cloud-init does not support ignoring a network interface with NetworkManager

This bug was originally filed in Launchpad as [LP: #1914784](https://bugs.launchpad.net/cloud-init/+bug/1914784)

Launchpad details

affected_projects = []

assignee = None

assignee_name = None

date_closed = None

date_created = 2021-02-05T17:46:24.098626+00:00

date_fix_committed = None

date_fix_released = None

id = 1914784

importance = undecided

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1914784

milestone = None

owner = trstringer

owner_name = Thomas Stringer

private = False

status = triaged

submitter = trstringer

submitter_name = Thomas Stringer

tags = []

duplicates = []

_Launchpad user **Thomas Stringer(trstringer)** wrote on 2021-02-05T17:46:24.098626+00:00_

NetworkManager will attempt to manage all network interfaces with no configuration. To ignore an interface, you need to specify an ifcfg file in /etc/sysconfig/network-scripts to include "NM_CONTROLLED=no".

Currently, cloud-init does not have support for the NM_CONTROLLED option or any way for a data source to explicitly generate config to tell NetworkManager to ignore a particular interface.

This functionality is currently possible with Netplan, and this report is a request for feature parity in NetworkManager config rendering.