The purpose of this article is to outline steps to easily deploy a trap listener in your infrastructure to drive SNMP trap alerts into Uptime Infrastructure Monitor. Although the article utilizes snmptrapd provided by Net-SNMP to receive SNMP traps and execute scripts, one can use any SNMP trap receiver as long as it can execute scripts when traps are received. The steps provided in this article were applied to a Windows server. Identical steps can be applied to a Linux server running Uptime Infrastructure Monitor. Contact Uptime Support at uptime-support@idera.com if you have any issues.

Net-SNMP is an SNMP application suite supported on numerous platforms including Windows and Linux (the two platforms the Uptime Infrastructure Monitor Monitoring Station is supported on). Here is a brief summary of what happens when an SNMP trap is sent:

  • the SNMP-enabled device sends an SNMP trap to the snmptrapd service
  • snmptrapd compares the trap to the list of filters in the snmptrapd.conf file
  • when the trap matches the uptime filter, the trap_to_ext_event.pl perl script is executed
  • trap_to_ext_event.pl calls the Uptime Infrastructure Monitor API to update the status of the External Check monitor associated with the device
  • if an Alert Profile is associated with the monitor, an alert notification is sent out

Below is a diagram depicting the process: 

Install Net-SNMP and Perl

  1. Download Net-SNMP from https://sourceforge.net/projects/net-snmp/files/net-snmp%20binaries/5.6.1.1-binaries/net-snmp-5.6.1.1-1.x86.exe/download.
  2. Download Strawberry Perl from http://strawberryperl.com/download/5.20.1.1/strawberry-perl-5.20.1.1-64bit.msi.
  3. Execute the Net-SNMP installer and accept the defaults.
  4. Execute the Strawberry Perl installer and accept the defaults

Create a snmptrapd configuration file and Perl script

  1. Create a new file called snmptrapd.conf in the C:\usr\etc\snmp directory with contents similar to the following. Note that "public" on the first line is the SNMP community string. Feel free to change accordingly, and the path to UIM on the second line should be changed accordingly.
    authCommunity log,execute,net public
traphandle default C:\Strawberry\perl\bin\perl.exe "C:\Program Files\uptime software\uptime\scripts\snmp- trap-script\trap_to_ext_event.pl"
  2. In the Start menu, select the Net-SNMP folder, right click Register Trap Service and choose Run As Administrator.
  3. Start the "Net-SNMP Trap Handler" service.
  4. Create the directory "C:\Program Files\uptime software\uptime\scripts\snmp-trap-script".
  5. Download and copy this file, trap_to_ext_event.pl, to the directory mentioned in the previous step.

This approach assumes that your SNMP trap service monitors all have the same name, "SNMP Trap (member)", and are managed via a Service Group.

There are two logs that are created with this solution, one when traps are received by the Net-SNMP Trap Handler service and another when the trap is sent into Uptime Infrastructure Monitor by the perl script. This helps to narrow down an issue if one arises. 

UIM configuration

Create a new monitor called SNMP Trap and assign it to a service group, so that it can be applied to numerous Elements in UIM.

To create a new monitor and assign it to a service group

  1. Create a service group for your devices that will send SNMP traps to UIM.
    1. Click Services.
    2. Click Add Service Group.
    3. Select Regular from the dropdown list, and then click Continue.
    4. Type SNMP Trap Group as the name for the service group and, optionally, a description for the group
    5. In the Available Element Groups and Available Elements lists, choose the element groups and elements for which you want to have SNMP trap monitors created.
    6. Click Finish and close the dialogue window
  2. Create an external check monitor and assign it to the SNMP Trap Group service group.
    1. Click Services.
    2. Click Add Service Monitor.
    3. Select External Check from the list of available service monitors, and then click Continue.
    4. Type SNMP Trap as the service name
    5. Select the Service Group radio button, and then choose SNMP Trap Group from the dropdown list.
    6. Choose an Alert Profile to have alert messages sent to the appropriate users.
    7. Click Finish.

Now when traps are received by the Net-SNMP snmptrapd service, the appropriate "SNMP Trap (member)" service monitor will be set to CRIT and an alert will be sent out. When the status is acknowledged in the Uptime Infrastructure Monitor UI (click the ACK button), the status will be set back to OK.

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