Visualizing Neutron Networking with GraphViz
I've put together a few tools to help gather information about your Neutron and network configuration and visualize it in different ways. All of these tools are available as part of my neutron-diag repository on GitHub.
In this post I'm going to look at a tool that will help you visualize the connectivity of network devices on your system.read more
Quantum in Too Much Detail
I originally posted this article on the RDO website.
This document describes the architecture that results from a particular OpenStack configuration, specifically:
- Quantum networking using GRE tunnels;
- A dedicated network controller;
- A single instance running on a compute host
Much of the document will be relevant to other configurations, but details will vary based on your choice of layer 2 connectivity, number of running instances, and so forth.
The examples in this document were generated on a system with Quantum
networking but will generally match what you see under Neutron as
well, if you replace
neutron in names. The OVS flow
rules under Neutron are somewhat more complex and I will cover those
in another post.
Why does the Neutron documentation recommend three interfaces?
The documentation for configuring Neutron recommends that a network controller has three physical interfaces:
Before you start, set up a machine to be a dedicated network node. Dedicated network nodes should have the following NICs: the management NIC (called MGMT_INTERFACE), the data NIC (called DATA_INTERFACE), and the external NIC (called EXTERNAL_INTERFACE).
People occasionally ask, "why three interfaces? What if I only have two?", so I wanted to provide an extended answer that might help people understand what the interfaces are for and what trade-offs are involved in using fewer interfaces.read more
Waiting for networking using PowerShell
I've recently been exploring the world of Windows scripting, and I ran into a small problem: I was running a script at system startup, and the script was running before the network interface (which was using DHCP) was configured.
There are a number of common solutions proposed to this problem …read more
Chasing OpenStack idle connection timeouts
The original problem
In order to gather some data on the problem, I ran the following simple test: