Skip to main content

“Send SNMPv2 Trap when an alert occurs” feature is turned on and an alert is triggered, but SNMP trap receiver does not receive the trap

Jerry Wu
  • Created:
  • Updated:

Problem:  “Send SNMPv2 Trap when an alert occurs” feature is turned on and an alert is triggered, but SNMP trap receiver does not receive the trap.

 

Symptoms: You see an alert entry in Alerts, but SNMP receiver does not receive the traps.  Alert via email works. 

 

Diagnosis: 

tcpdump can tell us if Stratusphere Hub actually sends out SNMP traps when alerts are triggered.   Logon to Stratusphere Hub’s console directly (https://liquidwarelabs.zendesk.com/entries/25053567-Cannot-logon-as-root-to-the-console-in-Stratusphere-5-5) or via SSH/PuTTY (https://liquidwarelabs.zendesk.com/entries/24782618-How-do-I-Remote-Access-Stratusphere-Appliance-Console-) .  Once you are root, run:

 

tcpdump -n -i br0 port snmptrap

 

If you see an alert is triggered and SNMP trap is recorded, it is a networking and environmental issue.  Otherwise (no trap is sent), it is likely a Stratusphere Hub configuration problem.

 

Possible Resolution(s): 

Stratusphere Hub needs four settings configured properly to send out SNMP traps:

  1. “Send SNMPv2 Trap when an alert occurs” option is on
  2. SNMP Trap Destination set
  3. SNMP Community String set
  4. Stratusphere Hub’s hostname is resolvable.

Usually the setting 1 and 2 are correctly.  Setting 3 “SNMP Community String” however is frequently omitted.  If you do not have a defined community string in your environment, you can put in “public” here.

 snmp_setting.png

Stratusphere also checks its own hostname and see if it is resolvable before it sends out a SNMP trap.  Your DNS server needs to have an address record for Stratusphere Hub, and Stratusphere Hub has to be able to resolve it.  You can verify that by either pinging Stratusphere Hub’s hostname, or run nslookup.  If you cannot resolve the hostname, first try adding an address record on your DNS server.  If you cannot add an address record to your DNS server, you will need to add your hostname to your hosts file so it will resolve to 127.0.0.1:

 

vi /etc/hosts

and append the hostname in 127.0.0.1 line (like the screenshot below). 

 hosts.png

Enter ‘:wq!’ to write the changes and quit.

 

Product: Stratusphere UX 

Product Version: 5.0 and above

Expires on: 365 days from publish date

Updated: Febuary 27, 2014

Related articles