Tuesday, 21 January 2014

407 Proxy Authentication Required

Recently I installed an Ubuntu box, following my windows configuration, I set my proxy as http://proxyhost:8080
But when I tried to wget something, I got this error:
"407 Proxy Authentication Required"

It turns out the proxy server requires my windows AD username/password. After googling around I found the software Cntlm (http://cntlm.sourceforge.net)
The installation and setup steps are quite straightforward:
  1. Download cntlm_0.92.3_amd64.deb from http://cntlm.sourceforge.net
  2. Installing cntlm
    # dpkg -i cntlm_0.92.3_amd64.deb
  3. Configure /etc/cntlm.conf
    Username        linuxscripter
    Domain          windows-domain
    Proxy           proxyhost:8080
    NoProxy         localhost, 127.0.0.*, 10.*, 192.168.*
    Listen          3128

  4. Generate encrypted password:
    # cntlm -H -M http://proxyhost:8080 -c /etc/cntlm.conf
    You will be prompted for Password, key in your windows AD password, and copy the command output and paste in /etc/cntlm.conf
  5. Restart cntlm service:
    # /etc/init.d/cntlm restart
  6. Set proxy to http://127.0.0.1:3128
My Ubuntu is ready to connect to outside world!