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Introduction Within this tutorial we will use NETCONF and YANG to configure an interface upon a Cisco CSR router using a combination of Python and the BASH CLI. Furthermore we will use 2 main tools – Pyang and Pyangbind. Before we start lets have a quick overview on what these tools do, Pyang is a YANG … Read more
Introduction Within the Linux kernel, knowing how memory is separated is extremely important. As knowing what programs reside where, and the requirement on the system to move memory from one place to another, can provide a huge insight into the performance, or lack of, within a system. And when it comes to the world of … Read more
Background Introduced within the Junos OS Release – 15.1X49-D100 – the vSRX now comes with cloud-init. As per Junipers configuration guide, … the cloud-init package (version 0.7x) comes pre-installed in the vSRX image to help simplify configuring new vSRX instances operating in an OpenStack environment according to a specified user-data file. Cloud-init is performed during … Read more
Introduction After troubleshooting a recent issue with accessing meta services from a guest instance, and jumping through the various steps within the path, I soon realised – this would make for a great article. Issue So first of all let’s look at the issue. The issue was pretty basic. Quite simply I was unable … Read more
Introduction NFV is a term that has been around for a few years now. As vendors and the open source communities look to drive the adoption of NFV, a wave of new acronyms and buzzwords are spreading through the industry. Within this article we will look into the various NFV components (such as standards, platforms, … Read more
An OpenStack Cloud can be divided into three main hierarchical zones – Regions, Availability Zones and Host Aggregates. Regions A Region is full OpenStack deployment, including its own API endpoints, networks and compute resources[1], excluding the Keystone and Horizon. Each Region shares a single set of Keystone and Horizon services. Host Aggregates Host Aggregates are logical … Read more
Interface to Network Security Functions (I2NSF) is a working group within the IETF formed to define a set of interfaces and data models for monitoring and managing network security functions hosted across multiple sites. I2NSF states, Network security functions (NSFs) are provided and consumed in increasingly diverse environments. Users of NSFs could consume network security … Read more
Definition MacVTap is a Linux device driver, based upon the combination of – Macvlan and TAP (descriptions below), that allows for the creation of virtual (tap-like) interfaces. Each virtual network interface is assigned its own MAC and IP address, then attached to the physical interface (also know as the lower interface), Macvlan – Linux kernel … Read more
Abstract The scope of this article is to describe, at a high level, the journey a frame takes through a Linux based system. NOTE This article does not cover Linux kernel performance issues and caveats, for more information around this please see pushing the limits of kernel networking. Ingress Lets first look at the path … Read more