Networking maintenance

Networking maintenance

Operational considerations, like compliance, can make it necessary to manage networks. For example, adding new provider networks to the OpenStack-Ansible managed cloud. The following sections are the most common administrative tasks outlined to complete those tasks.

For more generic information on troubleshooting your network, see the Network Troubleshooting chapter in the Operations Guide.

For more in-depth information on Networking, see the Networking Guide.

Add provider bridges using new network interfaces

Add each provider network to your cloud to be made known to OpenStack-Ansible and the operating system before you can execute the necessary playbooks to complete the configuration.

OpenStack-Ansible configuration

All provider networks need to be added to the OpenStack-Ansible configuration.

Edit the file /etc/openstack_deploy/openstack_user_config.yml and add a new block underneath the provider_networks section:

The container_bridge setting defines the physical network bridge used to connect the veth pair from the physical host to the container. Inside the container, the container_interface setting defines the name at which the physical network will be made available. Make sure that both settings are uniquely defined across their provider networks and that the network interface is correctly configured inside your operating system. group_binds define where this network need to attached to, to either containers or physical hosts and is ultimately dependent on the network stack in use. For example, Linuxbridge versus OVS. The configuration range defines Neutron physical segmentation IDs which are automatically used by end users when creating networks via mainly horizon and the Neutron API. Similar is true for the net_name configuration which defines the addressable name inside the Neutron configuration. This configuration also need to be unique across other provider networks.

For more information, see Configure the deployment in the OpenStack-Ansible Deployment Guide.

OpenStack-Ansible playbooks

After the initial configuration, update the container network configuration with the following playbook. Ensure you restart the container towards the end of the playbook run. We advise to either limit, or reduce, the number of forks to make sure that enough services are available. For example:

# openstack-ansible lxc-containers-create.yml --limit infra01:infra01-host_containers
# openstack-ansible lxc-containers-create.yml --limit infra02:infra02-host_containers
# openstack-ansible lxc-containers-create.yml --limit infra03:infra03-host_containers

Update the Neutron configuration. Specifically, run the neutron-config tag, in order to only alter the configration and restart the Neutron agent services:

# openstack-ansible os-neutron-install.yml --tags neutron-config

Remove provider bridges from OpenStack

Similar to adding a provider network, the removal process uses the same procedure but in a reversed order. The Neutron ports will need to be removed, prior to the removal of the OpenStack-Ansible configuration.

  1. Unassign all Neutron floating IPs:


    Export the Neutron network that is about to be removed as single UUID.

    export NETWORK_UUID=<uuid>
    for p in $( neutron port-list -c id --device_owner compute:nova --network_id=${NETWORK_UUID}| awk '/([A-Fa-f0-9]+-){3}/ {print $2}' ); do
      floatid=$( neutron floatingip-list -c id --port_id=$p | awk '/([A-Fa-z0-9]+-){3}/ { print $2 }' )
      if [ -n "$floatid" ]; then
        echo "Disassociating floating IP $floatid from port $p"
        neutron floatingip-disassociate $floatid
  2. Remove all Neutron ports from the instances:

    export NETWORK_UUID=<uuid>
    for p in $( neutron port-list -c id -c device_id --device_owner compute:nova --network_id=${NETWORK_UUID}| awk '/([A-Fa-f0-9]+-){3}/ {print $2}' ); do
      echo "Removing Neutron compute port $p"
      neutron port-delete $p
  3. Remove Neutron router ports and DHCP agents:

    export NETWORK_UUID=<uuid>
    for line in $( neutron port-list -c id -c device_id --device_owner network:router_interface --network_id=${NETWORK_UUID}| awk '/([A-Fa-f0-9]+-){3}/ {print $2 "+" $4}' ); do
      p=$( echo "$line"| cut -d'+' -f1 ); r=$( echo "$line"| cut -d'+' -f2 )
      echo "Removing Neutron router port $p from $r"
      neutron router-interface-delete $r port=$p
    for agent in $( neutron agent-list -c id --agent_type='DHCP Agent' --network_id=${NETWORK_UUID}| awk '/([A-Fa-f0-9]+-){3}/ {print $2}' ); do
      echo "Remove network $NETWORK_UUID from Neutron DHCP Agent $agent"
      neutron dhcp-agent-network-remove "${agent}" $NETWORK_UUID
  4. Remove the Neutron network:

    export NETWORK_UUID=<uuid>
    neutron net-delete $NETWORK_UUID
  5. Remove the provider network from the provider_networks configuration of the OpenStack-Ansible configuration /etc/openstack_deploy/openstack_user_config.yml and re-run the following playbooks:

    # openstack-ansible lxc-containers-create.yml --limit infra01:infra01-host_containers
    # openstack-ansible lxc-containers-create.yml --limit infra02:infra02-host_containers
    # openstack-ansible lxc-containers-create.yml --limit infra03:infra03-host_containers
    # openstack-ansible os-neutron-install.yml --tags neutron-config

Move from Open vSwitch to LinuxBridge and vice versa

Restart a Networking agent container

Under some circumstances, configuration or temporary issues, one specific or all neutron agents container need to be restarted.

This can be accomplished with multiple commands:

  1. Example of rebooting still accessible containers.

    This example will issue a reboot to the container named with neutron_agents_container_hostname_name from inside:

    # ansible -m shell neutron_agents_container_hostname_name -a 'reboot'
  2. Example of rebooting one container at a time, 60 seconds apart:

    # ansible -m shell neutron_agents_container -a 'sleep 60; reboot' --forks 1
  3. If the container does not respond, it can be restarted from the physical network host:

    # ansible -m shell network_hosts -a 'for c in $(lxc-ls -1 |grep neutron_agents_container); do lxc-stop -n $c && lxc-start -d -n $c; done' --forks 1
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