No, you're not alone, I'm facing exactly this problem, too. I used the following settings:
IP 131.173.12.227 (yes, this is a public address)
Netmask 255.255.255.0
GW 131.173.12.254
NS 131.173.245.9
When selecting the connection, knetworkmanager prints:
Activate Connection /org/freedesktop/NetworkManagerSettings/Connection/2 on Device /org/freedesktop/Hal/devices/net_00_00_f0_7a_97_d0
And syslog says:
Nov 3 14:02:40 sam NetworkManager: <WARN> connection_get_settings_cb(): connection_get_settings_cb: Invalid connection: 'NMSettingIP4Config' / 'addresses' invalid: 1
Nov 3 14:02:40 sam NetworkManager: <WARN> connection_get_settings_cb(): connection_get_settings_cb: Invalid connection: 'NMSettingIP4Config' / 'addresses' invalid: 1
Nov 3 14:02:57 sam NetworkManager: connection_updated_cb: assertion `old_connection != NULL' failed
I've replaced knetworkmanager by nm-applet which works fine with the same settings, but of course this is not a real solution but a really dirty workaround.
No, you're not alone, I'm facing exactly this problem, too. I used the following settings:
IP 131.173.12.227 (yes, this is a public address)
Netmask 255.255.255.0
GW 131.173.12.254
NS 131.173.245.9
When selecting the connection, knetworkmanager prints: p/NetworkManage rSettings/ Connection/ 2 on Device /org/freedeskto p/Hal/devices/ net_00_ 00_f0_7a_ 97_d0
Activate Connection /org/freedeskto
And syslog says: get_settings_ cb(): connection_ get_settings_ cb: Invalid connection: 'NMSettingIP4Co nfig' / 'addresses' invalid: 1 get_settings_ cb(): connection_ get_settings_ cb: Invalid connection: 'NMSettingIP4Co nfig' / 'addresses' invalid: 1 updated_ cb: assertion `old_connection != NULL' failed
Nov 3 14:02:40 sam NetworkManager: <WARN> connection_
Nov 3 14:02:40 sam NetworkManager: <WARN> connection_
Nov 3 14:02:57 sam NetworkManager: connection_
I've replaced knetworkmanager by nm-applet which works fine with the same settings, but of course this is not a real solution but a really dirty workaround.