Rules file

Customize the rules file so that the probe can process HTTP POST requests.

By default, the rules to process HTTP POST requests are not enabled. To enable the rules:

  1. Open the rules file (mttrapd.rules) in a text editor and locate the following lines:
    if (exists($snmpreq) && !match($snmpreq,""))
    {
    	# Uncomment the line below to enable rules file for bi-directional
    	# functionality. Specify the path of the rules file if it is not 
    	# in the same directory with this rules file.
    
    	# include "mttrapd.bidir.rules"
    }
    else if( match( @Manager, "ProbeWatch" ) )
  2. Remove the comment marker from the line: # include "mttrapd.bidir.rules".
  3. Save the file and exit from the text editor.

The mttrapd.bidir.rules file supplied in the same directory as the mttrapd.rules file. If the file is moved to a separate directory, specify its full path in the include statement.

Changes to the mttrapd.rules file

With the introduction of the cached host name resolution feature in Release 20 of this probe, several updates have been made to the mttrapd.rules file.

In previous releases, Node (among other tokens) has been used to compose the Identifier event. This release of the mttrapd.rules file has the following changes:

  1. NodeAlias supplants the role of Node in the composition of Identifier.

    When the host name resolution feature is enabled (that is when the NoNameResolution property is set to 0), the Node token for the same trap alert can be amended in runtime either from IP address to host name, or from one host name value to a different host name value. Because of this, Node can no longer be used in the Identifier event, otherwise deduplication will fail. So NodeAlias is used instead in the Identifier event. For example:

    @Identifier = "" + @NodeAlias + "" + @Agent + "" + $generic-trap + "" + $specific-trap + "" + $1 + ""

  2. The Node column in the event list is subject to mandatory update in the mttrapd.rules file when the NoNameResolution property is set to 0:
    if ( int(%NoNameResolution) == 0 )
    {
          update(@Node)
    }

If you currently deploy the SNMP Probe with a custom mttrapd.rules file, you must make similar changes to your custom rules file to enable the event deduplication and to update the Node column.