New user question about DNS resolver
If I am using DNS resolver, does this mean that I don't have to set DNS servers in the general settings? If I don't set the DNS servers for the system, how does pfsense know how to find addresses? Also, is there any improvement in speed by manually entering DNS servers (for example, my ISP DNS servers)?
No you do not need to set any dns if you using the resolver. Its a resolver!! It walks down from roots to the authoritative server for what your looking for and directly asks it for what your wanting vs asking your isp for the record and just getting back the cached entry.
You get your info direct from the horses mouth using the resolver.
Yes in some cases using your isp caching dns can be quicker than resolving something for the first time. If you are having speed issues with the resolver, then I would suggest you just go back to the forwarder and use whatever open/public/isp dns you want to use.
I would really suggest you read up the difference between forwarding and resolving.. I like my info direct even if takes a few ms longer, also using dnssec, etc.
Thanks. One more question - are there any security/privacy implications to using DNS resolver vs an ISP DNS server?
Well in the resolver you can be sure you have dnssec support. With a forwarder would depend if they support it or not, etc.
Your never sure what is in the cache in the forwarder you ask, could be bad. With resolver you know your talking to the authoritative server and getting the info from the horses mouth. Especially if its a dnssec enabled domain.
With the resolver and without forwarders you're not vulnerable to an attack known as cache poisoning where a compromised forwarder serves specially crafted malicious answers to redirect clients of the forwarder to sites that are part of an attack network.