json-tools: cli for generating and filtering json

Sun 17 November 2013 by Lars Kellogg-Stedman Tags json openstack

Interacting with JSON-based APIs from the command line can be difficult, and OpenStack is filled with REST APIs that consume or produce JSON. I've just put pair of tools for generating and filtering JSON on the command line, called collectively json-tools.

Both make use of the Python dpath module to …

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Quantum in Too Much Detail

Thu 14 November 2013 by Lars Kellogg-Stedman Tags openstack quantum networking

I originally posted this article on the RDO website.

The players

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 quantum by neutron in names. The OVS flow rules under Neutron are somewhat more complex and I will cover those in another post.

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A random collection of OpenStack Tools

Tue 12 November 2013 by Lars Kellogg-Stedman Tags openstack

I've been working with OpenStack a lot recently, and I've ended up with a small collection of utilities that make my life easier. On the odd chance that they'll make your life easier, too, I thought I'd hilight them here.

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Why does the Neutron documentation recommend three interfaces?

Mon 28 October 2013 by Lars Kellogg-Stedman Tags openstack neutron networking

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.

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Automatic configuration of Windows instances in OpenStack, part 1

Sun 04 November 2012 by Lars Kellogg-Stedman Tags openstack windows

This is the first of two articles in which I discuss my work in getting some Windows instances up and running in our OpenStack environment. This article is primarily about problems I encountered along the way, while the second article focuses on the mechanism I eventually put in place.

Motivations …

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