In Part 1 we discussed how to turn off ISATAP on Windows host—which is a great idea. Turning off unnecessary components of your network simplifies everything. But ISATAP can be useful in certain scenarios. For instance, if you want to test an application on IPv6 you clearly don’t want to turn on IPv6 everywhere and […]
The post Windows ISATAP Client, Part 2 appeared first on Packet Pushers Podcast and was written by Dan Massameno.
I've been reading the Cisco Application Centric Infrastructure Design Guide. Sometimes I see a product of genius and wondrous use of technology, other times I'm like 'did they do it the hard way or what' ?
The post Musing: First thoughts on how Cisco ACI Works appeared first on EtherealMind.
Here’s an interesting story illustrating the potential pitfalls of multi-DC deployments and the impact of data gravity on application performance.
Long long time ago on a cloudy planet far far away, a multinational organization decided to centralize their IT operations and move all workloads into a central private cloud.
Read more ...
@revolutionwifi @vall_wifi @KeithRParsons The negative effects on effective range with wider channels http://t.co/wyg3qtQjJl
— George Ou (@GeorgeOu) August 20, 2014
Today we are very happy to announce DockerCon Europe 2014, the first official Docker conference organized in Europe, by both Docker, Inc. and members of the community. The conference will take place in Amsterdam, at the NEMO science center, December 4th and 5th.
We will also have a full day or training prior to the conference, led by Jérôme Petazzoni on December 3rd.
The official website is still under construction as we are finalizing the last details, but today we can announce that the Docker team will be present as well as incredible speakers from the Docker community including:
Call for papers opens today, you can submit your talk here. If you are interested in our sponsorship options, please contact us at [email protected].
We also want to give a special thanks to Pini Reznik, Harm Boertien, Mark Coleman, Maarten Dirkse and the Docker Amsterdam community, who are working with us to bring the best of Docker to Europe.
Save the dates and stay tuned for more announcements!
In this post I will be showing you how its possible to use different paths between your PE routers on a per VRF basis.
This is very useful if you have customers you want to “steer” away from your normal traffic flow between PE routers.
For example, this could be due to certain SLA’s.
I will be using the following topology to demonstrate how this can be done:
A short walkthrough of the topology is in order.
In the service provider core we have 4 routers. R3, XRv-1, XRv-2 and R4. R3 and R4 are IOS-XE based routers and XRv-1 and XRv-2 are as the name implies, IOS-XR routers. There is no significance attached to the fact that im running two XR routers. Its simply how I could build the required topology.
The service provider is running OSPF as the IGP, with R3 and R4 being the PE routers for an MPLS L3 VPN service. On top of that, LDP is being used to build the required LSP’s. The IGP has been modified to prefer the northbound path (R3 -> XRv-1 -> R4) by increasing the cost of the R3, XRv-2 and R4 to 100.
So by default, traffic between Continue reading
SDN evangelists talking about centralized traffic engineering, flow steering or bandwidth calendaring sometimes tend to gloss over the first rule of successful traffic engineering: Know Thy Traffic.
In a world ruled by OpenFlow you’d expect the OpenFlow controller to know all the traffic; in more traditional networks we use technologies like NetFlow, sFlow or IPFIX to report the traffic statistics – but regardless of the underlying mechanism, you need a tool that will collect the statistics, aggregate them in a way that makes them usable to the network operators, report them, and potentially act on the deviations.
Read more ...
Tower 2.0 is our biggest release so far, and focuses on supercharging the day to day Ansible experience -- creating the best possible environment for a team using Ansible. It completely revolutionizes the way Ansible playbooks are experienced. New features in Ansible Tower’s 2.0 release include:
Continue reading |
| Typical Wi-Fi SNR to MCS Data Rate Mappings (Download for full resolution Continue reading |
I want the speed and other advantages of a static site generator, but with the flexibility of a database-backed CMS.
From cars to computers, getting both flexibility and performance all too often requires a carefully weighed set of trade-offs. Generating content for your readers and fans on the web is no exception. On the one hand, techies have recently embraced static site generators such as Jekyll, and for good reason, as these systems provide a lot of advantages (e.g., deploying straight to Github pages, high performance, and ease of keeping your content in version control). However, they are not without their own challenges such as steep learning curves and slow, cumbersome workflows.
On the other hand, flexible, database-backed content management system such as WordPress can be a better choice in some situations. It’s very nice to have the flexibility to allow non-technical people to edit and update content, and for authors to edit online from anywhere without needing a special suite of software and skills. However, CMSs such as WordPress can also be slow, temperamental, and hard to optimize.
Lately, I’ve been trying to find a good balance for my website. Currently, it Continue reading
As part of my work in OpenDaylight, we are looking at creating a router using Open vSwitch... Why? Well OpenStack requires some limited L3 capabilities and we think that we can handle those in a distributed router.
As part of my work in OpenDaylight, we are looking at creating a router using Open vSwitch... Why? Well OpenStack requires some limited L3 capabilities and we think that we can handle those in a distributed router.
My test topology looks like this:
We have a host in an external network 172.16.1.0/24, one host in an internal network 10.10.10.0/24 and two hosts in another internal network 10.10.20.0/24.
As such, The hosts in the 10.x.x.x range should be able to speak to each other, but should not be able to speak to external hosts.
The host 10.10.10.2 has a floating IP of 172.16.1.10 and should be reachable on this address from the external 172.16.1.0/24 network. To do this, we'll use DNAT for traffic from 172.16.1.2 -> 172.16.1.10 and SNAT for traffic back from 10.10.10.2 -> 172.16.1.2
If you'd like to recreate this topology you can checkout the OpenDaylight OVSDB project source on GitHub and:
vagrant up mininet
vagrant ssh mininet
cd /vagrant/resources/mininet
sudo mn --custom Continue readingOriginal design manufacturers (ODMs) and bare metal networking vendors were relatively unknown entities. Pricing and product availability was obscure or difficult to ascertain. The supply chain for bare metal networking was non-existent. (You can read more about The Modern Networking Supply Chain and the Death of the Multiplier Effect.) Consequently, mega-scale operators deployed solutions, procured directly from ODMs in lots of hundreds to thousands.
Today, bare metal networking is available to the mass market around the world.
The Open Network Install Environment, ONIE, is a fundamental enabler to bare metal networking. ONIE is an Open Compute Project (OCP, pioneered by Facebook) initiative facilitating any network operating system to be installed (or removed) on any ONIE-based switch. Bare metal networking vendors have adopted ONIE en masse, simplifying operations for distributors and resellers with a minimum number of hardware SKUs, in parallel, making the simplified supply chain available to a range of software suppliers. Today, there are approximately 20 ONIE-based platforms in flexible Continue reading
Multicast hasn’t been a hot topic in networking in recent years, but that may be changing with last week’s announcements by both AT&T and Verizon that they will launch LTE multicast in 2015. Verizon plans to start embedding the technology in phones in the fourth quarter of this year and commercially launch the service in 2015. AT&T will also begin to roll out multicast capabilities next year.
According to Verizon CFO Fran Shammo, multicast is “…the pivotal point that starts to change the way content is delivered over a mobile handset which opens up content into the wireless world."
As Humberto Saabedra explains in an article for PhoneNews.com: “LTE Multicast allows the same content to be sent to a large number of subscribers at the same time, resulting in a more efficient use of network resources than each user requesting the same content and then having the content individually streamed to each user.”
Currently, organizations use multicast for multimedia distribution, desktop imaging, market trading data distribution, broadcast video, online education, and other purposes where data must be delivered simultaneously to multiple receivers. Packet Continue reading
There’s a new term floating around that seems to be confusing people left and right. It’s something that’s been used to describe a methodology as well as used in marketing left and right. People are using it and don’t even really know what it means. And this is the first time that’s happened. Let’s look at the word “open” and why it has become so confusing.
Talking Beer
For those at home that are familiar with Linux, “open” wasn’t the first term to come to mind. “Free” is another word that has been used in the past with a multitude of loaded meanings. The original idea around “free” in relation to the Open Source movement is that the software is freely available. There are no restrictions on use and the source is always available. The source code for the Linux kernel can be searched and viewed at any time.
Free describes the fact that the Linux kernel is available for no cost. That’s great for people that want to try it out. It’s not so great for companies that want to try and build a business around it, yet Red Hat has managed to do just that. How can they Continue reading
A visual representation of the company and, to a lesser extent, product history of the load balancing/application delivery field. My usual F5 bias is present but it seems justified considering their long-held market leading position. I’ve been itching to post this for a while but simply couldn’t stop changing the formatting. I can’t say I’m […]
The post A History of Load Balancing appeared first on Packet Pushers Podcast and was written by Steven Iveson.
The Raspberry Pi was created with a simple mission in mind: change the way people interact with computers. This inexpensive, credit card-sized machine is encouraging people, especially kids, to start playing with computers, not on them.
When the first computers came out, basic programming skills were necessary. This was the age of the Amigas, BBC Micros, the Spectrum ZX, and Commodore 64s. The generation that grew up with these machines gained a fundamental understanding how how computers work.
Computers today are easy to use and require zero understanding of programming to operate. They’re also expensive, and wrapped in sleek cases. While aesthetically pleasing designs and user friendly interfaces make computers appealing and accessible to everyone, these advances create a barrier to understanding how computers work and what they are capable of doing. This isn’t necessarily a problem, but for those who really understand computers, it seems that our collective sense of the power of computing has been dulled.
Raspberry Pi marks the beginning of a conscious effort to return to computing fundamentals. Starting at about $25—case not included—it’s purposely designed to remove barriers to tinkering, reprograming, and, ultimately, to understanding how computers work. This return to fundamentals is rejuvenating the Continue reading
I’m still getting questions about layer-2 data center interconnect; it seems this particular bad idea isn’t going away any time soon. In the face of that sad reality, let’s revisit what I wrote about layer-2 DCI over VXLAN.
VXLAN hasn’t changed much since the time I explained why it’s not the right technology for long-distance VLANs.
Read more ...Are you familiar with the Go programming language and looking for a job in San Francisco or London? Then think about applying to CloudFlare. We're looking for people with experience writing Go in both locations.
CC BY-SA 2.0 by Yuko Honda (cropped, resized)
CloudFlare uses Go extensively to build our service and we need to people to build and maintain those systems. We've written a complete DNS server in Go, our Railgun service is all Go and we're moving more and more systems to Go programs.
We've recently written about our open source Red October Go project for securing secrets, and open-sourced our CFSSL Go-based PKI package. Go is now making its way into our data pipeline and be used for processing huge amounts of data.
We even have a Go-specific section on our GitHub.
If you're interested in working in Go on a high-performance global network like CloudFlare, send us an email.
Not into Go? We're hiring for all sorts of other positions and technologies.
As part of my work in OpenDaylight, we are looking at creating a router using Open vSwitch... Why? Well OpenStack requires some limited L3 capabilities and we think that we can handle those in a distributed router.
