ignition/02_ignition_firstboot

#!/bin/sh
exec tail -n +3 $0
# On read-only systems /boot/writable provides a writeable
# subvolume which also stores the Ignition flag file.
set flagpath="/boot/writable"

# Determine if this is a first boot and set the variable
# to be used later on the kernel command line.
set ignition_firstboot=""
if ! [ -f "${flagpath}/firstboot_happened" ]; then
    # This defaults to DHCP in dracut
    set ignition_network_kcmdline=''

    # source in the `ignition.firstboot` file which could override the
    # above $ignition_network_kcmdline with static networking config.
    # This override feature is primarily used by coreos-installer to
    # persist static networking config provided during install to the    
    # first boot of the machine.
    if [ -e "${flagpath}/ignition.firstboot" ]; then
        source "${flagpath}/ignition.firstboot"
    fi
    
    set ignition_firstboot="ignition.firstboot $ignition_network_kcmdline"
fi