How can I read the log when I fail with VPN
Whether you choose L2TP over IPSec or PPTP for your settings, the log file is located at:


  /var/log/ppp.log


If you want use terminal to view your log file you can do following:


  vim /var/log/ppp.log       
  
  tail -f /var/log/ppp.log       (if you
  want see end of file)
  
  less /var/log/ppp.log  (if your log
  file was huge and want to see page by
  page)