From mboxrd@z Thu Jan  1 00:00:00 1970
From: c.monty@web.de
Subject: Setting up network for KVM guests
Date: Thu, 26 May 2011 23:40:26 +0200 (CEST)
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Hello!
I have installed KVM/QEMU on my LMDE (Linux Mint Debian Edition) system=
=2E

On this webpage I found some instructions howto setup the network:
http://www.linux-kvm.org/page/Networking

My first question is:
=46or a public bridge, should I configure /etc/network/interfaces in or=
der to create the bridge static.
Or should I use a script to create a bridge dynamically when the virtua=
l machine starts.

Second question:
I made some tests with this script that is shown in section
public bridge -> Solution 2: manual:

#!/bin/sh
set -x

switch=3Dbr0

if [ -n "$1" ];then
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /usr/bin/sudo /usr/sbin/tunc=
tl -u `whoami` -t $1
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /usr/bin/sudo /sbin/ip link =
set $1 up
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 sleep 0.5s
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /usr/bin/sudo /usr/sbin/brct=
l addif $switch $1
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 exit 0
else
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 echo "Error: no interface sp=
ecified"
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 exit 1
fi

When I debug this script I can see that it always ends up in "Error: no=
 interface specified":
bash -x /usr/local/bin/networkbridge_setup.sh
+ set -x
+ switch=3Dbr0
+ '[' -n '' ']'
+ echo 'Error: no interface specified'
Error: no interface specified
+ exit 1


Why is that?

THX