A Fix for Ubuntu Apparently Caching Network Configuration

I’ve been wrestling with an Ubuntu network configuration issue over the last couple of weeks (off and on between working on other projects), and today I finally found a fix for the problem. The issue was that Ubuntu wouldn’t pick up changes to network interfaces. The fix is so simple I’m almost embarrassed to talk about it (it seems like something that I should have known), but I’m posting it here in case others run into the same issue.

Here’s a bit more context: I was switching some of the network interfaces in my Ubuntu 14.04.2 servers from a “standard” network configuration to using VLAN interfaces (after all, it seemed like such a shame to not more fully utilize the 10GbE and 40GbE interfaces in these servers). Before the reconfiguration, the servers had a network interface configuration file (located in /etc/network/interfaces.d and sourced in /etc/network/interfaces) that looked something like this:

auto p55p1
iface p55p1 inet static
address 172.16.3.201
netmask 255.255.255.0

This interface was connected to a port on a Cumulus Linux-powered Dell S6000-ON that was configured as an access port on a particular VLAN. Everything seemed to work just Continue reading

Cisco to Buy Security Firm OpenDNS for $635M

Cisco's security obsession creates an exit for the DNS startup.

Workarounds, kludges, and hacks that will improve your life

Don't let wonky tech get you down!Image by Denimadept/WikipediaLife would be simpler if every piece of technology we dealt with worked in an obvious and straightforward way. Life would also be a lot duller.To read this article in full or to leave a comment, please click here

Testing Open Networking

Over the last couple of weeks, the networking industry has made some significant steps in the right direction, the open networking direction. At the Open Networking Summit (ONS), we heard some great news about the disaggregated network and how open networking is now everywhere from hyperscale to the enterprise to startups to telcos. As exciting as that is, that’s not the news I’m referring to — I’m referring to the announcement of the Open Networking Testing Consortium.

To illustrate why this is big news, I’ll give some background on how open networking has been operating for most people. Up until a few years ago, the way you purchased a bare metal switch was through select APAC sources and a wire transfer. A few weeks later, you’d receive your equipment and it was then up to you, the end user, to perform interoperability testing with your cables and optics manufacturers while on the phone with support, along with bootstrapping your OS to these boxes. Eventually you had both a CapEx and OpEx saving solution that you controlled from end to end.

Luckily for most of you, that experience has now been refined significantly Continue reading

Amazon releases open source cryptographic module

Potentially saving the world from another online security disaster like last year’s Heartbleed, Amazon Web Services has released as open source a cryptographic module for securing sensitive data passing over the Internet.The software, s2n, is a new implementation of Transport Layer Security (TLS), a protocol for encrypting data. TLS is the successor of SSL (Secure Sockets Layer), both of which AWS uses to secure most of its services.The AWS engineers who designed s2n, short for signal-to-noise, reduced the amount of code needed to implement TLS, with the hopes of making it easier to spot potential security vulnerabilities.To read this article in full or to leave a comment, please click here

Docker Machine 0.3.0 Deep Dive

CCIE RSv5 Lab Cram Session & New CCIE RSv5 Mock Labs Now Available

INE CCIE RSv5 Lab Cram Session is now available for viewing in our All Access Pass Library. This course includes over 35 hours of new content for CCIE Routing & Switching Version 5, including both technology review sessions as well as a step-by-step walkthrough of two new CCIE RSv5 Mock Lab Exams. These new Mock Labs are available here as part of INE’s CCIE RSv5 Workbook.

This class is designed as a last minute review of technologies and strategy before taking the actual CCIE RSv5 Lab Exam. Each of the two Mock Labs covered in class are subdivided into three sections – just like the actual exam – Troubleshooting, Diagnostics, and Configuration.

Rack rentals are available for these mock labs here. Technical discussion of the labs is through our Online Community, IEOC.

Happy Labbing!

Cisco plans to buy security-as-a-service provider OpenDNS

Cisco Systems plans to pay $635 million in cash to buy OpenDNS, a company that leverages the Domain Name System (DNS) to provide security services including Web filtering, threat intelligence and malware and phishing protection.The DNS is a core Internet protocol. It’s used to translate Web addresses that are easy for people to remember, like website names, into numerical IP (Internet Protocol) addresses that computers need to communicate with each other.OpenDNS customers configure their computers or networks to use the company’s DNS resolution servers instead of the ones provided by their ISPs and this allows OpenDNS to provide additional services.To read this article in full or to leave a comment, please click here

Network Break 42

Take a Network Break! Grab a coffee, a doughnut and then join us for an analysis of the latest IT news, vendor moves and new product announcements. We’ll separate the signal from the noise–or at least make some noise of our own. Sponsor: Sonus Networks This week’s show was sponsored by Sonus Networks. Sonus wants […]

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AnsibleFest NYC Video Presentations

AnsibleFest in NYC was an amazing day filled with everything Ansible. If you missed the presentations, we've compiled them all here.

FIDO two-factor authentication goes wireless

Expect vendors soon to introduce devices with three forms of wireless support to Fast Identity Online (FIDO) two-factor authentication. The FIDO Alliance today is issuing a new specification for FIDO to support Bluetooth, low-energy Bluetooth (BLE) and near field communications (NFC) wireless technologies in two-factor authentication tokens, according to FIDO Alliance executive director Brett McDowell. That means the alliance recommends that device manufacturers use the spec to start producing and selling these wireless devices.MORE: 10 mobile startups to watch Existing FIDO specs already defined how to make authentication tokens that can be plugged into USB ports. With the new specification these authentication devices would just have to be near a phone, tablet, laptop or desktop that also supports the same wireless technology and is trying to connect with a server that supports FIDO authentication. So devices without USB ports could still authenticate via FIDO.To read this article in full or to leave a comment, please click here

Network Break 42

Take a Network Break! Grab a coffee, a doughnut and then join us for an analysis of the latest IT news, vendor moves and new product announcements. We’ll separate the signal from the noise–or at least make some noise of our own. Sponsor: Sonus Networks This week’s show was sponsored by Sonus Networks. Sonus wants […]

Author information

Greg Ferro

Greg Ferro is a Network Engineer/Architect, mostly focussed on Data Centre, Security Infrastructure, and recently Virtualization. He has over 20 years in IT, in wide range of employers working as a freelance consultant including Finance, Service Providers and Online Companies. He is CCIE#6920 and has a few ideas about the world, but not enough to really count.

He is a host on the Packet Pushers Podcast, blogger at EtherealMind.com and on Twitter @etherealmind and Google Plus.

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The post Network Break 42 appeared first on Packet Pushers Podcast and was written by Greg Ferro.

Cisco and OpenDNS – The Name Of The Game?

This morning, Cisco announced their intent to acquire OpenDNS, a security-as-a-service (SaaS) provider based around the idea of using Domain Naming Service (DNS) as a method for preventing the spread of malware and other exploits. I’ve used the OpenDNS free offering in the past as a way to offer basic web filtering to schools without funds as well as using OpenDNS at home for speedy name resolution when my local name servers have failed me miserably.

This acquistion is curious to me. It seems to be a line of business that is totally alien to Cisco at this time. There are a couple of interesting opportunities that have arisen from the discussions around it though.

Internet of Things With Names

The first and most obivious synergy with Cisco and OpenDNS is around Internet of Things (IoT) or Internent of Everything (IoE) as Cisco has branded their offering. IoT/IoE has gotten a huge amount of attention from Cisco in the past 18 months as more and more devices come online from thermostats to appliances to light sockets. The number of formerly dumb devices that now have wireless radios and computers to send information is staggering.

All of those devices depend Continue reading

RP: OODA

Get Inside the Loop

The post RP: OODA appeared first on 'net work.

Worth Reading: Why We Encrypt

Encryption should be enabled for everything by default, not a feature you turn on only if you’re doing something you consider worth protecting.

The post Worth Reading: Why We Encrypt appeared first on 'net work.

Unlike Uber, more sharing-economy companies are hiring workers as employees

Amidst the battles raging over whether sharing-economy workers should be considered contractors or employees, last week I called for a compromise that would combine the appropriate features of both independent contractors and employees to create a new way to deal with this new kind of business relationship.I still believe that this is the best approach for coping with an emerging class of workers that doesn't fit neatly into either of the existing categories. But what happens until companies, workers, and regulators can strike such a compromise? And what if compromise proves impossible to achieve? Will forcing companies like Uber to actually "hire" its workforce really spell doom for the sharing economy?To read this article in full or to leave a comment, please click here

How to achieve low latency with 10Gbps Ethernet

Good morning!

In a recent blog post we explained how to tweak a simple UDP application to maximize throughput. This time we are going to optimize our UDP application for latency. Fighting with latency is a great excuse to discuss modern features of multiqueue NICs. Some of the techniques covered here are also discussed in the scaling.txt kernel document.

CC BY-SA 2.0 image by Xiaojun Deng

Our experiment will be setup up as follows:

• We will have two physical Linux hosts: the 'client' and the 'server'. They communicate with a simple UDP echo protocol.
• Client sends a small UDP frame (32 bytes of payload) and waits for the reply, measuring the round trip time (RTT). Server echoes back the packets immediately after they are received.
• Both hosts have 2GHz Xeon CPU's, with two sockets of 6 cores and Hyper Threading (HT) enabled - so 24 CPUs per host.
• The client has a Solarflare 10Gb NIC, the server has an Intel 82599 10Gb NIC. Both cards have fiber connected to a 10Gb switch.
• We're going to measure the round trip time. Since the numbers are pretty small, there is a lot of jitter when counting the averages. Instead, it Continue reading

Reading

Reading takes a long time, though, don’t you find? It takes such a long time to get from, say, page twenty-one to page thirty. I mean, first you’ve got page twenty-three, then page twenty-five, then page twenty-seven, then page twenty-nine, not to mention the even numbers. Then page thirty. Then you’ve got page thirty-one and page thirty-three — there’s no end to it. Luckily Animal Farm isn’t that long a novel. But novels . . . they’re all long, aren’t they. I mean, they’re all so long.

The post Reading appeared first on 'net work.

The Upload: Your tech news briefing for Tuesday, June 30

Government personnel agency takes background check system offline for background checksHoping to avoid a third strike against it, the U.S. Office of Personnel Management has taken offline a system used for performing background checks on potential new hires. The agency discovered a security flaw in the web app, E-QIP, while auditing its IT systems after two spectacular hacks resulted in the theft of personnel records of millions of government employees and the security clearance questionnaires of many others. There is no evidence the flaw was exploited, OPM said Monday, but it will keep the system offline for up to six weeks while it checks it out.To read this article in full or to leave a comment, please click here

Push It To The Limit! Understand Wi-Fi’s Breaking Point to Design Better WLANs

This is the fourth and final blog post in the WLAN capacity planning series. Be sure to read the first, second, and third posts.

We all want high performing WLANs. In order to do that we must push Wi-Fi to its limits! 

(Cue Scarface Theme, verse 1)…

We walk a fine line when designing wireless networks, attempting to push as many users and bandwidth through our APs as possible, ensuring adequate capacity is available to meet demand, while not overbuilding the network. But what are the limits and how do we know we’ve hit them? Or more importantly, how do we plan Continue reading