Hi, noob question here but I am starting back up my home lab and through ESXi and added my free license but it would not allow me to power up the VM with the error "Failed to power on virtual machine ******. There are insufficient licenses to complete this operation. Click here for more details." The VM successfully started without the license key with the trial version I guess but would not power on with the key added. I believe this worked when I did it last but I could be mistaken and I apologize for my ignorance. Appreciate any help
Ubuntu 18.04 x64
18 GB RAM
1.25 TB Storage
Cisco UCS c210 m2
20 GB RAM
2 Xeon E5620
8 146 GB SAS HDD
When you first install ESXi, the installation is license with a "Trial" license initially, which lasts for 60 days. This has no restrictions, but after 60 days you will no longer be able to control the host, i.e. start VMs, make config changes etc.
I would guess that you started the VM listed in your post whilst the host was operating under its trial license. At some point you changed the license from "Trial" to "Free", which applies some restrictions and removes access to all the vSphere features like HA, FT, etc. but also limits VMs to a maximum of 8 vCPUs. Since your VM was already running it wasn't affected initially, as these limits are only applied on powering up a VM.
It came into effect when you subsequently shut the VM down and then tried to power it on again.
There is quite a useful read about all this here : https://www.altaro.com/vmware/esxi-free/