Comment 1 for bug 280160

Analysis:

network-manager-openvpn calls openvpn with the "--up /usr/lib/network-manager-openvpn/nm-openvpn-service-openvpn-helper" and "--up-restart" parameters. This means that nm-openvpn-service-openvpn-helper will be called when the VPN is initiated ("init" parameter) and restarted ("restart" parameter).

However the environment passed to the script is slightly different in the init and the restart cases. In particular, the "ifconfig_local" environment variable is apparently not set on the restart call.

nm-openvpn-service-openvpn-helper fails if that env var is not set (in file src/nm-openvpn-service-openvpn-helper.c):
    val = addr_to_gvalue (getenv ("ifconfig_local"));
    if (val)
        g_hash_table_insert (config, NM_VPN_PLUGIN_IP4_CONFIG_ADDRESS, val);
    else
        helper_failed (connection, "IP4 Address");

One way to avoid this is to drop the else helper_failed (like in the ifconfig_remote case that follows)...