I've got a vSphere 5.5 Essentials Kit; One of the hosts, a Dell R410, is running vSphere 5.5 and as of yesterday it is unresponsive to any of the management tools. I've tried the following:
Web interface: Down
SSH Port: Connection Timeout
vCenter says disconnected
vSphere Client: An unkown error occured. (The client could not send a complete request to the server. (The underlying connection was closed: An unexpected error occured on a send.))
Local terminal: I tried to log in (entered my credentials), but then the login panel locked. Unresponsive to keyboard input.
All my virtual machines are still running and i don't see any other way out than to shut down all vm's remotely using ssh/rdp and than hard reset the server, but that's my last option.
Any suggestions on how to 'revive' my management interfaces?
You'll probably require a reboot. My assumption is that this is a case of local (boot) disk failure; either a lock-up of the array or the internal SDHC cards you may have used to boot the system.
Can you tell us how ESXi was installed on each host? Local disk? USB or SD card?