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External network setup on CentOS

asked 2020-02-21 16:18:23 -0500

rainwadj gravatar image

updated 2020-02-24 07:36:07 -0500

I have a proof-of-concept installation of OpenStack-Ansible running on 3 physical servers, all running CentOS 7. Each server has 2 network interfaces, em1 and em2. em1 is connected to the campus network (10.x.x.x/24), and em2 is connected to a private switch. OSA is configured to use em2 for management/container (br-mgmt,, vlan (br-vlan), tunnels (br-vxlan,, and storage (br-storage,

This all works fine for private networks. I can create various private networks (192.168.x.x) and connect instances to them. I can create routers between private networks and the instances on one private network can talk to the instances on another private network.

What I can't figure out is how to configure an external network so that instances can talk to the campus network and the Internet. I've tried variations on this:

$ openstack network create --share --external --provider-physical-network vlan --provider-network-type vlan EXTERNAL

$ openstack subnet create --network EXTERNAL --allocation-pool start=,end= --dns-server 10.x.x.x --gateway --subnet-range EXTSUB1

I can set this network as the gateway of a router, and I can ping the assigned interface address, but I can't ping anything else on the 172.x.x.x network or anything with a campus IP address.

I feel like I'm missing something simple/fundamental, but I can't figure out what that is.

Any ideas?

Additional info:

In the openstack_user_config.yml file, it's actually named 'vlan':

- network:
      - neutron_linuxbridge_agent
    container_bridge: "br-vlan"
    container_type: "veth"
    container_interface: "eth11"
    type: "vlan"
    range: "101:200,301:400"
    net_name: "vlan"

From /etc/sysconfig/network-scripts/ifcfg-br-vlan:

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answered 2020-02-23 13:58:29 -0500

openstack network create --share --external --provider-physical-network vlan --provider-network-type vlan EXTERNAL

What vlan you are Using here, check if segmentation I’d is correct.

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I'm not sure what you mean, but I added more info in my original post.

rainwadj gravatar imagerainwadj ( 2020-02-24 07:40:25 -0500 )edit

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Asked: 2020-02-21 16:18:23 -0500

Seen: 191 times

Last updated: Feb 24 '20