* This article was written on June 8, 2021. 1. Environment OS, Opensource for YANG and NETCONF Ubuntu 18.04 LTS on VirtualBoxUbuntu version higher than 18.04 may not work libyang (https://github.com/CESNET/libyang) libnetconf2 (https://github.com/CESNET/libnetconf2) sysrepo (https://github.com/sysrepo/sysrepo) netopeer2 (https://github.com/CESNET/netopeer2) 2. Install the necessary tools, librar..