On Oct 25, 2012, at 8:42 PM, Frank Swasey <Frank.Swasey AT uvm DOT edu> wrote:

> Today at 11:31pm, Davina Treiber wrote:
> 
>> On 25/10/12 19:48, Yaron Zabary wrote:
>>>  That's the relevant part from the res file. Just shutdown Networker
>>> and edit the res file to point at the right by-id device.
>>> 
>>> control port: /dev/tape/by-id/scsi-200900de794120009;
>> 
>> There's no need to shutdown NetWorker or edit res files. The control
>> port is a field you can modify.
> 

Two final notes...

1) I tried to update the control port while the library was in use and NMC told 
me I had to disable the library before I could change the control port.  
Perhaps that has changed in 8.0, but I'm still running 7.6.4 in production.

2) I spent some time messing about with udev rules and came up with the 
following so I can change the control port to /dev/library0:

# type 8 devices are "Medium Changers"
SUBSYSTEM=="scsi_generic", SUBSYSTEMS=="scsi", ATTRS{type}=="8", 
ENV{ID_WWN}=="", IMPORT{program}="scsi_id --sg-version=3 --export --whitelisted 
-d $tempnode"
SUBSYSTEM=="scsi_generic", SUBSYSTEMS=="scsi", ATTRS{type}=="8", 
ENV{ID_WWN}=="0x500084f0006bbf70", SYMLINK+="library0"

I added those rules to the top of my 20-local.rules file.

-- Frank