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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">>></span> With tcpdump I can see instance making the ARP request 'who has 192.168.0.1'. However, the first answer is from bridge qvb, using the bridge mac address.<span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I believe this is due to L2 population + ARP responder mechanism where OVS itself creates an ARP reply and sends it back to avoid the ARP flooding. However, the
reply should have the gateway’s MAC as its source. What source MAC do you see in the ARP reply?<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Have you disabled reverse path filtering on your compute nodes (/etc/sysctl.conf) ?:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">net.ipv4.conf.all.rp_filter=0<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">net.ipv4.conf.default.rp_filter=0<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">-Kaustubh<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Jorge Luiz Correa [mailto:correajl@gmail.com]
<br>
<b>Sent:</b> Monday, May 16, 2016 3:35 PM<br>
<b>To:</b> openstack@lists.openstack.org<br>
<b>Subject:</b> [Openstack] Brigde on compute node confusing tenant network with system interface.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi list! I'm having problems with tenant network and one of compute nodes. I think that could be something with the compute node management ip address.<br>
<br>
Context: <br>
<br>
I'm testing the network scenario "classic with openvswitch" described here:<br>
<br>
<a href="http://docs.openstack.org/liberty/networking-guide/scenario-classic-ovs.html">http://docs.openstack.org/liberty/networking-guide/scenario-classic-ovs.html</a><br>
<br>
1 controller node, 1 network node and 2 compute nodes. <br>
<br>
Compute node 1 has 4 interfaces:<br>
<br>
p3p1 - 192.168.0.1 (management network)<br>
p3p2 - 192.168.1.1 (tunnel network)<br>
p4p2 - no address (vlan network)<br>
em4 - no address (external network)<br>
<br>
When I create a tenant network with network address <a href="http://192.168.0.0/24">
192.168.0.0/24</a>, instances launched on compute node 1 are having connectivity problem because they can't reach the network gateway 192.168.0.1.
<br>
<br>
Openvswitch agent creates a qbr bridge with a tap and a qvb interface. The instance has the address 192.168.0.5. When I try to ping 192.168.0.1 from this instance (its gateway), it doesn't work. With tcpdump I can see instance making the ARP request 'who has
192.168.0.1'. However, the first answer is from bridge qvb, using the bridge mac address. The correct would be the interface from virtual router, as I can see on compute node 2.
<br>
<br>
I think the IP address 192.168.0.1 on the management interface is making, for some reason, the bridge reply as if it was the gateway of tenant network.
<br>
<br>
This just occur with this address 192.168.0.1! If I create the tenant subnet with address
<a href="http://172.16.0.0/24">172.16.0.0/24</a> everything works great. Or, if I change the default setting for gateway address, make the gateway has another IP like 192.168.0.254, everything works fine too.
<br>
<br>
Can someone help me? Are there some configuration with sysctl to solve this? Somewhere to verify?<br>
<br>
Tks!<br>
<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal">- JLC<o:p></o:p></p>
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