On Fri, Aug 25, 2017 at 10:12:07PM +0900, Mark Fletcher wrote: > However, now, based on your response I am thinking the AirStation is > just forwarding the DNS queries on to the nameservers it is given in > response to its DHCP query, and not actually caching anything...
Very likely, yes. > would a nameserver need a lot of memory / disk space? The > machine has a 32GB SSD, of which about 15GB is free, and 4GB of RAM, of > which according to top about 1.8GB is free... That is plenty of memory for a caching resolver. Luxury! As a real-world example, <https://cr.yp.to/djbdns/dnscache.html> (which is what I use) uses about 2 MB of RAM in a small-network configuration. It doesn't say so on that page, but the default value of CACHESIZE is 1000000 (a million bytes). So, figure about 1 MB plus however high you set the CACHESIZE variable. I can't speak for other DNS resolvers. BIND in particular may be quite bloated, and would not be my choice for a new setup.
