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How to create the connection between OVS bridge and the linux bridge?

asked 2013-08-20 06:09:40 -0500

rever gravatar image

updated 2013-08-23 15:38:00 -0500

smaffulli gravatar image

I have a networking problem because my VMs are unable to get an IP from the DHCP. I have been investigating and I have found that when I type:

brctl show

I see the qbr bridge with the tap and the qvb interface. However, I am missing the connection from that bridge to the OVS bridge switch (the so-called veth). In the OVS I have the br-int bridge configured.

Do I have to manually create the conection between OVS bridge and the linux bridge or should it be created automatically and I am missing something in the config files? Is there any way to check the veth configuration?


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SnowWolf gravatar imageSnowWolf ( 2013-10-14 21:17:13 -0500 )edit

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answered 2015-02-18 10:07:56 -0500

osdiaj gravatar image

A veth pair is generally used to connect a linux bridge to OVS bridge (or vice-versa). Usually in OpenStack, the veth between the qvbXXXX (belongs to qbrXXXX) and qvoXXXX (belongs to br-int) should be setup automatically. Have a look at ( .

There are ways to check this (assuming you have a single instance for simplicity) :-

(1) Note the qvbXXXX in brctl show and do ip link show qvbXXXX. Note the index(a number) before colon e.g. 3180 below

[root@compute ]# ip link show qvb016ef9bc-ba

3180: qvb016ef9bc-ba: <broadcast,multicast,promisc,up,lower_up> mtu 1500 qdisc pfifo_fast master qbr016ef9bc-ba state UP mode DEFAULT qlen 1000 link/ether f2:8f:48:f2:01:2a brd ff:ff:ff:ff:ff:ff

(2) Note the qvoXXXX in ovs-vsctl list-ifaces br-int and do ip link show qvoXXXX. Note the index before colon

(3) Now do ethtool -S qvoXXXX | grep peer_ifindex* and ethtool -S qvbXXXX | grep peer_ifindex. They should be showing each other's indices, if configured properly.

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Asked: 2013-08-20 06:09:40 -0500

Seen: 2,142 times

Last updated: Feb 18 '15