Can't find proper metadata source IP - Interoperability problem with CentOS8/Stream, NetworkManager and Apache CloudStack

This bug was originally filed in Launchpad as [LP: #1915216](https://bugs.launchpad.net/cloud-init/+bug/1915216)

Launchpad details

affected_projects = []

assignee = None

assignee_name = None

date_closed = None

date_created = 2021-02-09T23:35:27.906402+00:00

date_fix_committed = None

date_fix_released = None

id = 1915216

importance = medium

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1915216

milestone = None

owner = jdoe666

owner_name = Peter M.

private = False

status = confirmed

submitter = jdoe666

submitter_name = Peter M.

tags = []

duplicates = []

_Launchpad user **Peter M.(jdoe666)** wrote on 2021-02-09T23:35:27.906402+00:00_

System environment: Apache CloudStack 4.11; KVM zone

In CentOS 8 either Upstream, there is NetworkManager. cloud-init currently packaged there is 20.3-9.el8.

We are talking about the code of the CloudStack datasource.

What we observe, is that on our CentOS test systems, cloud-init jumps into the default_gateway() method to return VR IP address 192.xxx.xxx.1. This is however wrong, this IP does not return metadata. To compare, an Ubuntu 20.04 deployed on same network resolves to 192.xxx.xxx.5.

This IP can be found under /run/NetworkManager:

./NetworkManager/resolv.conf:nameserver 192.xxx.xxx.5
./NetworkManager/no-stub-resolv.conf:nameserver 192.xxx.xxx.5
./NetworkManager/devices/2:next-server=192.xxx.xxx.5

While CloudStack datasource follows several approaches to find the IP, the code does not seem to implement the situation when there is NetworkManager.

What happens instead:

- first approach is to try data-server DNS entry first; this is up to our system, we will try out as well
- then, it looks for DHCP lease file location "/run/systemd/netif/leases". For some reason, this value is a hardcoded variable in net/dhcp.py: NETWORKD_LEASES_DIR = '/run/systemd/netif/leases'
- then, it finds lease file /var/lib/NetworkManager/internal-ea2b5464-7c5e-3243-aa40-7d77805f41ee-ens3.lease, but there is (as opposite to what we see in Ubuntu) just one line, "ADDRESS=192.xxx.xxx.34" - why this file does not contain the expected entry "SERVER_ADDRESS=192.xxx.xxx.5" as well, I am not sure.
- well and finally it is going to the default gateway method.

Would you say this is a bug, or maybe a missing feature to ensure interoperability with NetworkManager? (in terms that cloudinit does not look under /run/NetworkManager/)