We have recently has a leased line installed and i am in the process of migrating all our network services over to the new line from our old ADSL line.
We use a watchguard x510 FW: 11.4.1 we use webblocker for internet filtering
I have a problem with our DNS whereby all at least once a week i get no external dns resolution.
Internal resolution is fine but i cant resolve say www.google.co.uk
some websites seem to work but i have only found one or two.
The dns servers are replicating fine and from looking at the firewall dns resolution is predominatly done by one server.
When the problem occurs i restart the dns server service and it seems to work ok. No entries in the eventvwr which look like they need attention.
I am strugglig to troubleshoot the issue as im not sure where else to look.
Domain is a 2008 functional level.
Your help is appreciated.