Hello!
%i is a unique identifier of the event's source object (usually node). If you plan to monitor only one service per node with these events, then using just %i is ok, but if you monitor more then one service running on same node and generate same events for diferent services, than you have to distinguish alarms nnot only by node id, but also by service. %3 and %5 is event-specific parameters, number 3 and 5 respectively. For events generated when threshold condition becomes true, parameters are following:
1) Parameter name
2) Item description
3) Threshold value
4) Actual value
5) Data collection item ID
6) Instance
For events generated when threshold condition returns to false, parameters are following:
1) Parameter name
2) Item description
3) Data collection item ID
4) Instance
So in my example I construct alarm key from node id and DCI id.
You can find list of parameters for any predefined event by opening Control Panel -> Events -> Edit appropriate event record and looking at the description field.
All possible macros for event processing policy can be found in NetXMS user manual or here: https://www.netxms.org/documentation/macros.shtml
Best regards,
Victor
%i is a unique identifier of the event's source object (usually node). If you plan to monitor only one service per node with these events, then using just %i is ok, but if you monitor more then one service running on same node and generate same events for diferent services, than you have to distinguish alarms nnot only by node id, but also by service. %3 and %5 is event-specific parameters, number 3 and 5 respectively. For events generated when threshold condition becomes true, parameters are following:
1) Parameter name
2) Item description
3) Threshold value
4) Actual value
5) Data collection item ID
6) Instance
For events generated when threshold condition returns to false, parameters are following:
1) Parameter name
2) Item description
3) Data collection item ID
4) Instance
So in my example I construct alarm key from node id and DCI id.
You can find list of parameters for any predefined event by opening Control Panel -> Events -> Edit appropriate event record and looking at the description field.
All possible macros for event processing policy can be found in NetXMS user manual or here: https://www.netxms.org/documentation/macros.shtml
Best regards,
Victor
В 0.2.21 будет? 
The really needed steps is 2 and 3, and -c option is needed. This is because in 0.2.20 changes syntax of netxmsd.exe command line, to be in common style with agent and other tools.