Not able to reproduce, looks like that directory is provided by the package.
root@testsmb1:~# dpkg -L samba | grep private /var/lib/samba/private -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to samba in Ubuntu. https://bugs.launchpad.net/bugs/1268180 Title: net join doesn't work by default since switch to 4.x To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/samba/+bug/1268180/+subscriptions -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs