On Wed, 18 Nov 1998, Jiann-Ming Su wrote:
> > Apparently, SCSI support is integrated with BOTH Adaptec "AIC-7890
> > Ultra-2/LVD SCSI" AND "AIC-7860 Ultra/Narrow SCSI-3". Will these be OK for
> > Linux? (Or should that question go to the Kernel list???)
> >
>
> Your best bet is to replace the onboard Adaptec with BusLogic. The
> Adaptec driver has come a long way, but the BusLogic is far more mature.
> Although, I have had good luck with the AIC-7880, I have not with the
> AIC-7870. If something isn't working, you'll know it's not the BusLogic.
This might be reasonable advice if it weren't for
a) the many people that are doing just fine with the 2300 and the
7860/7890 with 2.0.[x>=35] and aic7xxx 5.1.[x>=2]. So there is no
reason to spend money on a buslogic -- the 7890 is a superb U2W
controller and works more or less flawlessly in the 2300.
b) the fact that Dell now supports linux and has made 2300 systems
available to e.g., Doug Ledford for debugging. Dell has more or less
committed itself to ensuring that at least Red Hat linux runs flawlessly
on its systems, probably because they can read wall writing in the form
of ISP server orders accompanied by the plaintive cry: "only if it runs
linux".
c) the fact that Adaptec is being far warmer and fuzzier toward
freebsd/linux than ever before. Adaptec was at Linux Expo. Adaptec
recognizes that linux is becoming a significant market, especially in
the high end where its fancier adapters live (the ones that cost money
and make them a decent margin).
The Adaptec driver is supported by Doug Ledford. Doug Ledford now works
for Red Hat and is being paid to maintain the driver (among other things
I'm sure, but heck, a full-time real live properly employed driver
support person is a total luxury in linux even now). Since I worked
with Doug Ledford fairly extensively during the transition period when
the 7890 support was being added (I had this pile of 2300's, you see,
and was forced to run them diskless until we could come up with a kernel
capable of actually seeing and using its U2W scsi controller) I learned
a LOT about the aic7xxx driver from the inside. This is the Sufi Way
according to Linux -- if it doesn't work, pitch in and help out.
If you help out, it shouldn't be too difficult to get the 7870 thing
straightened out. Doug's new drivers have a debug mode that can really
facilitate this. Be aware, though, that any problems you experience may
or may not be related to the 7870 driver (or any linux driver, this is a
generic remark) not working correctly. Many times problems only exist
for certain hardware combinations, or certain motherboards. These days,
a lot of them are really hardware problems in disguise -- even replacing
an adaptec with a buslogic isn't enough to "prove" that adaptec drivers
have a problem. Maybe you have marginal memory (actually fairly common
on very high end systems these days:-( and the adaptec driver is
good/fast enough to push it past the point where it fails, but the
buslogic is just a bit slower and doesn't. Maybe >>another<< card in
your system is fighting with the adaptec but doesn't fight with the
buslogic (forgive the anamistic view of inanimate hardware, but they ARE
alive, you know;-). Maybe the problem is the mmap problem in the older
kernels and the adaptec driver tweaks it but the buslogics driver
doesn't (which doesn't make it the adaptec driver's fault).
Remember, linux isn't like other operating systems where you call e.g.
Sun or Microsoft and then sit back to wait for six months for a fix --
if they don't laugh at you and say "it's not our problem, contact your
card manufacturer). This is a user maintained system -- you have to
help out, especially with obscure/rare bugs -- or sit back and wait for
six months for somebody else to do it for you.
rgb
Robert G. Brown http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567 Fax: 919-660-2525 email:[EMAIL PROTECTED]
