Hi, I am trying to moniter the modification of a file (passwd1) , I created an item with the key : vfs.file.cksum[/etc/passwd1] and an active agent ,the trigger's expression is this :{dx2300:vfs.file.cksum[/etc/passwd1].abschange(0)}<0 .but the server won't display any changes , no data in the graph nor events , the item doesn't appear in the latest data as well 
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what might be the problem ?
!!!what might be the problem ?