The post Worth Reading: Building a Network appeared first on 'net work.
When you first start using Ansible, you go from writing bash scripts that you upload and run on machines to running desired end state playbooks. You go from a write-once read-never set of scripts to an easily readable and updatable yaml. Life is good.
Fast forward to when you become an Ansible power user. You’re now:
Writing playbooks that run on multiple distros
Breaking down your complex Ansible project into multiple bite-sized roles
Using variables like a boss: host vars, group vars, include variable files
Tagging every possible task and role so you can jump to any execution point and control the execution flow
Sharing your playbooks with colleagues and they’ve started contributing back
As you gain familiarity with Ansible, you inevitably end up doing more and more stuff-- which in turn makes the playbooks and roles that you’re creating and maintaining longer and a bit more complex. The side effect is that you may feel that development begins to move a bit slower as you manually take the time to verify variable permutations. When you find yourself in this situation, it’s time to start testing. Here’s how to get started by using Docker and Ansible to automatically test Continue reading
Join the Datanauts for a ride to the land of GIFEE, or Google Infrastructure for Everyone Else. GIFEE is a combination of tools and processes to launch code and applications quickly and at scale. But is it relevant to you? Probably it is!
The post Datanauts 028: Google Infrastructure For Everyone Else (GIFEE) appeared first on Packet Pushers.
Join the Datanauts for a ride to the land of GIFEE, or Google Infrastructure for Everyone Else. GIFEE is a combination of tools and processes to launch code and applications quickly and at scale. But is it relevant to you? Probably it is!
The post Datanauts 028: Google Infrastructure For Everyone Else (GIFEE) appeared first on Packet Pushers.
Amazon is still a speck on the horizon, though.
Congratulations! We have managed to slay the beast that is wireless. We’ve driven a stake through it’s heart and prevented it from destroying civilization. We’ve taken a nascent technology with potential and turned it into the same faceless corporate technology as the Ethernet that it replaced. Alarmist? Not hardly. Let’s take a look at how 802.11 managed to come to an inglorious end.
Wireless used to be the wild frontier of networking. Sure, those access points bridged to the traditional network and produced packets and frames like all the other equipment. But wireless was unregulated. It didn’t conform to the plans of the networking team. People could go buy a wireless access point and put it under their desk to make that shiny new laptop with 802.11b work without needing to be plugged in.
Wireless used to be about getting connectivity. It used to be about squirreling away secret gear in the hopes of getting a leg up on the poor schmuck in the next cube that had to stay chained to his six feet of network connectivity under the desk. That was before the professionals came in. They changed wireless. They put a Continue reading
A bridge is a Layer 2 device that connects two Layer 2 (i.e. Ethernet) segments together. Frames between the two segments are forwarded based on the Layer 2 addresses (i.e. MAC addresses). Although the two words are still often used in different contexts, a bridge is effectively a switch and all the confusion started 20+ years ago for marketing purposes.
Switching was just a fancy name for bridging, and that was a 1980s technology – or so the thinking went.
A bridge makes forwarding decisions based on the MAC address table. Bridge learns MAC addresses by looking into the Frames headers of communicating hosts.
A bridge can be a physical device or implemented entirely in software. Linux kernel is able to perform bridging since 1999. By creating a bridge, you can connect multiple physical or virtual interfaces into a single Layer 2 segment. A bridge that connects two physical interfaces on a Linux host effectively turns this host into a physical switch.
Switches have meanwhile became specialized physical devices and software bridging had almost lost its place. However, with the advent of virtualization, virtual machines running on physical hosts required Layer 2 connection to the physical network Continue reading
In this episode of Network Matters with Ethan Banks, learn about the basics of OpenStack and why the open-source cloud platform has become so popular. Ethan explains exactly what OpenStack is, then dispels some of the myths around IT's expectations for OpenStack adoption.
Ethan is the co-host of the Future of Networking Summit at Interop Las Vegas. Learn more about the conference program or register for Interop, May 2-6 in Las Vegas.
These companies are forging new frontiers in software-defined networking.
If you're looking for a practical, hands-on, real world approach to learning and implementing SDN and OpenFlow, look no further. The video course Practical SDN and OpenFlow Fundamentals from GNS3 Academy offers a unique way to learn about and experiment with SDN with no risk -- using your own laptop along with free or demo software.
GNS3 Academy courses are low-cost, self-paced, work on any device, and access never expires. Plus, courses are updated monthly with new material to keep your skills current.
In this course, instructor and CCIE emeritus David Bombal demonstrates SDN and OpenFlow in detail, covering everything from the basic definition of SDN to capturing messages with Wireshark and even building your own SDN switch with Raspberry Pi.
Register for this course and you can delve into:
The first 10 Network Computing members to register receive the course FREE, so register now and enter the code NETWORKCOMPUTING.
One of my readers sent me this question:
Considering I know nothing about anything SDN-related (and considering it seems "SDN" means something different depending to whom you are asking), where should someone with no knowledge of SDN start?
The obvious answer: sdn.ipSpace.net. On a more serious note:
Read more ...The final post in a series demonstrates how to use the network-ci tools to safely replace a core routing protocol inside a small Active/Standby Data Centre.
Continue reading