Intermittent WAN issues caused by pfSense DHCP Clients?
Due to some maintenance taking place on our Windows systems over the next few days, I have temporarily moved DHCP to pfSense so that people who are around can get internet access.
After having done this all of our clients are receiving DHCP leases form pfSense as expected. However, when any of these clients navigate to a particularly intensive page (i've been using speedtest.net for testing purposes and attempting to start the test), the latency on the WAN gateway increases, pfSense reports the gateway status as "Latency", then "Offline", and the connection goes down for as long as the page sits loading on the device. The page never actually loads, and therefore the connection is down for everyone for as long as the browser tab is left open attempting to load the page.
Before I moved DHCP over from the Windows DHCP server to pfSense all worked well. Currently, any device that I have manually assign an IP address to works fine (unless a dynamic device has taken down the connection!), can run speed tests and navigate to any page without bringing down the whole network.
I have tested the internet connection by directly connecting to the ISP's router (currently in Bridged mode). Even when the latency issues are showing on pfSense and affecting all devices behind it, a direct connection to the router gets a perfect connection so I do not suspect anything past pfSense itself.
It's not too much of a problem, I expect that our normal Windows services can be brought back up over the next few days, i'd just like to get to the bottom of it. Enabling DHCP on pfSense and having users at least get internet access during a maintenance period is something i'd like the option of being able to do into the future.
Are you using unbound as DNS resolver ?
If so DON'T tick this
Will make unbound restart (DNS outage) , for each dhcp renew
@bingo600 Thanks Bingo,
After changing that setting all seems to be working.
Thanks very much for your help,