how to cache DNS lookups (linux/openvpn/firefox)?

[uatavpn 6]

unless there is an important security concern, i'd like to cache DNS lookups but i need help to accomplish this

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​i'm running linux mint with openvpn (not using the Air client) and firefox and am using the DNS servers provided by the AirVPN nodes

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​firefox apparently includes it's own DNS caching mechanism, controlled with ...

network.dnsCacheExpiration [integer, def=60]

network.dnsCacheExpirationGracePeriod [integer, def=60]

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​this can be disabled by setting the first one to '0' and then DNS caching is supposed to fall back to the OS

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​the question is, what is the best way to cache the DNS lookups from the Air servers to avoid the constant lookups - the browser or the OS (or not at all)? i think i might prefer the OS since there is other software in the mix other than just my browser, but given the situation (Air DNS and openvpn), i don't know how to go about it

[zhang888 1066]

First you need to determine where do you want to run your caching resolver.

The most common options are either the router, or your local caching server.

 

If you choose the second option, you have to choose between BIND, ncsd or dnsmasq.

 

Then each one of them has a configurable file which tells the server what to cache and for which period.

Most router firmwares use dnsmasq. This is a very light and easy to configure daemon.

[uatavpn 6]

​sounds like dnsmasq would be preferred - i'm looking at this guide: https://community.linuxmint.com/tutorial/view/489

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​so in /etc/dnsmasq.conf it says to change the listen-address to 127.0.0.1 - however i believe 127.0.1.1 is being used in conjunction with the VPN, so which is the proper address to use?

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​my question is the same for /etc/dhcp3/dhclient.conf and prepend domain-name-servers- 127.0.0.1 or 127.0.1.1?