Software-defined networks in the Havana release of Openstack – Part 2

Software Defined Networks in the Havana release of Openstack – Part 2

In the first article in this series, we looked at a simple OpenStack setup with one controller node, one compute node, and one network node. Two tenants had been created with two simple networks. In this article we will turn our attention to the network paths for each of the three VMs that were created. The diagrams in the first article are useful in understanding this discussion.

Discussion hen continues with the first half of the iptables chains that are interjected between the VM and the Open vSwitch process (OVS) on the compute node. In order to keep these articles in bite sized chunks, we will end this s ection after looking at the first two iptables chains, those starting with neutron – which manage the security group rules, the next article continue s through the iptables chains looking at those starting with nova and concludes by reviewing how two different types of packets progress through these chains.

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