[Nut-upsuser] fsd fails to notify slaves

[dmanye]

hello,

i have an apc smt750i with 3 debian computers connected to it. i want 
one of them act as a master to notify the other two in case the battery 
is about to exhaust.

upsmon in the slaves gets notified when the system changes from main to 
battery and viceversa. the problem i have is that the slaves are not 
notified and shutdown because of losing the connection to the master, 
but not for being notified to shutdown as i expect.

i'm using debian packages. i've tried two scenarios, one with the three 
machines using debian wheezy (nut 2.6.4) and another one with tree 
debian jessie machines (nut 2.7.2). in both cases i get the same log 
error when i force a shutdown with the command 'upsmon -c fsd':

Apr 21 17:45:23 jessie641 upsmon[532]: FSD set on UPS 
smt750i at 10.21.102.241 failed: ERR ACCESS-DENIED
Apr 21 17:45:23 jessie641 upsmon[532]: Executing automatic power-fail 
shutdown
Apr 21 17:45:23 jessie641 upsmon[532]: Auto logout and shutdown proceeding

i think the problem may be the first line. do you know what can be the 
cause?

thanks.