I have a browser (FF) using proxy, with use this proxy server for all protocols option enabled. How will DNS behave? Will it go through proxy as well?
"use this proxy server for all protocols " probably means all protocols used in the URL
It does not mean every protocol that might be used by the OS in servicing this request
Make sure that your local DNS settings can resolve your proxy server domain,then it will go through the remote proxy server as well.When I use firefox,local dns server can resolve a proxy server domain,but with GFW DNS pollution,I cannot browser twitter.But I can open twitter website when the proxy is on.