I had setup the l2tp VPN information(IP, username, passwd,pre-shared key and so on), but when i clicked the connect-button, the prompt said that org.freedesktop.network-manager-l2tp was not installed. After i had cloned the Source code from the github repository and execute the "./autogen.sh" to prepare compiling the network-manager-l2tp SOURCE , it said that "no package libnma found". What would i do to solve this problem or some solutions to connect the l2tp VPN service? Sorry for my poor English. Thanks.