We are using Vcenter 6.0 with 2 esxi 6.0 hosts. Both hosts have identical hardware. Nothing recently has been added in the environment.
One host has a disconnected status and is greyed out in Vcenter. I can ping this disconnected host by IP and DNS name from all network devices except the Vencter and host can not ping each other.
I read documentation posted and checked DNS/firewall and agent communication on port 902 and it is communicating correctly and not blocked.
The only difference between the working host on VCenter and the disconnected host on Vcenter is that the disconnected host has a VLAN which in Vcenter under hosts - network the VLAN name is listed before the VM Newark and I am not sure if Vcenter is trying to use the VLAN IP to communicate with instead of the default LAN?
Both have a DAG storage device and all paths on both hosts show no errors and have active status on all links.
I have looked at the vpxa.log and do not see any error entries, but do see these 2.
2017-04-21T19:10:48.350Z info vpxa[395A7B70] [Originator@6876 sub=VpxaHalResourcePool opID=SWI-4075edcf] GetOverrideFailureCount() = 0MAX_CONSECUTIVE_OVERRIDE_FAILURES = 3
2017-04-21T19:17:07.335Z verbose vpxa[39523B70] [Originator@6876 sub=hostdstats] Set internal stats for VM: 3 (vpxa VM id), 20 (vpxd VM id). Is FT primary? false.