DHCPd using wrong interface

[Dan Egli]

On Tue, Dec 22, 2020 at 07:07:49PM +1100, glenn.satchell at uniq.com.au wrote:
> Hi Dan
> 
> Which bind server is it trying to update? Those updates are sent as 
> unicast packets and are subject to normal routing rules. Perhaps it's 
> trying to update the ISP's DNS server?
> 
> Can you use tcpdump to see what the destination IP address is?

That may be workable. I'm actually away from the machines until much later tonight. The only question I have is how to use tcpdump as I've never used it before. I take it from reading the man page that I just run tcpdump while a machine is obtaining a lease on an IP?

Sorry, I'm still learning a lot.