DNS delay on first lookup, Ubuntu 19.10 but not earlier versions

[Colin Law]

On Tue, 31 Mar 2020 at 21:28, Chris Green <cl at isbd.net> wrote:
>
> I have a small home LAN with dnsmasq running on a Raspberry Pi to
> provide DHCP and DNS services.  I have two systems running xubuntu
> 19.10 and on these systems I see a 5 second delay the *first* time I
> look up the address of a local host.  Subsequent lookups are fast but
> if the system is idle for a long time (I haven't quite fathomed out
> how long) I see the 5 second delay again.

Do you see anything relevant in syslog at this time?
I think I have seen something like this before.  I have pushed the
problem into my subconscious and hope that when I wake up in the
morning the memory will be recalled.  Or maybe not .....

Colin