Cannot ping ESX hosts by hostname

I have a 6.5 lab I am setting up, and am running into problems. I am hoping it is something simple stupid I am missing, as everything works as expected in my 6.0 lab. Basically I set up four ESXi 6.5 hosts, set up static IP addresses and reverse lookup, and joined to the domain. From the ESXi host I can ping the domain controller, and resolve the FQDN of the host itself. From the DCs however, I can only ping by IP, I cannot resolve hostname. I have cleared DNS cache, restarted management on the ESXi host, etc. Also, if I connect to the host via Putty I can resolve the hostname of the DC, as well as every other ESXi host by name. I cannot think of why I can ping by IP but not resolve by name. Any suggestions are welcome.