Identifying bad ECMP paths

In the talk Move Fast, Unbreak Things! at the recent DevOps Networking Forum,  Petr Lapukhov described how Facebook has tackled the problem of detecting packet loss in Equal Cost Multi-Path (ECMP) networks. At Facebook's scale,  there are many parallel paths and actively probing all the paths generates a lot of data. The active tests generate over 1Terabits/second of measurement data per Facebook data center and a Hadoop cluster with hundreds of compute nodes is required per data center to process the data.

Processing active test data can detect that packets are being lost within approximately 20 seconds, but doesn't provide the precise location where packets are dropped. A custom multi-path traceroute tool (fbtracert) is used to follow up and narrow down the location of the packet loss.

While described as measuring packet loss, the test system is really measuring path loss. For example, if there are 64 ECMP paths in a pod, then the loss of one path would result in a packet loss of approximately 1 in 64 packets in traffic flows that cross the ECMP group.

Black hole detection describes an alternative approach. Industry standard sFlow instrumentation embedded within most vendor's switch hardware provides visibility into the Continue reading

Google’s new tools make it easier to integrate apps with its spreadsheets and slides

Google is updating the developer tools for its Docs productivity suite in an effort to make it easier for companies to integrate third-party applications with its presentation, spreadsheet and word processing software. Software makers can start working with a new tool that lets them sync data between a Google Sheet and their application for easy data compilation and sharing among people who use the online spreadsheet software. In addition, Google also announced a new Slides API that will allow users to automatically populate slide decks with information from outside sources. Software packages like Google Docs don't exist in a vacuum, and offering developers a way to more deeply integrate with the company's products could lead to more companies becoming interested in picking up the productivity suite because of how it works with other software. To read this article in full or to leave a comment, please click here

Google’s new tools make it easier to integrate apps with its spreadsheets and slides

Google is updating the developer tools for its Docs productivity suite in an effort to make it easier for companies to integrate third-party applications with its presentation, spreadsheet and word processing software.  Software makers can start working with a new tool that lets them sync data between a Google Sheet and their application for easy data compilation and sharing among people who use the online spreadsheet software. In addition, Google also announced a new Slides API that will allow users to automatically populate slide decks with information from outside sources.  Software packages like Google Docs don't exist in a vacuum, and offering developers a way to more deeply integrate with the company's products could lead to more companies becoming interested in picking up the productivity suite because of how it works with other software. To read this article in full or to leave a comment, please click here

IDG Contributor Network: Will programmers in health IT have to take the Hippocratic Oath?

In the health IT development hype cycle, a number of novel technologies have been announced and marketed. One example is the Qualcomm Tricorder Xprize, which is a competition designed to encourage developers to build a device that will diagnosis and self-treat a number of chronic conditions without the need for a physician. This prize is from the same organization (Xprise) that tried to encourage suborbital flight from commercial spacecraft companies.Technology is so pervasive in healthcare that books have been written about “The Internet of Health Things” (Kvedar J.C., The Internet of Healthy Things) that describe the wonderful new sensors patients can wear and measure their health every day. Even within older data collection paradigms, the healthcare area is talking about patient-reported outcomes and how we need to incorporate this data with the electronic health record to help improve patient care.To read this article in full or to leave a comment, please click here

Faced with a bunch of obstacles, this robot got creative and surprised its makers

Dealing with obstacles is an inevitable part of life, and it looks like robots may be surprisingly adept at applying creativity to the challenge.Researchers from Carnegie Mellon University developed software that not only helped a robot deal efficiently with clutter but also revealed considerable creativity in solving problems. Their new study is due to be presented Thursday at the IEEE International Conference on Robotics and Automation in Sweden.A research team led by Siddhartha Srinivasa, CMU associate professor of robotics, challenged HERB -- his lab's two-armed mobile robot -- with a pile of clutter.To read this article in full or to leave a comment, please click here

Nokia-branded Android phones will return to the market

Get ready for new Nokia Android phones. No, Nokia isn’t coming back. Instead a group of former Microsoft executives have formed a company called HMD global, which will use Nokia branding in a new line of Android smartphones and tablets.HMD signed an agreement with Nokia Technologies which allows the brand licensing. This will certainly give the new devices a higher profile than if they were under an unknown label.The Helsinki-based HMD didn’t offer any specifics about when such phones and tablets would launch or what the pricing would be. The move further distances Nokia from Microsoft (whose own future with Lumia devices is rather uncertain). To read this article in full or to leave a comment, please click here

10 ways law firms can make life difficult for hackers

In the world of cybercrime, everybody from individuals to nation states is a target – some more attractive than others, of course. Health care organizations have gotten the most headlines recently, and the Internet of Things (IoT) offers an almost unlimited attack surface.But law firms are attractive too. They hold sensitive, confidential data ranging from the personal (divorce, personal injury) to the professional (contract negotiations, trade secrets, mergers and acquisitions, financial data and more) that, if compromised, could cause catastrophic damage both to the firm and its clients.To read this article in full or to leave a comment, please click here

10 ways law firms can make life difficult for hackers

In the world of cybercrime, everybody from individuals to nation states is a target – some more attractive than others, of course. Health care organizations have gotten the most headlines recently, and the Internet of Things (IoT) offers an almost unlimited attack surface.But law firms are attractive too. They hold sensitive, confidential data ranging from the personal (divorce, personal injury) to the professional (contract negotiations, trade secrets, mergers and acquisitions, financial data and more) that, if compromised, could cause catastrophic damage both to the firm and its clients.To read this article in full or to leave a comment, please click here

Microsoft issues cumulative roll-up pack for Windows 7

Microsoft yesterday threw a bone to Windows 7 users by releasing a cumulative roll-up that collects all the bug fixes from February 2011 to April 2016, making it easier to update a PC running the still-standard OS. The Redmond, Wash. company has ditched the "service pack" moniker, and so named Tuesday's collection a "convenience rollup update." The label was meaningless, however: The update was identical to a service pack. "This convenience rollup is intended to make it easy to integrate fixes that were released after SP1 for Windows 7 and Windows Server 2008 R2," Microsoft said in a document explaining the update.To read this article in full or to leave a comment, please click here

Google announces Google Home, bringing ‘OK Google’ to your kitchen

Google confirmed that it will have an Amazon Echo competitor, called Google Home. Announced during the keynote of Google I/O 2016, Home will serve as a hardware avatar of sorts for its new Google Assistant conversational language search tool.Google Home will be available later this year, executives said, for an undisclosed price. The company showed off the small, cylindrical device in white, but it will feature bases in custom colors. Google Home being held by Mario Queiroz, vice president of product management and a member of the Chromecast team.To read this article in full or to leave a comment, please click here

Mobile app FurAlert helps find missing pets through alerting

If you’ve ever had a pet go missing from your house, you know that time is critical – whether it’s danger from other animals or the possibility of them getting hit by a car, you want to find them quickly.Here’s a really cool tool - the FurAlert app, available for iOS and Android smartphones, gets the word out quickly to other FurAlert users when a pet goes missing. The app serves two purposes – it lets pet owners alert all of the other users (within a specific geographic area) if a pet goes missing. Second, it lets someone who has found the animal notify the pet’s owner directly, through a phone call, text or email.To read this article in full or to leave a comment, please click here

Universal Scaling and Complexity

The universal scaling law is a model designed to help engineers understand transaction based systems, particularly databases and applications. What could a transaction based system have to do with network design? After all, networks aren’t really transaction based, are they? Or maybe they are…

complexity-modelLet’s ignore the data flowing through the network for a moment (though the universal scaling law might provide an interesting way to look at packets or flows per second as transactions), and focus just on the control plane. When we look at the control plane, we find a routing protocol or a centralized controller that accepts information about changes in the network topology (and other data points), and builds a model of the network topology which can be used to forward traffic. Questions we can ask about the state being handled by the control plane include things like: How many changes are there? What is the rate at which this information arrives? How many changes might be present in the system at any given time? How many devices participate in the control plane?

If these all sound like questions about state, one of the three “legs” of the complexity model (state, optimization, surface), that’s because they Continue reading

IDG Contributor Network: The shift in open source: A new kind of platform war

For many years, open source software seemingly lay at the fringe of the tech industry. A subculture that many didn’t understand and that seemingly threatened the broader industry. It is amazing how much has changed.Today, open source software, especially Linux, is so pervasive that you probably interact with it every day. From supercomputers to GoPros and nearly every data center in the world, open source software is the default platform.+ More on Network World: Open source: Career-maker, or wipeout? +Not only does almost every company (and government agency) leverage open source software in some capacity, but even vendors who fought it tooth and nail have finally turned around. Microsoft’s embrace of open source software under Satya Nadella is a great example of the massive change in perception that has been slowly creeping over the industry over the past 20 years.To read this article in full or to leave a comment, please click here

In-Memory Breathes New Life Into NUMA

Hyperscalers and the academics that often do work with them have invented a slew of distributed computing methods and frameworks to get around the problem of scaling up shared memory systems based on symmetric multiprocessing (SMP) or non-uniform memory access (NUMA) techniques that have been in the systems market for decades. SMP and NUMA systems are expensive and they do not scale to hundreds or thousands of nodes, much less the tens of thousands of nodes that hyperscalers require to support their data processing needs.

It sure would be convenient if they did. But for those who are not hyperscalers,

In-Memory Breathes New Life Into NUMA was written by Timothy Prickett Morgan at The Next Platform.

Cisco WLC roaming troubleshooting scripts

As it often happens, everything begins with a call from a customer with a problem. The problem is related to WiFi roaming in a warehouse with clients disconnecting from RDP sessions. The clients are industrial PCs installed on forklifts that move quite fast (and dangerously). Second rule of troubleshooting: measure As the first rule is […]