CAM status: CCB request completed with an error

[Ian Smith]

In freebsd-questions Digest, Vol 513, Issue 5, Message: 29
On Thu, 3 Apr 2014 03:40:09 -0400 kpneal at pobox.com wrote:
 > On Wed, Apr 02, 2014 at 03:48:21AM -0700, Ronald F. Guilmette wrote:
 > > 
 > > What the bleep is a "CCB request", and why would it fail, over and over and over
 > > again, ad infinitum?
 > 
 > Dunno. Try asking on either one of the freebsd-scsi or freebsd-geom lists.

Sure, but meanwhile there's plenty of useful information "out there" ..

googling 'SCSI CCB'; very first hit here is "The Design and 
Implementation of the FreeBSD SCSI Subsystem" by Justin Gibbs: 
http://people.freebsd.org/~gibbs/ARTICLE-0001.html

googling 'SCSI CDB'; first hit is http://en.wikipedia.org/wiki/SCSI_CDB 
which leads to http://en.wikipedia.org/wiki/SCSI_command and such.

 > Maybe for the same reason I can't sleep despite trying over and over again
 > for hours now? Nevermind. :)
 >  
 > > Obviously, this has something to do with the second drive in my system, but I
 > > mean seriously (?) Come on!  Did somebody fail to implement some logic that
 > > would recognize when there have been several thousand such errors already
 > > logged and then, you know, avoid filling up /var/log/messages with even more
 > > of these utterly incomprehensible (and thus utterly useless) error messages?
 > 
 > Well, syslogd does eliminate duplicate messages with a message about having
 > avoiding repeating itself X number of times. But that only works for log
 > lines that are a single line long.
 > 
 > It would be a useful addition to have syslogd recognize repeated groups
 > of log lines and give them the same treatment.
 > 
 > It would be a shame to have various subsystems in the kernel have to roll
 > their own. And it wouldn't solve the problem of userland users of the
 > syslog service having the same problem. Really, the best place for this
 > deduplication would be in syslogd.

That could be nice indeed, Kevin, as perhaps would compressing at least 
some of the CAM messages into more human-comprehensible form.  However, 
the messages in question:

| Apr  2 03:40:31 segfault kernel: (da0:umass-sim0:0:0:0): READ(10). CDB: 28 0 0 1e 6f ff 0 0 1 0
| Apr  2 03:40:31 segfault kernel: (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
| Apr  2 03:40:31 segfault kernel: (da0:umass-sim0:0:0:0): Retrying command
| Apr  2 03:40:37 segfault kernel: (da0:umass-sim0:0:0:0): READ(10). CDB: 28 0 0 1e 6f ff 0 0 1 0
| Apr  2 03:40:37 segfault kernel: (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
| Apr  2 03:40:37 segfault kernel: (da0:umass-sim0:0:0:0): Retrying command

repeated every few seconds clearly enough indicate disk READ(10) errors, 
all apparently at the same place, and should most likely be considered 
serious enough to warrant knowing about .. maybe doing something about?

cheers, Ian