Maybe You like to enable SNMP on Your VMware ESXI server.
Recently I used some suggestions from this page.
Install the VMware vSphere CLI interface andi issue commands like
vicfg-snmp –server <ESXi_ip> -c <communityname> -p 161 -t <destination_host>@161/<community name>
vicfg-snmp –server <ESXi_ip> -E
or (a bad but working way) just edit the file /etc/vmware/snmp.xml