Viewing SCSI errors..

[Jerlique Bahn]

> > I've added a tape drive to my server and the drive only seems to work at
> > 2MBps.  The drive should be doing about 24MBps. The tape is a DELL 110T
> LTO2
> > which runs at about 86Gb/hr.
> >
> > I am trying to diagnose where my problems could lie, and was wondering
> how I
> > could see if there are any errors in the communication between the tape
> and
> > the scsi card (320Mbps). I'm quite confident the speed issue is related
> to
> > the tape drive or the scsi chain.
> >
> > Your suggestions welcomed.
> 
> 
> How did you measure the 2MBps number?

With iostat, eg 

# iostat 5
      tty           amrd0            amrd1              sa0             cpu
 tin tout  KB/t tps  MB/s   KB/t tps  MB/s   KB/t tps  MB/s  us ni sy in id
   0   12 57.81   2  0.13  53.21   6  0.32  31.99  24  0.76   0  0  1  0 99
   0   46  8.00   0  0.00   0.00   0  0.00  32.00  88  2.74   0  0  0  0 100
   0   16  0.00   0  0.00  16.00   0  0.01  32.00  87  2.73   0  0  1  0 99
   0   15  0.00   0  0.00   0.00   0  0.00  32.00  88  2.74   0  0  0  0 100
   0   16  0.00   0  0.00   0.00   0  0.00  32.00  88  2.74   0  0  0  0 99

JB