When connecting to our VPN using Cisco Anyconnect I am losing internet and DNS. When the pc is disconnected from Anyconnect the internet connection returns. I have tried to force the DNS for the Cisco connection to our internal DNS server but there is no change. Any ideas?

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Check with your VPN administrator. Generally with most VPN client software, you have the ability to enable or disable split tunneling. The difference is that when split tunneling is enabled, you can surf the internet and access other hosts on your network while connected to the VPN solution. When split tunneling is disabled, all packets will be sent down the VPN tunnel to your corporate network.

In your case, the traffic that is trying to make its way out to the internet may be filtered by a proxy server or firewall. For example, if this is split-tunnel disabled, and you have a proxy server on your corporate network, you would have to configure your browser to use the proxy server while you are connected to your VPN server.

I'm only speculating, its best if you check with your VPN admin.

We do not utilitze a proxy server. If we use Cisco VPN Client 3.x it handles all the traffic for both internet and for network without splitting. What would be different with Anyconnect?

Check the routing on both the IPsec client and the anyconnect client. It's easy to see if split tunnels are used. A route of 0.0.0.0 means tunnel everything, any other route would only tunnel the matching traffic.

Also "I lose internet and dns" do you mean that you can send traffic out to the internet like a 'ping 4.2.2.2' or that you just can't browse websites indicating that DNS is not working. Cisco VPNs allow the admin to override your DNS settings such as pushing the company DNS while you are connected. While on VPN, run an nslookup. Do you get a dns server? is it internal or external? Enter www.google.com or something and does it resolve? If it is internal, switch to external with 'SERVER 8.8.8.8' and run the same lookup. What do you get here?

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