For example if I run 'ipconfig /all' on this machine, WinXP home set to get it's details via dhcp from pfSense:
C:\Documents and Settings\Steve>ipconfig /all
Windows IP Configuration
Host Name . . . . . . . . . . . . : NewTuring
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Mixed
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : fire.box
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : fire.box
Description . . . . . . . . . . . : Realtek RTL8139/810X
Physical Address. . . . . . . . . : 00-30-1B-AB-18-C3
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.2.10
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.2.1
DHCP Server . . . . . . . . . . . : 192.168.2.1
DNS Servers . . . . . . . . . . . : 192.168.2.1
Lease Obtained. . . . . . . . . . : 16 June 2013 11:16:05
Lease Expires . . . . . . . . . . : 16 June 2013 13:16:05
I am then able to ping other machines by their hostname:
C:\Documents and Settings\Steve>ping NewBabbage
Pinging NewBabbage.fire.box [192.168.2.2] with 32 bytes of data:
Reply from 192.168.2.2: bytes=32 time<1ms TTL=128
Reply from 192.168.2.2: bytes=32 time<1ms TTL=128
Reply from 192.168.2.2: bytes=32 time<1ms TTL=128
Reply from 192.168.2.2: bytes=32 time<1ms TTL=128
Ping statistics for 192.168.2.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
This works even though 'fire.box' is not a real domain, or at least it's not my domain.
Interestingly this works even though I don't have 'Register DHCP leases in DNS forwarder' set in pfSense. :-\
Steve