init.d script to set up bridged virtual network

virtualnet (text/plain), 2.67 KB, created by Luca Lesinigo on 2007-08-01 12:03:01 UTC

#!/sbin/runscript
# Copyright 1999-2007 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

depend() {
	before net
}

start() {
	ebegin "Setting up virtual network"
	[ ! -x /sbin/ip    ] && (eerror "cannot run /sbin/ip"    ; return 1)
	[ ! -x /sbin/brctl ] && (eerror "cannot run /sbin/brctl" ; return 1)
	[ ! -x /bin/grep   ] && (eerror "cannot run /bin/grep"   ; return 1)
	[ ! -x /bin/sed    ] && (eerror "cannot run /bin/sed"    ; return 1)
	[ ! -x /bin/cut    ] && (eerror "cannot run /bin/cut"    ; return 1)
	eindent
	for DEV in $(/sbin/ip -o link | /bin/cut -d: -f2 | /bin/grep '^ eth[0-9]*$' | /bin/cut -c 5-); do
		# get mac address of physical interface
		MAC=$(/sbin/ip -o link show eth${DEV} | /bin/sed -e s/'.*ether '// -e s/' brd.*'//)
		einfo "eth${DEV} [${MAC}]"
		eindent
		if ( /sbin/ip -o link show eth${DEV} | /bin/grep -q UP ); then
			ewarn "interface UP, skipping"
			continue
		elif ( ! /sbin/ip -o link show veth${DEV} >/dev/null 2>&1 ); then
			ewarn "corresponding veth doesn't exist, skipping"
			continue
		elif ( ! /sbin/ip -o link show vif0.${DEV} >/dev/null 2>&1 ); then
			ewarn "corresponding vif0 doesn't exist, skipping"
			continue
		elif ( /sbin/ip -o link show bridge${DEV} >/dev/null 2>&1 ); then
			ewarn "a bridge${DEV} interface already exists, skipping"
			continue
		fi
		# rename interfaces
		/sbin/ip link set eth${DEV} name peth${DEV}
		/sbin/ip link set veth${DEV} name eth${DEV}
		# create bridge (our virtual switch)
		/sbin/brctl addbr bridge${DEV}
		/sbin/brctl stp   bridge${DEV} off
		/sbin/brctl setfd bridge${DEV} 0
		/sbin/ip link set bridge${DEV} arp off
		/sbin/ip link set bridge${DEV} multicast off
		/sbin/ip link set bridge${DEV} up
		# remove mac address from physical interface
		/sbin/ip link set peth${DEV} down
		/sbin/ip link set peth${DEV} arp off
		/sbin/ip link set peth${DEV} multicast off
		/sbin/ip link set peth${DEV} addr fe:ff:ff:ff:ff:ff
		/sbin/ip addr flush peth${DEV} 2>/dev/null
		# ...and do the same to the vif0.x
		/sbin/ip link set vif0.${DEV} down
		/sbin/ip link set vif0.${DEV} arp off
		/sbin/ip link set vif0.${DEV} multicast off
		/sbin/ip link set vif0.${DEV} addr fe:ff:ff:ff:ff:ff
		/sbin/ip addr flush vif0.${DEV} 2>/dev/null
		# set up mac address on virtual interface
		/sbin/ip link set eth${DEV} addr ${MAC} arp on
		# add vif0.x to the bridge
		/sbin/brctl addif bridge${DEV} vif0.${DEV}
		/sbin/ip link set vif0.${DEV} up
		# turn on physical interface
		/sbin/ip link set peth${DEV} up
		/sbin/brctl addif bridge${DEV} peth${DEV}
		# vethX, now named ethX, is our local port to the net,
		# the usual network scripts will take care of it
		eoutdent
	done
	eoutdent
	eend $?
}