I have a server which acts as a DNS server for our LAN. All our internal
servers have A records on it using a .local domain and it forwards all
other requests out to the root servers using the in built list provided
with BIND. All clients on the LAN have this machine set as their only
DNS server.
It has worked fine for 6 years under Wheezy but I have just upgraded it
to Stretch. I did an upgrade to Jessie first, rebooted checked
everything was OK, and then immediately upgraded to Stretch.
Since then we keep getting intermittent DNS lookup failures for various
domains on the internet, which will typically work if you click the
refresh button in the browser a few times.
BIND seems to just log to syslog/systemd it doesnt appear to be
configured to use its own log. If I run journalctl -xe | grep "named" I
can get the log entries but none of them relate to the failed DNS
lookup. If I do it immediately after a failure has occured nothing is
logged so Im at a bit of a loss to work out what might be wrong.
Does anyone have any ideas please?
Thanks
Andrew
PS I should add that as far as I can tell it has never had a problem
with resolving our internal .local domain it just seems to be real
internet domains its having issues with.