Read lease files from dhclient and NetworkManager on Azure and CloudStack about afterburn HOT 6 CLOSED

The CloudStack provider also reads networkd lease files via a call to dns_lease_key_lookup().

from afterburn.

We should be now in a better position to tackle this, as at least we have a single network management stack in initramfs in both RHCOS and FCOS (NM with the internal DHCP client).

from afterburn.

For reference, NM lease files do not seem to contain the DHCP option:

cat /var/lib/NetworkManager/internal-054597c7-5830-47a8-a54c-77e054ee00aa-eth0.lease 

# This is private data. Do not parse.
ADDRESS=10.1.42.5

from afterburn.

To make this ticket easier to find out, this bug currently means that on Azure we have to wait for a timeout:

[  131.232431] afterburn[1103]: WARN Failed to get fabric address from DHCP: maximum number of retries (60) reached
[  131.244800] afterburn[1103]: INFO using fallback address

It it gets too annoying to have this timeout, we could try to add some smarter heuristic in Afterburn in order to directly reach the Azure hardcoded IP.

from afterburn.

This is causing a 30 second boot delay in Azure on Fedora CoreOS (#652).

from afterburn.

The boot delay is caused by (at least) afterburn-hostname.service. These days we have a NetworkManager daemon and D-Bus in the initrd, so a D-Bus query should be sufficient. Here's a sample query on a RHEL 8 instance (not tested in the initrd), based on this:

#!/usr/bin/python3
import dbus
bus = dbus.SystemBus()
nm = bus.get_object("org.freedesktop.NetworkManager", "/org/freedesktop/NetworkManager")
conn = bus.get_object("org.freedesktop.NetworkManager", nm.Get("org.freedesktop.NetworkManager", "PrimaryConnection", dbus_interface="org.freedesktop.DBus.Properties"))
dhcp = bus.get_object("org.freedesktop.NetworkManager", conn.Get("org.freedesktop.NetworkManager.Connection.Active", "Dhcp4Config", dbus_interface="org.freedesktop.DBus.Properties"))
options = dhcp.Get("org.freedesktop.NetworkManager.DHCP4Config", "Options", dbus_interface="org.freedesktop.DBus.Properties")
print(str(options["private_245"]))

Output:

a8:3f:81:10

from afterburn.