> This confusues not only you.
> To resolve that, there must at least one other criteria exist which is not 
> visible at all.

So are there other criterias not visible in the GUI?

I have tried using nsradmin, I found for example:

     type: NSR notification;
                        name: Tape mount request 3;
                     comment: ;
                      action: \
"/usr/bin/mailx -s \"backupserv's tape mount request\" root";
                       event: Media;
                    priority: alert;
                     enabled: ;
 additional email recipients: ;
 
         type: NSR notification;
                         name: Verify Label failed on unload;
                      comment: ;
                       action: \
 "/usr/ucb/mail -s \"Verify Label failed on unload\" root";
                        event: Media;
                     priority: alert;
                      enabled: No;
  additional email recipients: ;

So there is nothing visible from the CLI not really shown in the GUI, except 
maybe for "enabled yes/no".

The question remains, how does it distinguish between different notifications 
if in fact they are all the same (from what we can see).

Those are two notifications mentioned as default notifications in the 
Administrator's guide:

Tape mount request 3
Windows: Sends a request for mounting a backup volume, using a priority of 
Alert, to the
media.log file.
UNIX: Sends an email to root to request that the tape be mounted.

Verify Label failed on unload
Sends an email to root/Administrator: Unable to read the tape label.

They are both of event/prio Media/alert, yet they are about two distinct 
events. I don't get it...

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