Virtual servers are perhaps the best technology invention in the past 15 years. Just considering the cost saving and positive impact of doing more with lees, nothing comes close in my opinion. As the virtual server market grew, some server management tool fell behind; SNMP most notably. From thin to non-existent SNMP implementations good solution were hard to find We created a VMware free tool but in ESX 3.5 you had to manually configure the servers by editing the snmpd.conf file. ESXi 3.5 the SNMP agent only had trap capabilities.
The concept of cloud computing along and the very large scale deployments that make the cloud possible forced VMWare to create a centralized and intelligent management center. Wikipedia has a very good graphic depicting the inherent complexity of a vShpere environment. This shows the level of complexity in a cloud environment. As you can see, there really is no room for manual configurations to enable SNMP. vSphere is the cookie cutter that enables the infrastructure, all you have to do is point it back to your SolarWinds Virtualzation Management and Storage Manager.