https://forum.openwrt.org/viewtopic.php?id=14710
the details of his question can be ignored... he is using a tun vpn.
He wanted to join Active Directory over his vpn.
stickdeoderant wrote If your OpenVPN tunnel assigns your Active Directory DNS server via DHCP you should not have a problem.
How will it lookup via LDAP on your domain without DNS?
If you use DHCP built into OpenVPN you can try this:
push "dhcp-option DNS x.x.x.x"
It works for me!
I don't even need WINS.