mikrotic openvpn client: why TLS auth needs user/password?

Hi, guys. Following https://wiki.mikrotik.com/wiki/OpenVPN#Client_configuration to configure openvpn clien interface we need to pass some user/password on the command line. Yet we use certificates authentification, so no user/password is required. Could somebody explain why user/password are required?

It’s probably to go along with RouterOS OpenVPN server, because it requires user/password. If your other server doesn’t and wants only certificates, just enter anything as username for RouterOS OpenVPN client to stop complaining, and it should work.