I have used a VPN (cisco on server side I think, and using built in Ubuntu client in network-manager) for years from my Ubuntu (11.04, install all updates) workstation. When I tried to connect on Monday it didn't work and hasn't worked since. The last thing in the log is about LCP timing out.
I tried it with a netbook, it failed, took the netbook to the library, and it worked. So it appears to be something with my network or the ISP. I don't remember changing anything, so... I'm somewhat at a loss to what might have happened.
My computer is hooked up to a router (linksys, years old but has latest firmware) which is connected to the cable modem.
Is there some magical traceroute or something that I can do to find out where it's breaking down?
ps. I tried hooking my computer directly up to the cable modem, but I couldn't get it to work. It made several DHCP requests and then gave up. Tried a static ip which got networking connected but I couldn't get to the internet.
I also checked the log on my router. It showed an outgoing connection to vpn server on port 1723.
Update: The original question was asking for troubleshooting tools, but... FYI: I was able to connect direct to the cable modem and the VPN worked then so... somehow the use of the router was working one day and suddenly stopped working the next? odd...