I have the same problem.My scenario is VcenterServer STD 5.5.0 u1, I have 3 clusters without problems. In this fourty cluster I can't add a new hosts with esxi 5.5 update 3 (vmware hp version).
"Cannot contact the specified host. The host may not be available on the network, a network configuration problem may exist, or the management services on this host may not be responding"
network: all servers on the same network without FWs.
Vsphere CLI: connect direct to host OK.
Restarts: restart host new, restart vcenter server, no changes.
Update your vCenter Server to the latest release -> 5.5.0 U3b
Just had this exact same issue and thought it was SSL related, but it turns out my vCenter was update 1 and the hosts are now update 3... The other two posters are correct: Upgrading the vCenter server to update 3 fixes this issue.
We had the same error message and issue as well. We could ping the guest and host but they couldn't ping each other. Disconnecting and reconnecting the nic on the vcenter VM fixed our issue.
Its looks like a version incompatibility between Esxi host and Vcenter server. Are they both of the same version ? If not that might be the reason for sure. Please get it checked an update back.
I also have the same error, so anyone can help me fix this error please.
Renalsupport, your answer took care about the issue i had so i would say this is the correct solution, THANK YOU.
I downloaded the latest version of VMware Vcenter 5.5 3d and just run the update and it worked perfectly.
I had the same issue with vCenter 6.5, ESXi running 6.5 was not getting added.
Tried the VMware KB and finally reset of the ESXI management network fix it.