We recently upgraded to Vcenter 5.1 and built a new ESXi 5.1 host. Today was the first day we tried to create a VM on the new host and we ran into an issue with the console being unable to connect to port 902 on the host.
I then noticed that I couldn't connect to any open ports on the host from my workstation (80, 443, 22, 902) but could from the vcenter server. As far as I can tell there are no IP restrictions in place on the firewall on the ESXi host. When doing a port scan (nmap) from my workstation the ports show as open but when I attempt to connect I'm immediately disconnected. I can't figure out what the deal is.
As I was typing this post the vcenter server sent out an alert that the host went down. I can no longer connect from the vcenter server either. Port scans show the ports as open, I can ping the mgmt address. Quite confused.