i have 2 drivers :
lsdev -Cc tape ==> 
rmt0 Available 08-08-00-6,0 LVD SCSI 4mm Tape Drive
rmt1 Available 0A-08-02     Other FC SCSI Tape Drive
rmt2 Available 0A-08-02     Other FC SCSI Tape Drive

so,i stopped the networker daemons (nsr_hutdown -aq);opened the door of my 
library L40 and i puted one tape in the first driver :/dev/rmt1 manually and i 
test the command :
mt -f /dev/rmt1 offline
after that i make the same test withe the driver number 2 /dev/rmt2
conclusion :
no probleme withe the order of drivers,the drivers behavior is corect !!!
so the problem is not the order of drivers ... or mybe this is the cause and i 
don't know how to test it ?

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