[Bug] - cloud-init incorrectly adding multiple routes to systemd

[aadhik]

AL2023 has cloud-init version 22.2.2 which is incorrectly writing the Routes into systemd-network, if we open /etc/systemd/network/10-cloud-init-eth0.network

We see the following:
[Route]
Destination=168.94.58.128/26
Destination=172.29.3.128/26
Gateway=172.29.18.1

This section is incorrectly configured as it should be:

[Route]
Destination=168.94.58.128/26
Gateway=172.29.18.1

[Route]
Destination=172.29.3.128/26
Gateway=172.29.18.1
Instance ID(s):

Resolution is to upgrade to cloud-init version 23.1
canonical/cloud-init#1868

[ozbenh]

Updating cloud-init comes with a high risk... it doesn't have a great track record of backwards compatibility. We can look into backporting the specific fixes however

[ozbenh]

BTW. Is this using an on-prem image ? We don't enable cloud-init based network config by default on AMIs