This seems to be License issue for me. vSphere licenses are per CPU basis and this could be the reason that you are only able to see 4 CPU in host.
Please read below article and check your license,
This Intel CPU have 8C/16T each. If ESXi only recognice 1C/2T each than something goes wrong at the very first
Please can you check the BIOS of your Server if all Cores are enabled? As a long time Dell user i know that you can reduce the number of Cores within the BIOS for "licensing" reasons to please check the BIOS first.
What ever your ESXi version is you should see 2x 8C/16T = 32 logical CPUs in the summary. Yes, also with the free ESXi Hypervisor you should see this.
Thanks. below is my license. doesn't my license support it?
VMware vSphere 6 Enterprise Plus
Expiration date: Never
Unlimited virtual SMP
H.264 for Remote Console Connections
vCenter agent for VMware host
vSphere Data Protection
Hot-Pluggable virtual HW
vSphere Storage vMotion
Shared Smart Card Reader
vSphere FT (up to 8 virtual CPUs)
APIs for Storage Awareness
Storage-Policy Based Management
vSphere Storage APIs for Array Integration
Remote virtual Serial Port Concentrator
MPIO / Third-Party Multi-Pathing
Big Data Extensions
vSphere Distributed Switch
vSphere Host Profiles
vSphere Auto Deploy
vSphere Storage I/O Control
Direct Path vMotion
vSphere Storage DRS
vSphere vMotion Metro
vSphere View Accelerator
vSphere App HA
vSphere Flash Read Cache
Cross Virtual Center vMotion
vSphere Proactive HA
vSphere VM Encryption
vSphere Encrypted vMotion
vSphere Predictive DRS
Go to the License tab and check how many CPU's it shows there.
Is this server manage from vCenter server??
Can you login to the MyVMware portal and check the license details.
This this is managed from vCenter. This screenshot is from vcenter. this my own server.
This CANT BE a license problem.
Thanks. what do you think the problem is?
I have already written above.
About licensing. I deal with VMware lics for more than 11 years and i cant remember if there ever was a lic/method around which makes happen what you currently see.
Does the Hypervisor see the correct amount of CPUs?