Yup, not-too-long-ago we setup OpenVPN at work with split tunneling which required DNS to work correctly. Windows worked out of the box (except for a small pool

Yup, not-too-long-ago we setup OpenVPN at work with split tunneling which required DNS to work correctly. Windows worked out of the box (except for a small pool of users who had their DNS manually set which was a checkbox fix). macOS was more irritating because OpenVPN didn't native support the DNS API and it turned out the defacto way was Tunnelblick third party software. Linux... Absolute nightmare. Every system had a slightly different DNS stack and trying to get queries to route over the VPN interface was an acrobatic exercise in docs navigation and trial and error. Ultimately, newer desktops with systemd-resolved were the easiest systemd-resolved supporting DNSSEC is also a big win!