I have two esxi 5.1 hosts with an HA setup connected to vcenter. The guest vm's datastore is located on a SAN. About once a month the esxi2 host drops. I can ping it, I can connect to the host with ssh, and I can go to https://esx2host/; but I cannot connect to it with vcenter or vsphere, nor are the virtual machines available.. I cannot run the shutdown command, it will not work. Once I reboot the server from the server management console or a hard power off, power on, then the HA migration will begin and I can connect to the virtual machines. Once the server comes back on line and esxi finishes loading, the server connects to the SAN and to vCenter again. Then I can begin migrating guests back onto the second host. This creates more down time than is acceptable. I ran extensive hardware diagnostics on the server hardware and looked at the IMM logs and saw nothing stand out from a hardware perspective. Can anyone point me in the right direction as to where I should look to figure out what the issue could be?
Thanks