Cloudinit resets network scripts to default configuration DHCP once Config Drive is removed after sometime

This bug was originally filed in Launchpad as [LP: #1893770](https://bugs.launchpad.net/cloud-init/+bug/1893770)

Launchpad details

affected_projects = []

assignee = None

assignee_name = None

date_closed = None

date_created = 2020-09-01T11:18:55.806587+00:00

date_fix_committed = None

date_fix_released = None

id = 1893770

importance = medium

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1893770

milestone = None

owner = vradhakrishna

owner_name = vijayendra radhakrishna

private = False

status = in_progress

submitter = vradhakrishna

submitter_name = vijayendra radhakrishna

tags = []

duplicates = []

_Launchpad user **vijayendra radhakrishna(vradhakrishna)** wrote on 2020-09-01T11:18:55.806587+00:00_

Cloudinit version: 19.1
Platform: OpenStack based.
OS: RHEL, SUSE

We use config drive(/dev/sr0) as a data source to configure network interfaces in the guest but configdrive is not always available and may be removed after couple of hours from the hypervisor.

On a first boot cloudinit uses data provided in config drive and updates system level network scripts /etc/sysconfig/ifcfg-* (Static configuration of networks) files and also configures the interface in the guest.

As long as the configdrive is available, reboots will relay on system scripts for the configuring network but once configdrive is removed, datasource becomes None meaning it neither system script nor config drive

which makes cloud init to configure default network which is DHCP