There is a DNS cache in Firefox (aside from what is potentially installed in your operating system, like nscd), but it's by default 3 minutes in Firefox 3.5 (1 minute before that).
To change it, go to about:config, create the preference network.dnsCacheExpiration, default is 180 seconds. There's also a total number of entries, network.dnsCacheEntries, default 400.
There is a DNS cache in Firefox (aside from what is potentially installed in your operating system, like nscd), but it's by default 3 minutes in Firefox 3.5 (1 minute before that).
To change it, go to about:config, create the preference network. dnsCacheExpirat ion, default is 180 seconds. There's also a total number of entries, network. dnsCacheEntries , default 400.