option dhcp-option DNS

push "dhcp-option DNS 10.10.0.1"

Explanation of `push "dhcp-option DNS 10.10.0.1"`

This configuration directive is typically found in the OpenVPN server’s configuration file. Its purpose is to instruct the OpenVPN server to send specific network configuration details to the connecting clients.

Components

Part	Meaning
`push`	This command tells the server to “push” the enclosed configuration string to the client. This is how the server dynamically configures the client’s network settings.
`"dhcp-option DNS ..."`	This is the specific directive being pushed. It tells the client’s operating system (or the OpenVPN client software) to set the DNS server that will be used while the VPN connection is active.
`10.10.0.1`	This is the IP address of the DNS server that the client should use. This IP address is usually an internal IP address of a device on the VPN server’s network (often the VPN server itself or a local router/DNS resolver).

Function

When a client connects to the OpenVPN server, the server sends this line to the client. The client software then attempts to configure the operating system to use 10.10.0.1 as the primary DNS server for requests going over the VPN tunnel.

This is critical because it ensures:

Internal Host Resolution: Clients can resolve internal hostnames (e.g., file server names) using the organization’s private DNS server.
Security/Control: All DNS lookups are routed through a trusted DNS server, which can be important for security or filtering.

In summary: The server is forcing the VPN client to use 10.10.0.1 for all DNS lookups while connected to the VPN.