Came across the following issue when preparing my hosts for NSX. This issue relates to when the vCenter certificates have been updated. My environment I have configured my VMCA as a subordinate CA. The error reported is below

The problem is ESX Agent Manager fails to log in after the certificates have been updated. If you have updated your certs follow this VMware KB found here

To run this on the appliance connect using SSH and login as root. Start the BASH shell and enter the below

mkdir /certificates

/usr/lib/vmware-vmafd/bin/vecs-cli entry getcert -store vpxd-extension -alias vpxd-extension -output /certificate/vpxd-extension.crt

/usr/lib/vmware-vmafd/bin/vecs-cli entry getkey -store vpxd-extension -alias vpxd-extension -output /certificate/vpxd-extension.key

python /usr/lib/vmware-vpx/scripts/updateExtensionCertInVC.py -e com.vmware.vim.eam -c /certificate/vpxd-extension.crt -k /certificate/vpxd-extension.key -s localhost -u Administrator@vsphere.local

You should now be able to install the host extensions