VMware VCenter5.5 Appliance SSL Certificate enrollment

The Very Quick/Easy and Painless way.

Carefully take a snapshot on VCenter5.5 before certificate enrollment

Copy the your.key your_cert-combined.crt to /root on VCenter5.5 appliance via SFTP

mv yourcert-combined.crt rui.crt
mv your.key pk8.key
openssl rsa -in pk8.key -out rui.key
service vmware-stsd stop
service vmware-vpxd stop
/usr/sbin/vpxdservicecfg certificate change rui.crt rui.key

If the output status is 0 = Success! then

reboot

Reference: http://kb.vmware.com/selfservice