On Fri, 6 Apr 2001 at 8:42pm, Jeff Heckart wrote
> Do you feel it a problem to have both the scsi3 internal drive and the raid
> on the same controller? The reason for this was that the internal drive was
> the old one, and the raid has been recently added. The internal isn't
> normally even mounted.
That depends very much on exactly which scsi card you have. You mentioned
that's in an Adaptec scsi2 card. Which model is it? Is it single or dual
channel? Also, is the external connection to which the RAID is connected
really a U2W connection? If that external connection is only, e.g.,
UltraWide, that *may* explain the horrid performance to the RAID.
If the card is dual channel, and the external connection is a separate
channel from the one to which the internal drive is hooked, there's no
problem hooking them both up. If it's single channel, you want to make
sure that the whole chain is operating in LVD mode, which it won't if the
external channel is UW and there's anything on it.
Also, with some Adaptec cards, there's the possibility of cabling up a
Y-shaped SCSI chain, which is never a good thing. What exactly is your
setup?
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED]]On Behalf Of John R. Jackson
> Sent: Friday, April 06, 2001 6:40 PM
> To: Jeff Heckart
> Cc: [EMAIL PROTECTED]
> Subject: Re: large filesystem problems
>
>
> You might also do some serious SCSI chain checkout. For instance, it's
> my understanding you cannot have a narrow device after a wide device
Actually, you can, provided you have an *active* wide->narrow converter in
place, i.e. something that actively terminates the high bit.
> in the same chain. That kind of thing. And termination is always a
> likely culprit.
>
Yep.
--
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University