off a 7300/200, to a Sony DSS tape drive. I've been marking the tapes that come up with Hardware errors, to see if there's a pattern. Also, I've tried disconnecting EVERYTHING and letting the tape drive cool for like 8 hours. Also, I've been head cleaning almost twice a week. I can't seem to correlate my actions with any specific results...sometimes one of the options above will seem to help for a few days but then BOOM...Hardware Failure? Is this a buffer underrun proplem or something or is the media (Tapes) the problem? I ordered a new head cleaning tape and 10 new DSS tapes, but does anyone recognize this problem and if so, what do you recommend I do? I don't know if this will help, but we had a DDS-2 drive die on us last December, it never gave us any problems in nearly 2 years of use. APS replaced it with an identical DDS-2 drive... but that one was giving me random hardware failures from day one. Occasionally it would get through the backups without one, but after a week of this I called to get it replaced. They send out a replacement and have had no problems since... so the problem was that drive, not the tapes or my set up (I knew it had to be the drive since it was the only variable in the whole setup). Your problem may lie elsewhere, but don't rule out the drive itself. -Greg Morin -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ Problems?: [EMAIL PROTECTED]
