We have a lab which we can access by using a VPN (Cisco ASA and Cisco AnyConnect). This setup has a so-called split DNS configuration, which means that only resources in the lab are accessed through the VPN tunnel. Regular Internet traffic uses my local DSL connection.

At my house I (like most folks) rely on DHCP for providing me with IP address, gateway and DNS servers. My local subnet uses 192.168.10.1 for DNS and 192.168.10.254 is my default gateway. So my clients are in the same subnet as my DNS server (directly-connected).

All these things considered I should be able to browse the Internet while I have a VPN running. Well, that's where you're wrong.