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Category Archives for "Networking"

Community Show – CCNA Data Center Part1 with Anthony Sequeira and Orhan Ergun

In this first part of CCNA Datacenter sessions , Anthony Sequeira and Orhan Ergun are talking about the topics in the blueprint. They identify all the technologies which you should know for the CCNA Datacenter exam. Topics include : DCICN exam which is the first exam. DCICT exam which is the second exam. Datacenter Fundamentals, […]

Author information

Orhan Ergun

Orhan Ergun, CCIE, CCDE, is a network architect mostly focused on service providers, data centers, virtualization and security.

He has more than 10 years in IT, and has worked on many network design and deployment projects.

In addition, Orhan is a:

Blogger at Network Computing.
Blogger and podcaster at Packet Pushers.
Manager of Google CCDE Group.
On Twitter @OrhanErgunCCDE

The post Community Show – CCNA Data Center Part1 with Anthony Sequeira and Orhan Ergun appeared first on Packet Pushers Podcast and was written by Orhan Ergun.

Community Show – CCNA Data Center Part1 with Anthony Sequeira and Orhan Ergun

[player] In this first part of CCNA Datacenter sessions , Anthony Sequeira and Orhan Ergun are talking about the topics in the blueprint. They identify all the technologies which you should know for the CCNA Datacenter exam. Topics include : DCICN exam which is the first exam. DCICT exam which is the second exam. Datacenter […]

The post Community Show – CCNA Data Center Part1 with Anthony Sequeira and Orhan Ergun appeared first on Packet Pushers.

A Quick Look at MPLS-TE

Introduction

I’m currently designing and implementing a large network which will run MPLS.
This network will replace an old network that was mainly L2 based and did not
run MPLS, only VRF lite. There are a few customers that need to have diverse
paths in the network and quick convergence when a failure occurs.
This led me to consider MPLS-TE for those customers and to have plain MPLS
through LDP for other customers buying VPNs. What is the usage for MPLS-TE?

Weaknesses of IGP

When using normal IP forwarding a least cost path is calculated through an IGP,
such as OSPF or ISIS. The problem though is that only the least cost path will
be utilized, any links not on the best path will sit idle, which is a waste of
bandwidth. IGP metrics can be manipulated but that only moves the problem to
other links, it does not solve the root cause. Manipulating metrics is cumbersome
and prone to error. It’s difficult to think of all the traffic flows in the network
and get all the metrics correct. IGPs also lack the granularity in metrics to
utilize all the bandwidth in the network.

RSVP-TE

RSVP in the past was Continue reading

Finally: a Virtual Switch Supports BPDU Guard

Nexus 1000V release 5.2(1)SV3(1.1) was published on August 22nd (I’m positive that has nothing to do with VMworld starting tomorrow) and I found this gem in the release notes:

Enabling BPDU guard causes the Cisco Nexus 1000V to detect these spurious BPDUs and shut down the virtual machine adapters (the origination BPDUs), thereby avoiding loops.

It took them almost three years, but we finally have BPDU guard on a layer-2 virtual switch (why does it matter). Nice!

Response – Do We Need To Redefine Open?

Tom Hollingsworth wrote a great post on whether or not we need to redefine "Open". My response was too long for a comment, so here it is!

Open Source vs Free Software

The first item is just a point of clarification. While the terms "Open Source" and "Free Software" are often used interchangeably there is a difference.

The two terms describe almost the same category of software, but they stand for views based on fundamentally different values. Open source is a development methodology; free software is a social movement. - Richard Stallman

You can read the full article here but the TL;DR version is that while a high percentage of Open Source software is Free Software, the definition of Open Source is less strict about guaranteeing freedoms.

...with that out of the way, let's move to "open"

On "open" and "openness"

I like the Wikipedia description of "openness":

Openness is an overarching concept or philosophy that is characterized by an emphasis on transparency and free unrestricted access to knowledge and information as well as collaborative or cooperative management and decision making rather than a central authority. - Wikipedia

It highlights some key terms which our "open" things should be adhering Continue reading

Fun with Fig (and Docker)

I first heard of Fig when I read about Docker acquiring Orchard, a container hosting service, back in July. Last week I finally got to read a little more about it and it just so happens it is the missing piece of the puzzle in a couple of projects that I am working on right now!

What does Fig do?

The best way I would describe Fig is like Vagrant for Docker containers. If you don't know what Vagrant is, or aren't using it then you are missing out!

Fig lets you bring up and tear down docker containers (single or multiple) with a simple command. To do this, you express the desired configuration in a YAML file, fig.yml.

Getting started

On OSX, you'll need to have an accessible Docker environment. The easiest way to do this is with Homebrew and boot2docker

brew install docker
brew install boot2docker
boot2docker init
boot2docker start
export DOCKER_HOST=tcp://$(boot2docker ip 2>/dev/null):2375
# Install Fig
pip install fig

If you don't have Python and/or pip installed you may want to install the fig binary

Writing a Fig file for Open vSwitch

Let's say you are doing some integration Continue reading

Vocus Acquisition of FX: Good for Customers?

Consolidation is happening in the New Zealand wholesale ISP market, with Vocus acquiring FX. Consolidation can lead to less competition, or it can strengthen it, by making players stronger and more viable. This acquisition should strengthen the market, and hopefully open up new service offerings.

In July Vocus Communications announced its intention to acquire FX Networks. From the press release:

FX owns a unique and high quality fibre optic network consisting of 4,132 kms of modern ducted fibre cable covering both the North and South Islands of New Zealand. The company has 365 customers including 43 of the Top 100 companies in New Zealand.

Vocus will acquire FX for an enterprise value of NZ$115.8m (~A$107.7m). The FX business is expected to deliver NZ$13.5-$14.5m of EBITDA in the first 12 months post acquisition (excluding transaction and integration expenses).

The combination of Vocus and FX strengthens both businesses. Vocus will emerge as the third largest network operator in NZ and the clear leader in trans-Tasman telecommunications and data centres.

Vocus has their own fibre network around Australia, and has a significant international network, with high-level peering. In 2012 they purchased Maxnet, a New Zealand ISP and Data Center Continue reading

ipSpace.net Is on CloudFlare (and IPv6)

After a week of testing, I decided to move the main ipSpace.net web site (www.ipspace.net) as well as some of the resource servicing hostnames to CloudFlare CDN. Everything should work fine, but if you experience any problems with my web site, please let me know ASAP.

2014-08-27: Had to turn off CloudFlare (and thus IPv6). They don't seem to support HTTP range requests, which makes video startup time unacceptable. Will have to move all video URLs (where the HTTP range requests are expected coming from streaming clients) to a different host name, which will take time.

Collateral benefit: ipSpace.net is now fully accessible over IPv6 – register for the Enterprise IPv6 101 webinar if you think that doesn’t matter ;)

Useful Links — Cisco Quicklinks

I just wanted to take a quick moment to share a site Dan DeBusschere has created. This site is a list of very useful config snippets, information and links. Most of the content is focused on Datacenter and UCS. If you support this type of environment, check it out.

Disclaimer: This article includes the independent thoughts, opinions, commentary or technical detail of Paul Stewart.  This may or may not reflect the position of past, present or future employers. 

No related content found.

The post Useful Links — Cisco Quicklinks appeared first on PacketU.

What is an Automatic Transfer Switch (Power)?

In response to the power redundancy article I wrote yesterday, a few comments came in. One of them (thanks, Mike!) mentioned an automatic transfer switch (ATS), a useful tool in a redundant power strategy. What is an ATS? There are many types of electrical transfer switches whose primary purpose is to divert the […]

Missing Synergies & HP’s SDN

As someone who’s been monitoring HP’s SDN strategy for years now, news that Bethany Mayer is headed to Ixia is rather interesting. Despite HP’s networking division having had some successes and gaining small bits of market share here and there, the fact they they are leaders in the SDN space seems to go unnoticed by the […]