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| Visibility and the software defined data center |
I'm completing a report for InformationWeek where the results suggest that customer have declining interest in converged hardware platforms. Then I noticed this post from Cisco on sales of FlexPod.
The post Musing: Flexpod at $2B Run Rate, VCE at $1.8B – Thats Unexpected appeared first on EtherealMind.
When I first looked at the documentation for ERSPAN I could imagine some uses for it. In some cases it could replace RSPAN, but since it’s only available on Cisco Nexus switches, newer Catalyst 6500s, Cisco ASR routers, and other “high end” devices, I determined that it really had limited uses. But I was wrong. […]
The post ERSPAN – My New Favorite Packet Capturing Trick appeared first on Packet Pushers Podcast and was written by Gary Sckolnick.
The WAN Optimisation market shrank by 12% in Q1. Predictable and unsurprising since WanOp is a enhancing technology that only sells when the market is quiet and stable. Managing WanOp complexity is a problem no one wants.
The post Response: WAN Optimization Market Declines 12 Percent Sequentially Indicating Softening Demand appeared first on EtherealMind.
# run adb as root:
adb root
# connect to the phone over WiFi (the phone's owner had
# already enabled this feature with 'adb tcpip' via USB):
adb connect <phone's wifi ip address>
# check that we get a root shell on the phone:
adb shell 'id'
adb shell '/data/data/lv.n3o.shark/files/tcpdump -c 2'
tcpdump: verbose output suppressed, use -v or -vv for Continue readingIn a previous article I introduced a project for the configuration backups of F5 devices. It offered an automated, centralized backup service for F5 BigIP devices with a web interface. There was also several features mentioned in the road map. Now after 4 months of tireless work, version 3.0 of the Config Backup for F5 […]
The post F5 Configuration Backups 3.0 appeared first on Packet Pushers Podcast and was written by Eric Flores.
====================================The closure summary shows that operators took 8 hour 39 minutes to manually diagnose and remediate the problem with degraded networking infrastructure. The network related outage described in this example is not an isolated incident; other incidents described on this blog include: Packet loss, Amazon EC2 outage, Gmail outage, Delay vs utilization for Continue reading
Closure Summary: On Tuesday, June 24, 2014, at approximately 1:11 PM UTC, engineers received reports of an issue in which some customers were unable to access the Exchange Online service. Investigation determined that a portion of the networking infrastructure entered into a degraded state. Engineers made configuration changes on the affected capacity to remediate end-user impact. The issue was successfully fixed on Tuesday, June 24, 2014, at 9:50 PM UTC.
Customer Impact: Affected customers were unable to access the Exchange Online service.
Incident Start Time: Tuesday, June 24, 2014, at 1:11 PM UTC
Incident End Time: Tuesday, June 24, 2014, at 9:50 PM UTC
=====================================
I'm thinking about writing a book.
Obviously, there are a lot of networking books on the market today. Search for any mainstream certification on Amazon and you'll find titles from half a dozen publishers. The majority of these are oriented toward specific vendors (most commonly Cisco) and many parallel a given certification exam. These books are overall pretty great. Most of them.
There also exists a minority of books which cover topics outside of the vendor-driven mainstream, like Gary A. Donahue's Network Warrior published by O'Reilly, now in its second edition. I love this kind of independent title because its content isn't constrained to a particular mold. The author finds stuff he thinks is relevant and interesting, and he writes about it. This is the correct way to write a book.
But over the past few years it has become painfully evident to me that there are many areas of this field we simply don't talk about in print, at least not at the entry level where perhaps it would be most helpful. If you want a thirty-page lecture on subnetting or a terrible mnemonic for the OSI model, pick any CCNA book from the pile and you're good to Continue reading
Introduction
This post is inspired by a post at IEOC about Uplinkfast and TCN which
can be found here.
Before we get to those parts, let’s recap how Ethernet and STP work together.
Spanning Tree
The Spanning Tree Algorithm builds a loop free tree by comparing Bridge ID(BID) and
least cost paths to the root bridge. By doing this it blocks all links not leading
to the root.
MAC Learning
Switches learn where to forward frames by looking at the source MAC address of the frame
on the port that the frame was received on. This learning is done in the data plane
as opposed to routing where the routes are learned in control plane. I will come back
to this later in the post.
S4 learns that A is located on port 1 after A has sent a frame. This is stored in
the MAC address table located in Content Addressable Memory (CAM). The CAM is a
fast memory optimized for quick lookups in the table. By default there is a 300
second aging timeout for learned MAC addressesm, meaning that if the switch
does not see any traffic from a source MAC within five minutes the entry will
Continue reading
This is “The Coffee Break”. A podcast on state of the networking business where we discuss vendors moves and news, analysis on product and positioning, and look at the business of networking. In the time it takes to have coffee break.
The post Coffee Break – Show 10 appeared first on Packet Pushers.
This is “The Coffee Break”. A podcast on state of the networking business where we discuss vendors moves and news, analysis on product and positioning, and look at the business of networking. In the time it takes to have coffee break. Show Links Cisco Q1 Slump Drops Ethernet Switch Market HP Links SDN, OpenStack […]
The post Coffee Break – Show 10 appeared first on Packet Pushers Podcast and was written by Greg Ferro.
With all of the activity going on in the networking industry right now, and all of the new terminology (as well as old re-invented terminology), it’s quite easy to get messages mixed up. After all, there’s no centralized dictionary for all of this stuff. I’d like to address something that has bugged me for a while.
I’ve now heard from quite a few folks that SDN to them means the ability to automate network tasks. This almost totally misses the point, in my opinion. Network automation should literally be thought of a prerequisite for what we’ll likely be doing on our networks in 10 years; call it SDN if you want. My logic involved with coming to this conclusion is almost 100% about the people involved. Allow me to elaborate.
In my experience the main thing that’s missing from 90% of enterprise networks today is that networking teams have not properly defined their workflows, and/or have not formalized a service catalog to other parts of the business. As a result, everything is fire-fighting, or one-off requests.
Tracking changes historically, and pinning them to business processes is totally impossible (if it’s even attempted), and garbage collection does not occur. Continue reading
We cover all sorts of different topics on this site. Today, we are starting a multipart series on subnetting. These concepts are fundamental building blocks for network administrators, engineers and architects. The subnetting topics outlined in this series should be well understood prior to moving into advanced design or configuration topics. Moreover, the underlying technical concepts of this subject should be understood prior to utilizing any shortcuts to calculate subnet addresses and useable address space.
If I asked this as a multiple choice question, which one of the possible answers would you choose?
If you chose answer B, you are correct. A subnet is a subset of a Classful Network. So the next logical question is, “What is a Classful Network?”
As we answer these questions, we will use “Classful Network” and Network interchangeable. As we move to discussions about subnets, we will explicitly address them as such.
Classful Networks, in TCP/IP terminology are outline in RFC791. It specifically states the following–
Addresses are fixed length of Continue reading
As the infosec community waits for the researchers involved to present their Zeus Gameover take down spoils at the next big conference; ASERT wanted to profile a threat actor that uses both Citadel, “a particularly sophisticated and destructive botnet”, and Gameover, “one of the most sophisticated computer viruses in operation today”, to steal banking credentials.
Citadel Campaign
When a threat actor decides that they would like to start a Citadel campaign they: buy the builder software, build the malware, distribute it to the wild, and then, unfortunately, usually profit. A “login key” in Citadel parlance identifies a specific copy of the builder. This key is also copied into the generated binaries so a link between malware builder and malware is formed. Login keys are supposed to be unique, but due to builders being leaked to the public, some aren’t. For all intents and purposes though, malware researchers use login keys to distinguish between distinct Citadel campaigns.
On October 29, 2013, security researcher Xylitol tweeted that login key 5CB682C10440B2EBAF9F28C1FE438468 was not associated with any of the defendants in Microsoft’s Citadel botnet lawsuit:
ASERT has the following command and control (C2) URLs linked with that campaign. Most Continue reading
SDN/NFV Management and Orchestration
At last week’s Big Telecom Event in Chicago, Caroline Chappell, senior analyst with Heavy Reading (the sister organization of Light Reading) moderated a panel discussion on SDN/NFV Management and Orchestration. Readers of this blog will know that’s a subject near and dear to us at Packet Design, and Cengiz Alaettinoglu, our CTO, was a member of the panel. He was joined by speakers from Infoblox, Overture, UBIqube, and NTT America.
Packet Design CTO, Cengiz Alaettinoglu, speaks at the BTE Conference
Ms. Chappell opened the discussion by posing the question, “How real is SDN/NFV, and how quickly will network operators move from proofs of concept to production deployments?” In keeping with what we had heard in earlier conference keynotes and panel sessions, Doug Junkins with NTT America, the only operator on this panel, stated they are already implementing SDN/NFV in 50 data centers globally. He said the primary business drivers are: (1) driving down the cost of provisioning services and (2) new services creation. When asked how NTT views SDN in the context of NFV, he explained that they use the term network automation in Continue reading
