#!/bin/sh

# This allows NFS booting to work while also being able to configure
# the network interface via DHCP when not NFS booting.  Otherwise, a
# NFS booted system will likely hang during DHCP configuration.

# Attempting to configure the network interface used for NFS will
# initially bring that network down.  Since the root filesystem is
# accessed over this network, the system hangs.

# This script is run by ifup and will attempt to detect if a NFS root
# mount uses the interface to be configured (IFACE), and if so does
# not configure it.  This should allow the same build to be disk/flash
# booted or NFS booted.

nfsip=`sed -n '/^[^ ]*:.* \/ nfs.*[ ,]addr=\([0-9.]\+\).*/s//\1/p' /proc/mounts`
if [ -n "$nfsip" ] && ip route get to "$nfsip" | grep -q "dev $IFACE"; then
	echo Skipping $IFACE, used for NFS from $nfsip
	exit 1
fi