When using ssh -D to setup a socks proxy, DNS queries and DNS traffic are not sent through the ssh tunnel. However, with Firefox a config change can be made to send DNS traffic through the ssh tunnel. Here’s how it works!
First, establish an ssh proxy:
$ ssh -D 9000 user@host
Then in Firefox, enable a SOCKS proxy to localhost, port 9000 (or whatever port desired). This will enable all web traffic to go through that ssh tunnel.
Next in order to also send DNS traffic through the proxy, open a Firefox tab and go to about:config
Change the following value to true:
network.proxy.socks_remote_dns