Open vSwitch components in network node

Let us begin with an overview of Open vSwitch bridges created in the network node.

The Open vSwitch agent creates the following OVS bridge interfaces as per configuration options:

• br-int: Network service components connect to this OVS Integration Bridge to offer services such as DHCP, SNAT, and routing. Compute instances connect to this bridge to obtain network services.

• br-vlan, br-tun: This communicates with compute nodes on the Tunnel Bridge. It has open flow rules to match and forward the traffic destined to the services on the network node or else drops the packets.

• br-ex: Traffic to external network flows through br-ex via the interface in the router name space, which connects to the br-ex as tap interface.

  

  Figure 1: OVS bridges on a network node

Neutron DHCP

The DHCP agent managing the qdhcp network namespaces provides DHCP services for instances.

Neutron routing

The Neutron router routes traffic between north-south and east-west network traffic...