When setting up a Cisco ASA VPN with split DNS for a Windows VPN client, there are a few considerations to keep in mind. Split DNS is a feature used to keep certain DNS requests from traveling across the VPN tunnel, while allowing all other traffic to travel through the tunnel. This is useful for maintaining privacy and security, as well as for improving performance.
When setting up a Cisco ASA VPN with split DNS for a Windows VPN client, there are several steps to follow. First, the ASA needs to be configured to support the split DNS feature. This is done by configuring the ASA to accept the split DNS requests from the VPN clients. Next, the Windows client needs to be configured to use split DNS. This can be done by setting up a custom connection in the VPN client. The custom connection should be configured to use the split DNS feature.
Once the ASA and the Windows client have been configured to use split DNS, the DNS server on the Windows client needs to be configured. This is done by setting up a DNS server on the Windows client that is accessible from the ASA. This server should be configured to allow only DNS requests from the VPN clients.
Finally, the Windows client must be configured to use the DNS server on the ASA. This is done by setting up a DNS suffix in the Windows client. The suffix should be the same as the domain name of the ASA. This will allow the Windows client to send DNS requests to the ASA, while keeping all other traffic in the VPN tunnel.
Using split DNS on a Cisco ASA VPN can be a great way to improve security and performance. It can also help to reduce the amount of traffic going through the VPN tunnel, which can improve performance and reduce bandwidth usage. By following the steps outlined above, an IT admin can easily configure a Cisco ASA VPN with split DNS for a Windows VPN client.