Continuing my Bookmarks serie, here is how to tell NetworkManager to not manage an interface, thank you very much:

~# sudo cat >> /etc/NetworkManager/NetworkManager.conf << EOF
plugins+=keyfile
[keyfile]
unmanaged-devices=interface-name:IFNAME
EOF

Where IFNAME is the interface name. For example:

unmanaged-devices=interface-name:eth0

Will prevent NetworkManager to manage eth0 …