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Cisco UCS ASCII Art

A while back I wrote about the problems with using some of the newer 3rd generation blade hardware from Cisco with older generations of the chassis FEX/IOM. Because of the way that the VIC and the chassis IOM interact, certain combinations yield different amounts of aggregate bandwidth, and certain combinations don’t work at all, as was evidenced in that post. As a reminder, here are the valid combinations (these are still accurate to my knowledge, but may change in a few weeks if any new tech is announced at Cisco Live) of FEX and blade VIC:

Cisco UCS ASCII Art

A while back I wrote about the problems with using some of the newer 3rd generation blade hardware from Cisco with older generations of the chassis FEX/IOM. Because of the way that the VIC and the chassis IOM interact, certain combinations yield different amounts of aggregate bandwidth, and certain combinations don’t work at all, as was evidenced in that post. As a reminder, here are the valid combinations (these are still accurate to my knowledge, but may change in a few weeks if any new tech is announced at Cisco Live) of FEX and blade VIC:

[Code] PowerTool: PowerOnUCSBlades

InstallBFS.ps1 # # Very brief and informal PowerShell script to configure a Boot-From-SAN policy and attach it to the relevant service profile templates. Import-Module CiscoUcsPs Disconnect-Ucs Connect-Ucs 10.0.0.1 $organization = "SUBORG_01" #Add Boot Policies $bp = Add-UcsBootPolicy -Org $organization -Name "BFS-ESX-PROD" -EnforceVnicName yes $bp | Add-UcsLsBootVirtualMedia -Access "read-only" -Order "1" $bootstorage = $bp | Add-UcsLsbootStorage -ModifyPresent -Order "2" $bootsanimage = $bootstorage | Add-UcsLsbootSanImage -Type "primary" -VnicName "ESX-PROD-A" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "primary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "secondary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage = $bootstorage | Add-UcsLsbootSanImage -Type "secondary" -VnicName "ESX-PROD-B" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "primary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "secondary" -Wwn "50:00:00:00:00:00:00:00" $bp = Add-UcsBootPolicy -Org $organization -Name "BFS-ESX-NONP" -EnforceVnicName yes $bp | Add-UcsLsBootVirtualMedia -Access "read-only" -Order "1" $bootstorage = $bp | Add-UcsLsbootStorage -ModifyPresent -Order "2" $bootsanimage = $bootstorage | Add-UcsLsbootSanImage -Type "primary" -VnicName "ESX-NONP-A" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "primary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "secondary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage = $bootstorage | Add-UcsLsbootSanImage -Type "secondary" -VnicName "ESX-NONP-B" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "primary" -Wwn "50:00:00:00:00:00:00:00" $bootsanimage | Add-UcsLsbootSanImagePath -Lun 0 -Type "secondary" -Wwn "50:00:00:00:00:00:00:00" $bp = Add-UcsBootPolicy -Org $organization -Name Continue reading

Why I switched from MultiMarkdown to Pandoc

For the last 6 months I've been using Markdown where I can. Since embarking on the path towards a more Agile approach to writing, it has been necessary to use Markdown more and more. This has led me towards using Pandoc Markdown rather than MultMarkdown as my dialect of choice and I hope to explain why.

So what's so good about Markdown?

If you haven't used Markdown already, you might be wondering what the fuss is about. Basically it is a way of writing markup in an easy-to-read, easy-to-write fashion. It decouples the act of writing from formatting/layout so the same source text can be used to produce multiple formats.

Barriers to Markdown adoption

So what are the barriers to Markdown adoption? Personally I have found only two.

While I use Markdown, the rest of the company uses Microsoft Word - All of our corporate templates are in MS Word format - Neither Markdown or MultiMarkdown reliably export to MS Word format (yes MMD does ODF, but it doesn't handle images well)

The next issue is that Markdown to PDF conversion uses LaTeX. Unfortunately I neither have the time nor inclination to learn LaTeX. While it can be a powerful Continue reading

Show 150 – Self Congratulations, CLUS and Career Advice

Thanks to everyone who supports Packet Pushers and supports us. We could not do this without you. Greg & Ethan go solo to talk a little about 150 weekly shows  Cisco Live US 2013 – Tweet UP – http://networkingnerd.net/2013/05/23/cisco-live–2013-tweetup/ Greg has Published an eBook Greg wrote an eBook on blogging – The Arse First Guide to Technical […]

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.

The post Show 150 – Self Congratulations, CLUS and Career Advice appeared first on Packet Pushers Podcast and was written by Greg Ferro.

Using Pandoc with Marked app

I recently changed from MultiMarkdown to Pandoc. But I still wanted to use Marked app to preview my work…

Thankfully the author of Marked allowed for such an eventuality with the "Custom Processor" option.

Pandoc in Marked

To use this tick the box, put in your fully qualified path to pandoc and add your arguments and bob is your proverbial uncle. The quickest way to find out where pandoc is installed on your Mac is to type the following from the terminal.

which pandoc

@dave_tucker

Increase the Awesome

I’m sitting at my desk right now (9pm Sydney time), waiting for my 3am change window that I need to be onsite at the data centre for. Now I am supposed to be working on a presentation I am giving on Friday entitled “Automation, Orchestration, and SDN”. I’ve been given about 20 minutes to cover these topics, so I’m spending quite a bit of time trying to get the right mix of content without geeking out too far for the intended audience (C-levels, project managers and lead engineers).

While trying to get the mix just right, my mind keeps going back to a comment I made last week on the “APAC Virtualization Roundtable” podcast (Episode 74 “SDN & Virtualisation from a Network Engineers perspective”)…

“Increase the awesome, remove the mundane!”

While initially sounding facetious, this comment is kind of where my brain has been going of late when trying to work out where I should focus my energies. While I’m thinking of ways to apply this idea to many aspects of my life, I would like to present them in the context of the presentation I am about to give (and the same context to which Continue reading

DCCP – Datagram Congestion Control Protocol

How does the internet work - We know what is networking

DCCP transport layer protocol is used to control the datagram congestion. It provides an excellent procedure to stop the internet fall down, if it is caused by the congestion. In fact, this protocol is a brilliant competitor to be used as a substitute of UDP protocol. DCCP account DCCP congestion control trait by means of a reliable acknowledgments delivery (in form […]

DCCP – Datagram Congestion Control Protocol

Agile Writing – Week 1 – Getting Started with JIRA, GreenHopper and Markdown

I finished reading The Phoenix Project at the beginning of May and it has had a profound affect on my outlook towards work. Not only was this a great read, but while I was reading I kept getting ideas on how I could implement the three ways at work. This diary documents the transition to an Agile Writing workflow.

Why bother?

Before I start covering the how, I thought I would spend a little time on the why. Agile is something that is usually associated with Software Development and you might be thinking "What has this got to do with writing?". I write technical documentation for a living, but I've been a long time have-a-go programmer and I recently had the pleasure of working on a professional software project. One of the things that amazed me was how Agile mad them so much more efficient.

  • Scope creep was eliminated through issue and requirements management
  • Many application releases gets product in the customer's hands sooner
  • Team maintains a constant velocity and is always striving to be more efficient
  • Everything that can be automated, is.

It is actually quite easy to draw parallels between application development and writing technical documentation. A Continue reading

Consider an International Relocation

Over three years ago I saw an opportunity to take an assignment to my company HQ in Seattle. After debating this for some time with my wife we took the plunge and moved to the US. The question is, “was it worth it?”. For me the answer is an overwhelming ‘yes’.  I’m moving back to […]

Author information

John Harrington

John is an experienced data center engineer with a background in mobile telecoms. He works as a network test engineer for a large cloud service provider, and is gradually accepting that he's a nerd. He blogs about network technology and careers at theNetworkSherpa.com. You can reach him on twitter at: @networksherpa

The post Consider an International Relocation appeared first on Packet Pushers Podcast and was written by John Harrington.

Route Distinguishers and Route Targets

People new to MPLS VPN are often unclear on what functions route distinguishers and route targets serve, and the difference between the two. Let's see if we can clear up some of that confusion. If you could use a refresher on VRF fundamentals, I encourage you to first check out my earlier articles on the topic, Intro to VRF lite and Inter-VRF Routing with VRF Lite.

Route Distinguisher

As you know, VRFs allow IP address space to be reused among isolated routing domains. For example, assume you have to connect to three customer sites, all of which are using 192.168.0.0/24 as their local network. We can assign each customer its own VRF so that the overlapping networks are kept isolated from one another in their respective routing domains.

This works well, but we need a way to keep track of which 192.168.0.0/24 route belongs to which customer. This is where route distinguishers come in. As its name implies, a route distinguisher (RD) distinguishes one set of routes (one VRF) from another. It is a unique number prepended to each route within a VRF to identify it as belonging to that particular VRF or customer. Continue reading

Angry SDN hipsters.

Some folks seem to get a little too hung up on one philosophy or another -- too blind to see good in any other form except the notions that have evolved in their mind.  I'm hoping I'm not one of them.  I do have opinions, but which I believe are rational.

The counter culture of networking waves the SDN banner.  That acronym seems to belong to them.  They don't know what it stands for yet, but one thing they seem to be sure of is that nothing good can come by allowing networking innovations to evolve or even to exist in their birthplace.

The way I see evolving the network fabric is through improving on the best of the past.  Every profession I know from medicine, finance, law, mathematics, physics, you name it -- all of them are building their tomorrow on a mountain of past knowledge and experience.  So I'm sure my feeling the same about the network doesn't make me outdated, just maybe not a fashionable SDN hipster.




Some angry SDN hipsters say that the core network needs to be dumbed down.  They must have had a "bad childhood," technically speaking.  One too many Cisco 6500's stuffed with Continue reading