On 30/10/2023 20:04, Timothy M Butterworth wrote:
sudo less /etc/resolv.conf domain home.arpa search home.arpa nameserver 8.8.8.8 nameserver 8.8.4.4
I do not see "# Generated by NetworkManager" here.
    nmcli connection
    nmcli device
    NetworkManager --print-config
    ls -l /etc/resolv.conf
    lsattr /etc/resolv.conf
As to /etc/dhcp/dhclient.conf and /etc/network/interfaces, I may be 
wrong, but perhaps independent instances for IPv4 and IPv6 may be 
running (if actual connection is managed through ifupdown)