alert-mail track number

Hi !

.. only for understanding ..

What's the meaning of the track alert-mail-number in the subject ?

e.g

 Hobbit [698912] scotty:conn CRITICAL (RED)

and e.g 

some alerts have got a zero [0] and still got that only didn't count up ...

 
 Hobbit [0] sc-node-2:cluster CRITICAL (RED)
 
... and how i could start from zero for all host/test (?) again ..


Cheers,

       Martin 
Martin Flemming
DESY / IT          office : Building 2b / 008a
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