FVS114 log question

I have successfully run an FSV114, firmware V1.1_15, firewall router for many years. Recently I am seeing intermittent, mysterious DNS failure which I am trying to diagnose.

I have enabled 'All Incoming TCP/UDP/ICMP traffic' in the hope of verifying DNS responses.

WireShark on a network machine sees responses, but the router logs show only [Drop] incoming of any protocol.

Is this a feature or a bug?

Is it time for me to update my router for something more capable.

Has any Netgear router capability to  mirror the WAN port?

Thanks