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From: "Amir Y. Rosenblatt" <amir@neuron.net>
Message-Id: <199607231908.PAA01110@prozac.neuron.net>
Subject: Re: SCSI errors and repeated panics
To: rgrimes@GndRsh.aac.dev.com (Rodney W. Grimes)
Date: Tue, 23 Jul 1996 15:08:20 -0400 (EDT)
Cc: amir@neuron.net, freebsd-current@freebsd.org
In-Reply-To: <199607222102.OAA19362@GndRsh.aac.dev.com> from "Rodney W. Grimes" at Jul 22, 96 02:02:19 pm
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> In your configuration it _must_ be set to c) above... see the diagrams
> in the Adaptec manual....

My termination setup is as dictated by the manual.

> Humm... I suspect that the HP C1533 DAT drive has active terminators,
> ie the resistor value will be 110 ohms, and the NEC CD-ROM is using
> passive termination, ie the resitor value will be 220/330 ohm.   I highly
> recommend (and the SCSI-II spec just recommends) that you use active
> termination with Fast SCSI-II.

OK -- this morning I switched the DAT drive and the CD-ROM's places in the 
chain so the DAT drive was at the end and adjusted the termination 
settings on both accordingly.  Then my logs show the following:

^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
^@^@^@^@^@^@^@^@^@^@^@Jul 23 09:24:28 prozac /kernel: sd0(ahc0:0:0): timed 
out in dataout phase, SCSISIGI == 0x0
Jul 23 09:24:29 prozac /kernel: ahc0: Issued Channel A Bus Reset #2. 2 
SCBs aborted
Jul 23 09:24:29 prozac /kernel: ahc0: Issued Channel A Bus Reset #2. 2 
SCBs aborted
Jul 23 09:24:29 prozac /kernel: es:3
Jul 23 09:24:29 prozac /kernel: es:3
Jul 23 09:24:29 prozac /kernel: sd0(ahc0:0:0): NOT READY asc:4,1
Jul 23 09:24:29 prozac /kernel: sd0(ahc0:0:0): NOT READY asc:4,1
Jul 23 09:24:29 prozac /kernel: sd0(ahc0:0:0):  Logical unit is in 
process of be coming ready field replaceable unit: 2
Jul 23 09:24:29 prozac /kernel: sd0(ahc0:0:0):  Logical unit is in 
process of be coming ready field replaceable unit: 2

etc...   for about 5 minutes -- then nothing in the logfile until 4 hours 
later:

Jul 23 09:24:48 prozac /kernel: , retries:4
Jul 23 09:24:48 prozac /kernel: , retries:4
Jul 23 13:53:18 prozac /kernel: mode = 0100600, inum = 23201, fs = /var
Jul 23 13:53:18 prozac /kernel: mode = 0100600, inum = 23201, fs = /var
Jul 23 13:53:18 prozac /kernel: panic: ffs_valloc: dup alloc
Jul 23 13:53:18 prozac /kernel: panic: ffs_valloc: dup alloc
Jul 23 13:53:19 prozac /kernel: 
Jul 23 13:53:19 prozac /kernel: 
Jul 23 13:53:19 prozac /kernel: syncing disks... 10 9 5 FreeBSD 
2.2-CURRENT #0: Sun Jul 21 22:24:59 EDT 1996

And a reboot which lect it sitting until I could run home to fsck all the 
partitions.

I have since disconnected the cd-rom drive altogether.

Any further suggestions?  It's getting muy frustrating -- any and all 
ideas are welcome.

	-Amir