Kinsei, here is the KB referring what your are looking for. I wish it helps:
By the way i'm having the same issue, i tried restarting the services and it still the same. In the beginning it was working and suddenly it stopped.
The error i got is that if a browse https://<vcenterIP/DNS>:443/sps/sdk it appear "503 Service Unavailable", and my sps service is up.
What is your vcenter HW configuration? Have you tried restarting your vCenter? What vcsa version?
We keep in contact.
Hope i can help you and we can find the issue.
Francisco.-