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After adding ovs br-ex on physical public network, server connection lost

asked 2016-01-16 03:35:59 -0500

anonymous user


i am facing the bridge mapping problem, after adding the ovs external interface br-ext to the ext1 (physical public interface), connection lost to the server. I have applied manual configuration whatever mention in other blogs, but still issue is there.

Thank you very much for your reply.

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answered 2016-01-18 05:16:27 -0500

Wohard gravatar image

have a look on this link . (
you can create the interface fie if not already done.

IPADDR= # Old eth0 IP since we want the network restart to not 
                       # kill the connection, otherwise pic your something outside your dhcp range
NETMASK=  # your netmask
GATEWAY=  # your gateway
DNS1=     # your nameserver

And change the config file of your physical interface

HWADDR=52:54:00:92:05:AE # your hwaddr (find via ip link show eth0)
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answered 2017-07-21 06:33:54 -0500

Ionel gravatar image

I am in the same situation. I have installed openstack using devstack. Now I am at the point of linking br-ex interface to an external interface. I have used the above commands (ovs-vsctl , etc) and now I cannot access anymore my external interface only the br-ex interface IP. External interface is setup to use DHCP, is getting the IP but is not accessible from outside. When I am powering on instances they are hanging on powering on state. At the end, I have managed to regain access to external interface using command ovs-vsctl del-port br-ex ens160 Any suggestion to solve this situation ?

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i have same problem as my instances can't reach external network did you manage to solve it ?!

ahabib gravatar imageahabib ( 2020-04-21 06:02:56 -0500 )edit

answered 2016-01-18 05:07:43 -0500

smcas gravatar image

Assuming eth0 or ext1 interface is having internet access and br-ex bridge is set up,

ovs-vsctl add-port br-ex eth1

this command will disconnect the acess of node, Login to console and set

ifcfg eth1 0

Also ensure that br-ex is having the public ip address or the inter access network, if not , see it via CLI

ifconfig br-ex <ip-address> netmask 255.x.x.x up

This would bring back the connectivity.

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Asked: 2016-01-16 03:35:59 -0500

Seen: 6,305 times

Last updated: Jan 18 '16