Conference azur::mcc

4212.0. "exceptions not clearing revisited" by ANOSWS::COMFORT (Cold iron shackle, ball & chain) Tue Dec 08 1992 11:33

    
    Hi,
    
    I would like to present my observation on the problem of exceptions
    not clearing after a valid evaluation has been made.  It has been
    noted that this appears to be an intermittent problem.  I believe
    the situation is as follows and would be interested in comments
    from enginneering and anyone else that may be interested.
    
    It appears that notification exceptions that do not clear ONLY occur
    when the entity in question is not reachable.  Ie. no link is able
    to be setup.  For example I run the following rule to test a NODE4
    entity:
    
    	Create mcc 0 alarms rule mon_v01 -
    	expression=(node4 v01 state = off, at every 00:03:00),-
    	perceived severity=critical
    	exception handler=some_mail_procedure,-
    	queue=mcc$batch,-
    	in domain na.domains.um

    I also then retarget the exception so as to intercept the indeterminate
    severity generated by an exception and change it to critical.
    
    If this alarm evaluates with:
    
    "node not currently accessible" due to lack of communication, then the
    alarm will never clear even when the rule is successfully evaluated
    false at a later time. 
    
    If the alarm evaluates with something like:
    
    "Node terminated link before link confirmation" or "Insufficient
    resources at target entity", then the rule will clear upon the next
    valid evaluation. 
    
    I have also seen this behaviour with LanBridges.  Ie., if the error
    is:
    
    "Cannot communicate with target", then the rule never clears,
    
    If the error is:
    
    "Communication with target has been interrupted", then the rule
    clears on the next valid evaluation.
    
    The failure of a non-communication based exception to clear is present
    both in the iconic map and the notification window.
    
    Is this the appropriate behaviour?  If this is in accordance with
    the design of the code, then I would like to request a change in
    the philosophy of evaluating and clearing exception conditions.
    Otherwise, I would like to address this as a bug and obtain a fix
    as soon as possible as this is negatively impacting the customer
    site at which I am resident.
    
    Thank you and regards,
    
    Dave Comfort
          

    
    oh well, the notification that I had been tracking all day just
    failed to clear after 54 exception evaluations.  I guess I jumped
    the gun a little.
    
    Dave