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I wanted to set up a bridge connection for my VMs (I am using KVM). I modified my etc/network/interfaces file and its contents are:

auto lo
iface lo inet loopback
auto br0
iface br0 inet dhcp
bridge_ports eth0
bridge_fd 9
bridge_hello 2
bridge_maxage 12
bridge_stp off

After modifying the etc/network/interfaces file I wanted to make them active so I run the following command:

sudo /etc/init.d/networking restart

but I got the following output:

Running /etc/init.d/networking restart is deprecated because it may not enable again some interfaces

so I tried restarting network by the following command:

sudo service networking stop && sudo service networking start

I get the following output:

stop: unknown instance:

If I do :

sudo service networking start 

I get :

networking stop/waiting

and my net has stopped working after that. I am using Ubuntu 12.04 and have a wired DHCP connection.

Please try to resolve this issue so that I can successfully configure bridge for my VMs and get back my net connection.

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I've found two posts that would help you. If you have not tried these then you can give them a try: How to setup bridged networking in KVM - Tutorial and KVM/Networking – Saurav Kumar Sep 14 '13 at 19:01

As you found you are getting a warning doing it the way you mentioned. If your physically at your computer do this:

sudo ifdown -a
sudo ifup -a

For SSH session one should read:

Anyhow for SSH you might do this:

sudo nohup sh -c "ifdown eth0 -a && ifup eth0 -a"

another suggestion about bridging is mentioned here:

share|improve this answer

I did sudo /etc/init.d/networking restart and my net started working.

Also, the command:

brctl show

shows my bridge is created.

My problem is solved!

share|improve this answer
you should accept your own answer – Pete Aug 8 '14 at 0:57

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