I have pfsense setup within an esxi 6.5 environment, and it was working perfectly fine with no problem at all. Genuinely, an excellent platform for a small enterprise level environment.

As the business was growing, we needed to introduce AD in the office , and I had to pass on DNS, DHCP and ofcourse AD to this Windows 2012 R2 instance. But unfortunately, since I have made this change. I am unable to resolve internal addresses via the hostname.

I am clueless what should I do to have it working. Do I need to dig more into Windows side or is it pfsense or is it both.

Apologies, I am not a pro at networking.

Ping to local addresses work.
Internet and outbound traffic is normal as expected.
I can translate windows host via hostname but cant do it for any other device in the environment.

esxi ip: 192.168.1.1
pfsense ip: 192.168.1.2
windows ip: 192.168.1.5

looking at ifconfig of a random hosts I get this:

ip address : 192.168.1.102  (range defined as 192.168.1.100 - 192.168.1.200)
subnet mask; 255.255.255.0
gateway; 192.168.1.2
dns: 192.168.1.5

Any help be appreciated.