title: linux eth0 is not working with bridge
body: <p>Friends, I am trying to bridge my qemu guest to the real network using linux bridge utility. <br/>
  For this, I am using very simple method : <br/></p>
  
  <ol>
  <li>Create a bridge on host using (sudo brctl addbr br0)</li>
  <li>Add eth0 to this bridge (sudo brctl addif br0 eth0)</li>
  <li>Changed /etc/qemu-ifup script (brctl addif br0 $1)</li>
  <li>Changed /etc/qemu-ifdown script (brctl delif br0 $1)</li>
  </ol>
  
  <p>With above 4 steps, I was get the network of my guest working properly.
  But now the problem is that my host network is not working after i attach my eth0 to bridge br0. </p>
  
  <p>I confirmed that after step1 and step2 my host network stops working. But the guest network continue to work and this is what baffles me. </p>
  
  <p>Can somebody please point out what is the problem with this two lines ?</p>
  
  <ol>
  <li>Create a bridge on host using (sudo brctl addbr br0)</li>
  <li>Add eth0 to this bridge (sudo brctl addif br0 eth0)</li>
  </ol>
  
  <p>PS : I have tried almost all methods given on the Internet and have not succeeded in any method. Besides my question is related to linux networking and not qemu in particular</p>