Re: nftables firewall question: matching udp in ipv6

[Ralph Aichinger <ra@h5.or.at>]

On Fri, Jan 12, 2024 at 05:26:57PM +0000, Michael Kjörling wrote:
> My suggestion would be to insert a "udp log" rule. (Pretty sure you
> only need "udp", not "meta l4proto udp".)
  
Thanks,  I will try that. Yes "meta l4proto udp" might be cargo 
cult configuration ;)

> That will give you a firehose of information which will include ports,
> interfaces and other relevant information. You can then narrow it down
> until it logs the traffic you want to accept, at which point you can
> change the "log" action into an "accept" action.
> 
> Note that forwarding and filtering can interact in non-intuitive ways.
> You may need to add corresponding log rules to each relevant chain,
> maybe with a prefix to tell them apart.
  
Thanks a lot!

Ralph