If you want to monitor the state of your VMWare ESXi servers in your monitoring system (ZABBIX,NAGIOS,OBSERVIUM,PRTG,...), you must configure SNMP agent on your hosts.
In this article we’ll show how to enable and configure SNMP in VMWare ESXi 5.5-6.X-7.X.
In ESXi, there is a built-in SNMP agent that can send and receive SNMP requests and traps.
You can enable and configure an SNMP agent on ESXi hosts using CLI via ssh, but not through the vSphere client GUI.
Remember : enable ssh on esxi host before to proceed
You can use ssh client like putty (you can download at this link)
When you are connect to ssh console put this command
Set Communities >
esxcli system snmp set --communities public
Enable SNMP >
esxcli system snmp set --enable true
Enable Firewall ruleset >
esxcli network firewall ruleset set --ruleset-id snmp --allowed-all true
esxcli network firewall ruleset set --ruleset-id snmp --enabled true
Restart service ->
/etc/init.d/snmpd restart