installed latest network-manager from ppa and still got same issue:
openvpn connects OK but after few seconds nm creates Auto tap0 connection under wired tab and starts querying ip via dhcp which kills ip already assigned to tap0 by openvpn server.
I was able to overcome this by adding
iface tap0 inet dhcp
line to /etc/network/interfaces file so nm does not manage tap0. (It still creates one but it does not start dhcp query on it)
installed latest network-manager from ppa and still got same issue:
openvpn connects OK but after few seconds nm creates Auto tap0 connection under wired tab and starts querying ip via dhcp which kills ip already assigned to tap0 by openvpn server.
I was able to overcome this by adding
iface tap0 inet dhcp
line to /etc/network/ interfaces file so nm does not manage tap0. (It still creates one but it does not start dhcp query on it)