Hi everybody,
I am having a problem with a Vigor 2955 and a 2830n. They are brand new and with the latest firmware.
2955: v3.3.0
2830: 3.3.6.1db_232201
The problem I am having is that I can't access websites, so I'm guessing this is related with DNS resolution. When it happens I can VPN and access the router, but the end client can't access websites. I can ping, and do get an answer if I ping by IP, but not by name. Restarting the router fixes the issue so from there my concern. Is there anything I need to check on the router related to this issue? I can also attach a backup of the router config if that helps.
Thank you very much in advanced.

DNS resolution should be fine on those since they are just DNS forwarders - make sure that you haven't got UDP flood defense enabled under Firewall - DoS defense, if that gets triggered then it'll cause DNS resolution to fail as it goes over DNS.
Also ideally make sure that both those router's clients are using the router IP for DNS resolution if you haven't got another DNS server, that way it can do DNS forwarding properly