1. ESXI concept:
VMware vSphere Hypervisor is the new name of the previous VMware ESXi Single Server or free ESXi (usually "VMware ESXi. The license granted to it only provides vSphere's virtualization hypervisor functionality, but it can also be seamlessly upgraded to a more advanced VMware vSphere version. VMware vSphere has multiple versions and kits designed for customers ranging from small businesses to large businesses.
2. The ESXI version 4.1 installed on the old server is free ESXI, and the new control center VCenter is 5.1. When using VCenter to connect to this host, the following error is reported:
[The licensed version of the host is vSphere 4 Hypervisor. The license version of vCenter Server does not support vSphere 4 Hypervisor]
Error message: An error occurred while assigning a license to the host machine of version 5.1. That is to say, version 4.1 does not accept the license of version 4.1 VC.
Solution: search for the 4.1 Host license. When adding the 5.1 VC host, enter the 4.1 Host license to add it.
A 4.1 License is provided for the test:
HY2J2-83J17-H88M0-KTCQ2-8L02D
How to manage ESXI host in VCenter