Make sure there's always the device and connection as well as the reason when a slave activation fails. The slave connection could in fact be chosen automatically on "nmcli d connect" and the user might not be aware activation of which connection was attempted:
$ nmcli d connect enp0s25 Error: Device activation failed: Master connection not found or invalid
6b62536 manager: make some error reporting a bit more specific
src/nm-manager.c | 43 ++++++++++++++++++++++---------------------
1 file changed, 22 insertions(+), 21 deletions(-)
Upstream: cgit.freedesktop.org