The Case of the Failed IPv6 Ping – Part 1: The Facts and Clues

Put your detective hat on your head and your Network Detective badge on your lapel.   It is time for the Case of the Failed IPv6 Ping.

 

Part #1 –  We hit the crime scene together and we work methodically together to

  • Gather the Facts
  • Collect the Clues
  • Follow the Evidence
  • Interview the Witnesses
  • Question the Suspects

Part #2 – I give you what the problem ended up being.

Ready?  ?  Let’s PLAY!

It all started when I was going to do a post on IPv6 Multicasting. I grabbed 3 ASR1K and got them all prepped: cards, code, cables, configurations. Name the routers R1, R2, and R3. Add a couple Spirent TestCenter ports for traffic and sniffing , configure them, and we are good to go.

ipv6_1

Time for “pre-flight check”, as it were.

  1. PIM neighbors up and running between the routers – CHECK
  2. Make sure that the R3 can ping 2001:db8:14:1::1 – Um……

Oh… crap… that didn’t work.

Let’s go to the active crime scene!

Make sure that the R3 can ping 2001:db8:14:1::

ipv6 ping

ping

no_ping

Well that didn’t work did it? Let’s check the routing table on R3.

ipv6_R3

From R3’s IPv6 routing table we see

  1. R3 Continue reading

Tutorial for small Hadoop cloud cluster LAB using virtual machines and compiling/running first “Hello World” Map-Reduce example project

I had Hadoop experience now for more than a year, thanks to a great series of Cloud Computing courses on Coursera.org, now after ~6 months of running via several cloud systems, I finally have time to put down some of my more practical notes in a form of an article here. I will not go much into theory, my target here would be to help someone construct his first small Hadoop cluster at home and show some of my amateur “HelloWorld” code that will count all words in all works of W. Shakespeare using the MapReduce. This should leave with with both a small cluster and a working compilation project using Maven to expand on your own later …

What I have used for my cluster is a home PC with 32G of RAM to run everything inside using vmWare Workstation. But this guide is applicable even if you run this usingVirtualBox, physical machines, or using virtual machines on some Internet cloud (e.g. AWS/Azure). The point will simply be 4 independent OS linux boxes that are together one a shared LAN to communicate between each other.

Lab Topology

For this one there is not much to say Continue reading

EVPN Inter-VLAN routing + mobility

So in the last blog I essentially looked at one of the most basic aspects of EVPN – a multi-site layer-2 network with nothing fancy going on, with traffic forwarding occurring between multiple sites in the same VLAN. The fact of the matter is that there was nothing going on there that you couldn’t do with a traditional VPLS configuration, however the general idea was to demonstrate the basics and take a look at the basic control-plane first.

In this update we’ll be looking at some of the more exclusive and highly useful aspects of EVPNs which make it a very attractive technology for things such as data-centre interconnect, there are a few things which are possible with EVPN which cannot be done with VPLS.

Consider the revised topology:

Capture

It’s the same topology from the first blog post, however I’ve simply added an additional VLAN (VLAN 101) to ge-0/0/22 of each EX4200 LAN switch, and an additional IXIA host.

For this post we’re going to look at a rather cool way of performing inter-VLAN forwarding between hosts in VLAN100 and VLAN101. Not that I want to spend time teaching people how to suck eggs, but generally in a simple network Continue reading

Systems To Morph As Memory Options Expand

Compute is by far still the largest part of the hardware budget at most IT organizations, and even with the advance of technology, which allows more compute, memory, storage, and I/O to be crammed into a server node, we still seem to always want more. But with a tighter coupling of flash in systems and new memories coming to market like 3D XPoint, the server is set to become a more complex bit of machinery.

To try to figure out what is going on out there with memory on systems in the real world and how future technologies might affect …

Systems To Morph As Memory Options Expand was written by Timothy Prickett Morgan at The Next Platform.

Cisco ASA and Office 365

Office 365 is widely used between many customers. Some of them happen to manage all the Internet connections through a Cisco ASA, not the fancy ASA-X with Firepower, just the plain old 5510. I was asked to allow Office 365 traffic, looks easy huh? Step 1: know your enemy After some Google-fu I found Microsoft […]

Does Aerohive Scale?

AerohiveLogo

Note: If you are a TL/DR type of person, let me give you the short answer to the title of the post: Yes! ?

For everyone else, I will try my hardest to keep this as short as possible. I will include as many pictures and CLI screens as I think are needed to help answer the scalability question, and no more. While I entertained the idea of making two separate posts regarding scalability, I felt it best to keep it to a single post since AP(Access Point) to AP communication and layer 3 roaming are best explained together. My wife and friends will tell you that I can be long-winded. I apologize in advance.

Let me just start by saying that I work for Aerohive Networks. I have been an employee of Aerohive for about 3 months. In that time, I have learned a tremendous amount about the overall Aerohive solution and architecture. Prior to working for Aerohive, I worked for a reseller that sold for Cisco(to include Meraki), Aruba, and Aerohive. I wasn’t unaware of Aerohive, but let’s be honest for a minute. Aerohive doesn’t have a lot of information out there around how their various protocols work. This Continue reading

DynaOptics promises a better lens for smartphone photography

A Silicon Valley startup says it's developed a better lens for smartphone photography -- one that produces clearer images without the distortion often seen in photos from competing lenses.The secret to DynaOptics' Oowa lens is a proprietary manufacturing process that produces what the company calls a freeform lens."What we are able to do with this freeform lens is essentially create a rectangular-like image so that it maps exactly onto the rectangular shape of the image sensor that's in the phone," DynaOptics CEO Li Han Chan said in an interview.To read this article in full or to leave a comment, please click here

5 questions for Apple to answer at WWDC

Apple’s Worldwide Developers Conference is coming to San Francisco next week, giving CEO Tim Cook a chance to get developers fired up over the latest that Apple has to offer.Don’t expect a new iPhone. WWDC is all about software and services, but we'll also get a general update on the state of Apple. Here are some questions Apple needs to answer at the event.How will Siri compete with Cortana and the Google Assistant? When Siri launched in 2011, it was one of the first virtual assistants of its kind, but it now has competitors from Amazon, Microsoft, Facebook and Google. Apple needs to show how Siri is better than — or can at least keep pace with — its rivals.To read this article in full or to leave a comment, please click here

Worth Reading: Radicalizing data collection

Like many Silicon Valley start-ups, Larry Gadea’s company collects heaps of sensitive data from his customers. Recently, he decided to do something with that data trove that was long considered unthinkable: He is getting rid of it. The reason? Gadea fears that one day the FBI might do to him what it did to Apple in their recent legal battle: demand that he give the agency access to his encrypted data. Rather than make what he considers a Faustian bargain, he’s building a system that he hopes will avoid the situation entirely. Washington Post

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NASA describes out of this world data glitch that almost finished its planet hunter

NASA’s highly successful Kepler space telescope has had more than its share of near fatal experiences.The latest happened in April when the spacecraft went into “Emergency Mode” which among other things allows for priority access to ground-based communications via NASA’s Deep Space Network. NASA noted at the time that the spacecraft is nearly 75 million miles from Earth, making the communication slow. Even at the speed of light, it takes 13 minutes for a signal to travel to the spacecraft and back.The spacecraft has since returned to normal function.To read this article in full or to leave a comment, please click here

Industrial control systems vendors get careless about domain squatting

Many companies protect their brands by registering domain names that are slight variations on their own, but manufacturers of industrial control systems don't seem to have followed suit, potentially leaving customers open to attack.Researchers from security consultancy Digital Bond have found 433 so-called "squat" domains whose names are similar to those of 11 industrial manufacturers, and which have been registered by unknown third parties. Some of the domains have been hosting scams, malicious redirects and malware.Attackers engage in domain squatting for various reasons: to host phishing pages in order to steal credentials, direct accidental visitors to malware, profit from the brand's popularity by displaying ads, or sell the domain to the brand owner for a large fee.To read this article in full or to leave a comment, please click here

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