Since replacing our previous firewall with a Draytek 2927, machine names are no longer contactable, either by ping or by web requests.
We can ping IP addresses. I've manually added a database server using applications, DNS and LAN forwarding an d this works, but I'd rather not have to do this for every device.
The ISP is Andrews and Arnold VDSL PPPoE
The DNS setting in LAN is blank (as this should be managed by the ISP)
How do I fix this so machine names are broadcast over the LAN?

Are you using a Peer-Peer network or Active Directory? What OS on the client PCs?

adampembs wrote:
Since replacing our previous firewall with a Draytek 2927, machine names are no longer contactable, either by ping or by web requests.

It could just be that the IP addresses have changed (assuming the Router also provides DHCP to the LAN) ... maybe it'll get back into line by itself. (Or maybe you've got some hard-coded entries in an LMHosts file)

Was the previous firewall a Draytek, or some other brand that provided some Netbios-related functionality, that the 2927 doesn't? (A WINS server maybe?)

Assuming a single, flat LAN (i.e. no VLANs, or separate IP networks), I can't think of any way that the 2927's LAN could interfere with Netbios name resolution. It should be just working as a simple Ethernet switch...
See: https://www.techrepublic.com/article/how-netbios-name-resolution-really-works/

Can you not just enable the 'DNS Server role' on a Windows server and hand out its IP address via DHCP. Then "Bob would be your uncle" :wink: