At work they are using ForitGate VPN. To be able to work from home I have to use the FortiNetSSLVpnClient. It seems FortiGate is not compatible with any existing other VPN Clients. The forticlient some times crashes and this seem to result in routes not being cleaned up as it should be.
When I am in the office my Ubuntu 12.10 thinks I’m still using VPN and tries to tunnel the connections through the forticlient, which is not running of course. The result is that I get failures for connecting to certain internal domains and servers.
Ping to the servers doens’t work. That gives DNS Lookup failures but performing dnslookup works.
The fix! Flush the dns’s using
sudo /etc/init.d/dns-clean
Update:
Also check that the DNS entries in /etc/resolve.conf are correct. It is possible that the fortinet client did not clean it up as it should be.