There is a new release (Kaseya Network Monitor 4.1) available for download on the Kaseya download page that has both VMWare hardware monitoring via CIM / SMASH and performance monitoring via the VI API.
For sure you have to monitor your ESXi from other server, not ESXi itself, as it is minited environment. There are couple of VMWare APIs you can use to query ESXi data from 3rd server, like perl, .NET, java etc... Then the data you would push to your monitoring system.
There is a new release (Kaseya Network Monitor 4.1) available for download on the Kaseya download page that has both VMWare hardware monitoring via CIM / SMASH and performance monitoring via the VI API.
This should help:
http://blog.kaseya.com/blog/2012/03/23/how-to-monitor-vmware-using-kaseya-network-monitor-4-1/
You'll need the latest build of KNM 4.1, downloadable from:
http://www.kaseya.com/support/Downloads.aspx
For sure you have to monitor your ESXi from other server, not ESXi itself, as it is minited environment. There are couple of VMWare APIs you can use to query ESXi data from 3rd server, like perl, .NET, java etc... Then the data you would push to your monitoring system.