Learn Python

Around six years ago, I decided to start a website called packetlife.net. Maybe you've heard of it. Most people turn to a purpose-built content management system like Wordpress or Drupal for such an endeavor, but I needed greater flexibility to achieve some of the projects I had in mind. This meant I needed to learn a programming language and write a good amount of the site's logic myself.

I already had some experience dabbling in PHP, but wasn't thrilled with it. I figured if I was going to learn a new language, it should be useful as a general purpose language and not just for building a web site. After a bit of research and deliberation, I chose Python (and the Django web framework).

The purpose of this post is to convince networkers with little to no experience writing code to learn Python. In the past I've encouraged fellow networkers to pick up any programming language, as it's more important to think like a programmer than it is to gain proficiency in a particular language. However, I've realized that many people get stuck on which language they want to learn, lose motivation, and end up not growing proficient Continue reading

OpenDaylight at Networking Field Day 7

Networking Field Day 7 was the third Tech Field Day event I attended as a delegate, and as expected, it was a blast. Its always good to be reunited with old friends, especially in this kind of environment, where constant technical discussions are…….well, they’re just going to happen. There were certainly some common undertones in every single presentation. One big example is OpenDaylight - nearly every vendor had at least something to say about it.

OpenDaylight at Networking Field Day 7

Networking Field Day 7 was the third Tech Field Day event I attended as a delegate, and as expected, it was a blast. Its always good to be reunited with old friends, especially in this kind of environment, where constant technical discussions are…….well, they’re just going to happen. There were certainly some common undertones in every single presentation. One big example is OpenDaylight - nearly every vendor had at least something to say about it.

Integrated hybrid OpenFlow control of HP switches

Performance optimizing hybrid OpenFlow controller describes InMon's sFlow-RT controller. The controller makes use of the sFlow and OpenFlow standards and is optimized for real-time traffic engineering applications that managing large traffic flows, including: DDoS mitigation, ECMP load balancing, LAG load balancing, large flow marking etc.

The previous article provided an example of large flow marking using an Alcatel-Lucent OmniSwitch 6900 switch. This article discusses how to replicate the example using HP Networking switches.

At present, the following HP switch models are listed as having OpenFlow support:
  • FlexFabric 12900 Switch Series
  • 12500 Switch Series
  • FlexFabric 11900 Switch Series
  • 8200 zl Switch Series
  • HP FlexFabric 5930 Switch Series
  • 5920 Switch Series
  • 5900 Switch Series
  • 5400 zl Switch Series
  • 3800 Switch Series
  • HP 3500 and 3500 yl Switch Series
  • 2920 Switch Series 
Note: All of the above HP switches (and many others) support the sFlow standard - see sFlow Products: Network Equipment @ sFlow.org.

HP's OpenFlow implementation supports integrated hybrid mode - provided the OpenFlow controller pushes a default low priority OpenFlow rule that matches all packets and applies the NORMAL action (i.e. instructs the switch to apply default switching / routing forwarding to the packets).

In Continue reading

Network Configuration Templates Using Jinja2

We’ve all been there at some point in our careers - especially those that work for VARs. You’re presented with a bunch of new gear that needs to be configured and deployed, and you’re tasked with making the magic happen. It was great to wake up yesterday to read Jason Edelman’s post on Ansible for networking - taking an approach to network automation that’s built upon existing, proven tools just makes sense, especially for the use case of initial configuration, but hopefully beyond.

Network Configuration Templates Using Jinja2

We’ve all been there at some point in our careers - especially those that work for VARs. You’re presented with a bunch of new gear that needs to be configured and deployed, and you’re tasked with making the magic happen. It was great to wake up yesterday to read Jason Edelman’s post on Ansible for networking - taking an approach to network automation that’s built upon existing, proven tools just makes sense, especially for the use case of initial configuration, but hopefully beyond.

Dell Aims for the Clouds with Z9500 Spine

While at Networking Field Day 7, we got a small preview of a new switch Dell Networking has just announced, the Z9500. At some point I’ll have another post coming discussing more of Dell’s presentation at NFD7, but I wanted to briefly talk about this new product and what it brings to the table for Dell.

To be frank, Dell’s acquisition of Force10 Networks originally felt to me like a “me too” play so that Dell could compete with Cisco UCS and HP in the “full data center stack” play combining compute, storage, and networking in a single SKU or a playbook of blessed configurations. I wasn’t really expecting Dell to innovate all that much in this space. But based on the information I have at this point, I think that position is unfounded.
Here’s a picture of the new beast from a demo rack Dell showed us at NFD:
Dell Z9500

Dell Z9500

To summarize the hardware: it’s a hell of a lot of density. The Z9500 platform presents 132 line-rate 40G ports in a 3RU chassis. So, if one were inclined, one could potentially cram 14 such chassis into a standard 42RU cabinet to concentrate 1,848 40G ports into Continue reading

Ordered FIB

In a past post, we’ve discussed microloops in link state protocols. If we examine a small ring topology (if you come to my Interop talk, you’ll discover that ring topologies are the heart of network convergence), we can see where and how a microloop forms. If the link between A and B fails, A and […]

Author information

Russ White

Russ White
Principle Engineer at Ericsson

Russ White is a Network Architect who's scribbled a basket of books, penned a plethora of patents, written a raft of RFCs, taught a trencher of classes, and done a lot of other stuff you either already know about, or don't really care about. You want numbers and letters? Okay: CCIE 2635, CCDE 2007:001, CCAr, BSIT, MSIT (Network Design & Architecture, Capella University), MACM (Biblical Literature, Shepherds Theological Seminary). Russ is a Principal Engineer in the IPOS Team at Ericsson, where he works on lots of different stuff, serves on the Routing Area Directorate at the IETF, and is a cochair of the Internet Society Advisory Council. Russ will be speaking in November at the Ericsson Technology Day. he recently published The Art of Network Architecture, is currently working on a new book in the area Continue reading

Putting the Application in SDN

Putting the Application in SDN

by Steve Harriman, VP of Marketing  - March 25, 2014

We would like to highlight a couple of recent articles about SDN that reflect Packet Design’s perspective on the technology. Arthur Cole wrote in Enterprise Networking Planet about “SDN in the Enterprise: It’s the Applications, Stupid.” He rightly asserts that the value of SDN isn’t in the architecture itself, but in the applications that the environment supports. It is understandable that during the genesis of a technology, the majority of effort is spent in making it work, but we should not lose site of the fact that optimal application performance is the key to deploying SDN more broadly. And we as an industry are not nearly ready to effectively manage applications across software-defined networks.

IsaacMao via Compfight cc 

In fact, Cole cites an article written by our own CTO Cengiz Alaettinoglu in Data Center Knowledge about how traditional, manual management methods are inadequate in a programmable, automated network environment. We need to automate network management best practices and processes to give human operators the visibility and control needed to adequately manage SDN applications in the data center and across the WAN. Continue reading

Performance optimizing hybrid OpenFlow controller

The latest release of InMon's sFlow-RT controller adds integrated hybrid OpenFlow support - optimized for real-time traffic engineering applications that manage large traffic flows, including: DDoS mitigation, ECMP load balancing, LAG load balancing, large flow marking etc.

This article discusses the evolving architecture of software defined networking (SDN) and the role of analytics and traffic engineering. InMon's sFlow-RT controller is used to provide practical examples of the architecture.
Figure 1: Fabric: A Retrospective on Evolving SDN
The article, Fabric: A Retrospective on Evolving SDN by Martin Casado, Teemu Koponen, Scott Shenker, and Amin Tootoonchian, makes the case for a two tier software defined networking (SDN) architecture; comprising a smart edge and an efficient core. The article, Pragmatic software defined networking on this blog, examines how the edge is moving into virtual switches, with tunneling (VxLAN, NVGRE, GRE, STT) used to virtualize the network and decouple the edge from the core. As complex policy decisions move to the network edge, the core fabric is left with the task of efficiently managing physical resources in order to deliver low latency, high bandwidth connectivity between edge switches.

First generation SDN controllers were designed before the edge / core split became Continue reading

Restoring Trust in the Internet – Part 2

In my last post I talked about the broken trust in the Internet. Now let’s talk about steps we need to take to restore that trust. First, we need to realize that trust is regained by proving we are trustworthy. There is nothing we can do, or say, that will instantly restore trust; it is […]

Author information

Jonathan Strine

Jonathan Strine

Jonathan Strine is a Network Engineer who's been in the IT industry since the turn of the century and holds a CCNP, CCDP, and is preparing for the CCIE lab. His experience covers a variety of industries. He currently works for Cisco where he gets to play with new equipment in the lab all day. Well, some days at least. His and his wife's long term goal is to downsize to a 500 sq-ft house and live simply. To contact him directly and securely, please see his current PGP Keys.

The opinions and views expressed are solely his and not necessarily those of his current or previous employers.

LinkedIn

The post Restoring Trust in the Internet – Part 2 appeared first on Packet Pushers Podcast and was written by Jonathan Strine.

Taking the Old Approach to Cisco Live 2014

I was just reading through Bob’s blog post from today and wanted to give a rebuttal of sorts.  In his post, Bob tells us that’s he’s going to be at Cisco Live US in San Francisco this year but he won’t be coming on the Full Conference pass like he usually does.  He’s going with the Social Event pass this year, which is actually a great, great way to attend.  I know several people who are thinking about scaling back to the Social Event pass as well, and there’s nothing wrong with doing it like that.  There are some things that it doesn’t get you, though.

The Social Event pass means no breakout sessions.  These are the bread-and-butter of the conference and the real technical reason that I try to go each year (listen to me talk like I’m a 20-year NetVet…LOL).  Yes, most of the sessions are available on Cisco Live 365 afterwards, but that leaves two problems for me.  First of all, I will never actually make the time to go back and sit through these sessions after the event.  It’s just something that won’t happen with life and work and everything going on.  Secondly, I cannot sit Continue reading

The Foundation of Network Programmability

Ever since I entered this field, I’ve been interested in this concept of “network programmability”. Forgetting for a second what we’ve been talking about in the past few years since the advent of the “SDN tsunami”, even the ability to automate simple infrastructure tasks at a small scale has grabbed my attention. It’s important to note something here; the CLI is a wonderful tool. So many vendors take the wrong approach and say the CLI is going away in lieu of pretty GUIs and APIs, as if someone can’t write a really good CLI to consume a really good API.

The Foundation of Network Programmability

Ever since I entered this field, I’ve been interested in this concept of “network programmability”. Forgetting for a second what we’ve been talking about in the past few years since the advent of the “SDN tsunami”, even the ability to automate simple infrastructure tasks at a small scale has grabbed my attention. It’s important to note something here; the CLI is a wonderful tool. So many vendors take the wrong approach and say the CLI is going away in lieu of pretty GUIs and APIs, as if someone can’t write a really good CLI to consume a really good API.

Ansible for Networking

[This article is the outcome of some great conversations and exchanges I’ve had recently with Jeremy Schulman (@nwkautomaniac) around automation and Devops in the world of networking.  Thank you to Jeremy for those late tweaks before getting this posted!  Thanks to Kirk Byers (@kirkbyers) as well - he was also gracious enough to respond to clarify a few things and assisted with this post indirectly.]

There have been numerous articles written that describe the what and the why of Devops.  Reading through a few of these, you find references to CAMS --- you’ll read how “Devops is about CAMS.”  CAMS stands for Culture, Automation, Measurement, and Sharing.  Imagine working in an environment where automation is embraced?  We know most networks are not leveraging nearly any type of automation.  While we usually talk about engineers (of all types) not embracing automation, is the harsh reality most organizations are from having the right culture to embrace automation? 
What if there was a way to start testing network automation without taking a risk in a production environment?  And to top it off, the network automation was being done using some of the same tools that Continue reading

Taking a New Approach to Cisco Live 2014

It’s getting to be that time of year again when geeks across North America (and beyond) start getting excited for Cisco Live! The buzz is starting a bit early this year, but that’s because Cisco Live is about a month earlier this year (May 18-22) than it has been in recent years.

Introduction

Many of the exciting details of the event have surfaced at this point, including the announcement of Salman Khan, founder of Khan Academy as the closing guest keynote speaker, and that the Customer Appreciation Event will feature Lenny Kravitz and the Imagine Dragons as musical acts. We’ve even seen this year’s backpack design, courtesy of a couple Tweets from Cisco’s Kathleeen Mudge:

Last year, I put together a post of Cisco Live tips, most of which are just as applicable this year as last. My personal approach, however, will be a bit different this year.

Plans Continue reading

Show 184 – The Future of Networking Part 2 as Inspired by #NFD7

At Networking Field Day 7, the delegates were treated to vendor demonstrations that challenged our thinking about the future of networking. Perhaps the industry is not agreed on just how we’ll implement and operate our networks in the coming years, but one thing is for certain. The landscape will be different. In this and the previously […]

Author information

Ethan Banks

Co-host at Packet Pushers

Ethan Banks, CCIE #20655, has been managing networks for higher ed, government, financials and high tech since 1995. Ethan co-hosts the Packet Pushers Podcast, which has seen over 2M downloads and reaches over 10K listeners. With whatever time is left, Ethan writes for fun & profit, studies for certifications, and enjoys science fiction. @ecbanks
TwitterGoogle+LinkedIn

The post Show 184 – The Future of Networking Part 2 as Inspired by #NFD7 appeared first on Packet Pushers Podcast and was written by Ethan Banks.

Review: Hadoop Operations

Hadoop Operations Eric Sammer Hadoop is one of those applications all data centers seem to need to support – and there is a lot of information out there about how Hadoop works, how to use it, and how to build Hadoop systems. From these, it’s pretty easy to glean a general set of requirements for […]

Author information

Russ White

Russ White
Principle Engineer at Ericsson

Russ White is a Network Architect who's scribbled a basket of books, penned a plethora of patents, written a raft of RFCs, taught a trencher of classes, and done a lot of other stuff you either already know about, or don't really care about. You want numbers and letters? Okay: CCIE 2635, CCDE 2007:001, CCAr, BSIT, MSIT (Network Design & Architecture, Capella University), MACM (Biblical Literature, Shepherds Theological Seminary). Russ is a Principal Engineer in the IPOS Team at Ericsson, where he works on lots of different stuff, serves on the Routing Area Directorate at the IETF, and is a cochair of the Internet Society Advisory Council. Russ will be speaking in November at the Ericsson Technology Day. he recently published The Art of Network Architecture, is currently working on a new book in the area Continue reading

HP Comware-based Switches – Link Aggregation

The 3Com/HPN/H3C based Switches offers the utilization of interfaces such as Ethernet, Fast Ethernet, GigabitEthernet or TenGigabitEthernet. The Link Aggregation feature allows the gathering of many ports in order to increase the link’s velocity concerning the full duplex communication between the two devices.

In Link-Aggregation mode the ports are utilized in parallel, supporting the bandwith’s growth and expansion, without the need of buying an additional hardware.

For example, we can use four 100Mb ports in each device to form a communication between two switches using 400Mb among them. However, the utilization of redundant enlaces raises the possibility of loops within the network. Link Aggregation avoids the situation which the blocking state or loops, stop the gathered ports, treating them as one single interface. For the STP, SNMP and VLANs the interfaces are treated as one logical link.

Other name used for the Link Aggregation is EtherChannel.

The LACP protocol is part of the 802.3ad specification for Link Aggregation, allowing that switches and servers negotiate the port groups with different manufactures automatically. Both ports should offer constant support to the protocol, so that the Link Aggregation could work correctly.

Some Switch models can utilise the PagP (Cisco) protocol or interface Continue reading

1 … 3,600 3,601 3,602 3,603 3,604 … 3,692