WRITE(06). CDB: error in /var/log/messages

[Ryan Petty]

Hello,

I am not a new user to FreeBSD, but I am seeing some errors in 
/var/log/messages that I am not familiar with and have had difficulty 
finding a definition and ultimately a resolution.

I have researched the FreeBSD documentation, but my searches lead to 
developer information which does not answer my question (at  least in a 
way I can understand it).

A sample of the errors is found below:

Jan 24 11:03:44 homer /kernel: (da0:ahc0:0:0:0): WRITE(06). CDB: a b a2 
73 8 0
Jan 24 11:03:44 homer /kernel: (da0:ahc0:0:0:0): Deferred Error: MEDIUM 
ERROR info:17f asc:14,1
Jan 24 11:03:44 homer /kernel: (da0:ahc0:0:0:0): Record not found field 
replaceable unit: 1
Jan 24 11:04:12 homer /kernel: (da0:ahc0:0:0:0): WRITE(06). CDB: a 11 
65 df 20 0
Jan 24 11:04:12 homer /kernel: (da0:ahc0:0:0:0): Deferred Error: MEDIUM 
ERROR info:17f asc:14,1
Jan 24 11:04:12 homer /kernel: (da0:ahc0:0:0:0): Record not found field 
replaceable unit: 1
Jan 24 11:05:29 homer /kernel: (da0:ahc0:0:0:0): WRITE(06). CDB: a 0 2 
1f 20 0
Jan 24 11:05:29 homer /kernel: (da0:ahc0:0:0:0): Deferred Error: MEDIUM 
ERROR info:17f asc:14,1
Jan 24 11:05:29 homer /kernel: (da0:ahc0:0:0:0): Record not found field 
replaceable unit: 1

What do these errors mean and how do I fix them--or is this a sign of a 
dead or dying drive or SCSI controller?

Thanks for the help.

Ryan Petty