From 71c75a5ea0e62786d279ef1609f23732bde5acc3 Mon Sep 17 00:00:00 2001 From: Trent Piepho Date: Mon, 9 Nov 2015 22:16:49 +0000 Subject: [PATCH] system: Fix for NFS booting with interface config via DHCP Configuring the network interface with DHCP via /etc/network/interfaces generally does not work when NFS booting. The DHCP configuration will initially bring the interface down and system then hangs at that point as the root filesystem is no longer accessable. This adds a script to be run via a pre-up line in /etc/network/interfaces. It checks for a NFS root filesystem and if the interface to be configured is used for access to the NFS server. If this is the case, then it returns a failure code so that ifup will not configure the interface. This works for DHCP and another config methods (static, bootp, etc.). This system does detect if the interface to be configured isn't the one used for NFS and doesn't skip it when that is the case. NFS filesystems that aren't the root fs aren't considered. Fixes bug #4790. Signed-off-by: Trent Piepho Reviewed-by: Arnout Vandecappelle (Essensium/Mind) Signed-off-by: Thomas Petazzoni --- package/skeleton/nfs_check | 20 ++++++++++++++++++++ package/skeleton/skeleton.mk | 3 +++ 2 files changed, 23 insertions(+) create mode 100755 package/skeleton/nfs_check diff --git a/package/skeleton/nfs_check b/package/skeleton/nfs_check new file mode 100755 index 0000000000..dfa0cbf580 --- /dev/null +++ b/package/skeleton/nfs_check @@ -0,0 +1,20 @@ +#!/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 diff --git a/package/skeleton/skeleton.mk b/package/skeleton/skeleton.mk index d1b797ddcf..0cab8a13f1 100644 --- a/package/skeleton/skeleton.mk +++ b/package/skeleton/skeleton.mk @@ -89,8 +89,11 @@ define SET_NETWORK_DHCP echo ; \ echo "auto $(NETWORK_DHCP_IFACE)"; \ echo "iface $(NETWORK_DHCP_IFACE) inet dhcp"; \ + echo " pre-up /etc/network/nfs_check"; \ echo " wait-delay 15"; \ ) >> $(TARGET_DIR)/etc/network/interfaces + $(INSTALL) -m 0755 -D $(SKELETON_PKGDIR)/nfs_check \ + $(TARGET_DIR)/etc/network/nfs_check endef endif -- 2.30.2