I searched a long time to set the snmp settings on our ESXI 5.5 hosts with the vSphere webclient. NO CHANCE!
I found nothing to set the community with the vSphere web client. But i found many article where people described how to configure the snmp settings through cli. The following commands have to run within a console session on your host:
esxcli system snmp set –communities public
esxcli system snmp set –enable true
esxcli system snmp set –syscontact=“firstname.lastname@example.org“
esxcli system snmp set –syslocation=“Street, postcode, city“
esxcli network firewall ruleset set –ruleset-id snmp –allowed-all true
esxcli network firewall ruleset set –ruleset-id snmp –enabled true
You have to customize the bold strings with your own values. After the restart of the snmpd you can monitor the host.
By the way we use Observium to monitor our hosts, server and network. Take a look!