Darkness falls across the land, The hacker hour is close at hand. Creatures crawl in search of 0-days To terrorize your enterprise. And whosoever shall be found, Without the soul for clamping down, Must stand and face the nerds of hell, And rot inside a clear text shell. The foulest stench is in the air, […]
The post Healthy Paranoia Show 10: Beware the Shmoo appeared first on Packet Pushers Podcast and was written by Mrs. Y.
How to study better Exams are a stressful thing to study for—even to the most organised students. Most students are afraid of pulling in a goose egg instead of an A and so they talk themselves out of doing well before they even see the exam. But they don’t really have to; studying in a […]
The post How to Study Better appeared first on Roger Perkin - Networking Articles.
Summary Packet Pushers co-hosts Ethan Banks & Greg Ferro chat with Aneel Lakhani, a research director at Gartner about his job. Aneel provides an insider perspective on how the research & analysis business works. More Info Analyst firm research offerings seem to cynical network engineers like bought-and-paid-for shill pieces whose conclusions follow the money back to its […]
The post Show 137 – Gartner Is Not For Sale with @Aneel Lakhani appeared first on Packet Pushers Podcast and was written by Ethan Banks.
It’s been an exciting couple of weeks in the security realm, with a number of innovative startups appearing. That’s refreshing because recently most “innovation” in the security space has been something involving a new way of marketing a signature or reputation based system – and that’s just a bit rubbish, and not a little tiresome. Most […]
The post NetCitadel and Software Defined Security appeared first on Packet Pushers Podcast and was written by Neil Anderson.
The buzzword in the industry of late is DevOps. It is one that I hope isn’t tarnished by the marketing machine where buzzwords go to die. DevOps is the shift in the paradigm of network and infrastructure management. Centralized infrastructure that is transparent to the administrator and end-user, IaaS, cloud – whatever you want to […]
The post Pull My Strings, I’m Your Puppet: Juniper Bringing DevOps to Networking appeared first on Packet Pushers Podcast and was written by Anthony Burke.
Uplink Fast
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Cisco enhanced the original 802.1D specification with features such as Uplink Fast to speed up the convergence time of a bridged network.
The drawback is that these mechanisms are proprietary and need additional configuration. The UplinkFast feature is a Cisco proprietary technique that reduces the recovery time further down to the order f 1 sec
Normal Scenerio without Uplink fast
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Assume SW1 = Root Bridge
SW3 = access switch with one of its uplinks in blocking mode
Uplink from SW3 to SW2 via port A is primary and SW3 to SW2 via port B is redundant uplink
SW1——————- SW2
– -
– -
– -
– -
-SW3-
suppose uplink SW3 to SW1 fails,port A goes down immediatly.SW3 consider now link to SW2 as its still receiving BPDUs from root,but to get the link to forwrding state ,it will take 30 sec(learning and listening stage) Port B reaches forwarding state after 30 sec qnd network connectivity is established.
Scenerio with Uplink fast
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Note: 1) The switch has only two uplinks.
2) The switch has more than two uplinks, but the STP parameters are set in such way, that Continue reading
Over the weekend I attended the CCDE group study sponsored by INE in Chicago. Discussion and material were let by Petr Lapukhov and Brian McGahan. I’m very excited to see high level networking event in my hometown. We had about 15-20 people in the class. This was my first exposure to CCDE so it was a lot of information absorbing. The test is composed of 4 scenarios. You have about 8 hours to pass the computerized test. Just like in other written Cisco certifications, you can’t go back once you answer the question. The test seems to be based on mastering the design’s information extraction from pages and pages of information. Most of the technology focus is on MPLS, routing, QoS and some security.
In the group study we went through Cisco’s CCDE practice demo (https://learningnetwork.cisco.com/docs/DOC-2438). I thought the discussion was very interested, especially from people that have been studying for the test. If you take it and want to look at the solution you can find it at http://www.shafagh.net/2012/08/ccde-demomystery-solved.html. Next we went through INE’s CCDE practice scenarios written by Petr and Brian.
Mainly, I wanted to post some very interesting documents that Continue reading
Your company has 2 offices that are interconnected via a firewall (Cisco ASA) as shown below. You received the task to configure a BGP session between the border routers but something does not go according to plans.
How does the internet work - We know what is networking
Policy-Based Routing Configuration Here we will show different examples for configure specific PBR types: Enabling PBR on the Router Fast-Switched PBR Local PBR CEF-Switched PBR Enabling PBR This command will define that the router will use PBR and that the PBR will use route-map named TEST. R1(config)# route-map TEST permit 10 Defines a route map […]
We’ve done a few shows now on Ethernet Fabrics where we have been getting deep into the different technology options and different vendor implementations. Avaya has sponsored this show where we actually interview customers who were early adopters of fabric-based and talk about what drove these customers to implement a network fabric, how they went […]
The post Show 136: Avaya – Considerations for Turning your Network into an Ethernet Fabric – Sponsored appeared first on Packet Pushers Podcast and was written by Greg Ferro.
This post represents the solution and explanation for quiz-6. Running dynamic routing protocols over tunnels can result in recursive problems. Read more to understand the problem and some solutions.
