Date: Thu, 13 Nov 1997 10:52:37 -0600 (CST) From: "Daniel M. Eischen" <deischen@iworks.InterWorks.org> To: bicknell@ufp.org, freebsd-hackers@FreeBSD.ORG Subject: Re: AHC / SCSI Problem? Message-ID: <199711131652.KAA24076@iworks.InterWorks.org>
next in thread | raw e-mail | index | archive | help
> We've been having some problems here with FreeBSD, > Adaptec 2940's, and various disk drives. I think we're > hitting some sort of driver bug but would like feedback. > Basically we get these errors from time to time, usualy > during a backup operation. Other than a few complaints > from dump they don't seem to have any operation impact. > I do find it interesting that it happens on the Micropolis > 4221 disks. Perhaps there is something "special" about them. > > I have a theory myself that turning on TAGENABLE and > I have a theory myself that turning on TAGENABLE and > SCBPAGING_ENABLE might actually help this situation, but > I'm not going to try it unless an expert thinks this is a > good idea as well. These are both production machines, so > experimenting is a problem, but if we have some good leads > we can do some work to track this down. > On system number 1 we have: > ahc0 <Adaptec 2940 Ultra SCSI host adapter> rev 0 int a irq 9 on pci0:18 > ahc0: aic7880 Single Channel, SCSI Id=7, 16 SCBs > ahc0 waiting for scsi devices to settle > (ahc0:0:0): "MICROP 4221-09 1128RV 28RV" type 0 fixed SCSI 2 > sd0(ahc0:0:0): Direct-Access 1955MB (4004219 512 byte sectors) > (ahc0:1:0): "MICROP 4221-09 1128RV 28RV" type 0 fixed SCSI 2 > sd1(ahc0:1:0): Direct-Access 1955MB (4004219 512 byte sectors) > (ahc0:2:0): "SEAGATE ST15150N 0022" type 0 fixed SCSI 2 > sd2(ahc0:2:0): Direct-Access 4095MB (8388315 512 byte sectors) Methinks you're leaving out some important information. What is the rest of this list of devices? How is the bus terminated? I'm guessing you're using the tape drive to terminate one end of the bus. If so, don't do that and use one of the drives to terminate the bus as it will (most likely) use active termination as opposed to passive termination that you're probably getting with the tape drive. Aside from possible driver bugs, improper termination and /or cabling is probably at fault. Dan Eischen deischen@iworks.InterWorks.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199711131652.KAA24076>