openstack-kubelet-nodename.service fails when we deploy OCP 4.14 on baremetal nodes using OpenStack Ironic on RHOSP 17.1 + ML2/OVN environments.

OpenStack usually provide metadata using the following two ways

• Metadata service hosted on 169.254.169.254
• config-drive which is stored on "config-2" labeled local partition

When we create an instance on a baremetal node on a RHOSP 17.1 + ML2/OVN environment, the instance cannot access the metadata service hosted on 169.254.169.254 ( if my understanding is correct, this is expected behavior and limitation).
The instance should refers to the config-drive instead of the metadata server.

However, on OCP 4.14, openstack-kubelet-nodename.service accesses the metadata server on 169.254.169.254, and it doesn't refer to config-drive.

/etc/systemd/system/openstack-kubelet-nodename.service 

[Unit]
Description=Fetch kubelet node name from OpenStack metadata
# Wait for NetworkManager to report it's online
After=NetworkManager-wait-online.service
# Run before kubelet
Before=kubelet-dependencies.target

[Service]
ExecStart=/usr/local/bin/openstack-kubelet-nodename
Type=oneshot

[Install]
WantedBy=network-online.target

/usr/local/bin/openstack-kubelet-nodename

#!/bin/bash
set -e -o pipefail

NODECONF=/etc/systemd/system/kubelet.service.d/20-openstack-node-name.conf

if [ -e "${NODECONF}" ]; then
    echo "Not replacing existing ${NODECONF}"
    exit 0
fi

# For compatibility with the OpenStack in-tree provider
# Set node name to be instance name instead of the default FQDN hostname
#
# https://docs.openstack.org/nova/victoria/user/metadata.html#metadata-openstack-format
name=$(curl -s http://169.254.169.254/openstack/2012-08-10/meta_data.json | jq -re .name)
cat > "${NODECONF}" <<EOF
[Service]
Environment="KUBELET_NODE_NAME=${name}"
EOF 

That's why openstack-kubelet-nodename.service fails when we deploy OCP 4.14 on baremetal nodes using OpenStack Ironic on RHOSP 17.1 + ML2/OVN environments.

This issue won't occur in the latest OCP because of the following change.
By the followoing change, openstack-kubelet-nodename.service refers to config-drive when it's available.

• https://issues.redhat.com/browse/OSASINFRA-3585
• https://github.com/openshift/machine-config-operator/pull/4586/files