I'm having trouble with a VPN client on Windows that doesn't seem to resolve addresses in the local domain (like name.corp.local) when connected. I've set up a Docker container that runs an OpenConnect VPN server, and the server assigns virtual IPs in the range 10.10.10.0/24. The Docker container uses a standard bridge network, and UFW on the host is managing the routing rules with a NAT rule in place. My configuration for the VPN includes a network and a DNS server, with traffic leaving the container through the host IP 10.102.0.200. The domain controller is set up with both forward and reverse zones, and DNS resolution works fine from the host and within the container. However, from the Windows VPN client, I can ping the domain controller, but DNS resolution fails unless I add entries manually to the hosts file. I'm at a loss for what to try next.
1 Answer
It sounds like your VPN setup might be missing the DNS suffix for your domain. Make sure you include it in your VPN configuration so that the client knows to append it when trying to resolve names. Without that, it won’t resolve the local addresses by default.
I've heard that's often the issue! If you're unsure how to add it, you might want to check the VPN client settings or the documentation for OpenConnect.