Wanda P. was a *huge* help with the last round of difficulties I had, but now 
I've run across a few more.
 
I've got 9 dual-connected fiber-attached 3592 tape drives going into this 
library. Sometimes the tape drives behave as advertised, but sometimes the same 
drive(s) will give me
 
ANR8311E An I/O error occurred while accessing drive DRIVE04 (mt3.0.0.4) for 
SETMODE operation, errno = 170.  (SESSION: 4, PROCESS: 3)
 
followed by
 
ANR9999D mmsflag.c(8330): ThreadId<32> Could not determine the media type of 
media O00237 in drive DRIVE04 (mt3.0.0.4). (SESSION: 4, PROCESS: 3)
 
But then the next thing I do with the drive works. It's almost as if TSM uses 
both fiber paths during an operation, causing confusion about whom is doing 
which.
 
I'm about to call Tivoli support, but I thought I'd throw this out to the list 
before I do. Anyone seen anything like this?
 
--
Mark Stapleton (mark.s AT evolvingsol DOT com)
Senior consultant