TL;DR A path attribute is an additional piece of information associated with a prefix, included within the UPDATE packet during route exchange. Path attribute types include: Well-known - Must be recognized by all BGP implementation Mandatory ALWAYS be included within BGP UPDATE. Discretionary MUST be recognized by ALL implementations.

Introduction Within this article, we will look at the history of spine and leaf. We will first look at the problems seen with traditional networks, the background to the spine and leaf architectures aka Clos, and then finally look at how this fits into the spine and leaf architectures of

Introduction Within this article, we will detail the steps required to build a simple networking topology in Neutron using the OpenStack CLI. Topology Our topology (Figure 1) will consist of an L3 router, an external network, a tenant network and a range of floating IPs. Our external network will be

Introduction PIM (Protocol Independent Multicast) is a multicast routing protocol, that is used to send traffic from a single source to multiple destinations across a network. PIM is a collection of three protocols - PIM Sparse Mode, PIM Dense Mode and PIM Bi-directional .  PIM is termed protocol-independent because PIM does

Introduction Today, we will be walking you through the steps required to build an OpenStack Lab using Kolla-Ansible, based on the queens release. So what is Kolla-Ansible? In short, Kolla-Ansible is a highly customizable OpenStack project that is used to deploy OpenStack services and infrastructure components in Docker containers. Once

TL;DR BFD (Bi-Directional Forwarding Detection) is a highly efficient keepalive mechanism for routing protocols, that can detect link failures in milliseconds. Background As stated at http://brbccie.blogspot.com/, All routing protocols have some way of detecting failure, usually timer-related. Tuning the timers can theoretically get you sub-second failure

DPDK DPDK (Data Plane Development Kit) is a framework (under the Linux Foundation) comprised of various userspace libraries and drivers for fast packet processing[1]. Originally developed by Intel to run on x86 based CPUs, DPDK now supports other CPU types, such as IBM POWER and ARM. Though DPDK uses

SR-IOV (Single Root I/O Virtualization) is an extension to the PCI Express (PCIe) specification. Virtual Functions (VF) are created that act like a separate physical NIC for each VM; the VF in the NIC is then given a descriptor that tells it where the user space memory, owned by

Introduction Within this article we will look at some of the issues around the native (i.e no SR-IOV, DPDK etc) Linux datapath when moving a packet through a system, from NIC to a virtual instance. We will do so by tracing the path of a packet through the system.