How to validate if SNMP traps are being sent to the remote SNMP server from the NSX Manager or NSX Edge

Products

• VMware NSX

Issue/Introduction

SNMP traps are configured from the NSX Node Profile section, utilizing either SNMP v2c or v3.

Environment

VMware NSX

Resolution

To verify whether SNMP traps are being sent, access the NSX Manager using the root user. The same steps can followed to check on the NSX edge.

Run the following command to check if SNMP is enabled:

vicfg-snmp -s

Sample Output:

root@nsx-mngr:~# vicfg-snmp -s
Current SNMP agent setting
Enabled                 : true
UDP port                : 161
V1/V2c Communities      :
V2c Notification targets : <snmp-remote_server-ip-fqdn>@162 <Community String>
Notification filter oids:
V3 Notification targets :
Contact                 :
Location                :
Engine ID               : 80001adc808632b24ee050f36800000000
Auth Protocol           : usmHMACSHAAuthProtocol
Priv Protocol           : usmAESCfb128PrivProtocol
V3 Users                :
Log level               : warning
Process ID              : 2989962
INFO: listing complete.
root@nsx-mngr~#

To send a test trap, run the following command:

vicfg-snmp -T

Sample Output:

root@nsx-mngr:~# vicfg-snmp -T
message                      : A warmStart notification was sent to 1 target.
success                      : True
root@nsx-mngr:~#

The following tcpdump command can be used to verify whether SNMP traffic is being sent from the NSX Manager on port 162:

root@nsx-mngr:~# tcpdump -i eth0 port 162

Sample Output:

root@nsx-mngr:~# tcpdump -i eth0 port 162
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
11:06:50.631076 IP <nsx-manager-fqdn>.56660 > controlcenter.x.x.x.snmp-trap:  C="xxx" V2Trap(82)  system.sysUpTime.0=44070049 S:1.1.4.1.0=S:1.1.5.2 S:1.1.4.3.0=E:6876.4.9

The following logs can also be reviewed to further verify whether the traps are being sent:

Sample Output:

root@nsx-mngr:~# tail -f /var/log/syslog | grep -i snmp
2025-10-23T11:31:45.540Z nsx-manager-fqdn snmpd 709732 - -  23:Sending warmStart notification at operator request

Note: Ensure SNMP port 162 is forwarded between the NSX Manager and NSX Edge nodes to the destination SNMP server.

Additional Information

Please review the “Configure a Node Profile” section in the NSX Administration Guide for instructions on configuring SNMP using node profiles.