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Storage Distance by Protocol, Part IV: Fibre Channel over Ethernet (FCoE)

In the past articles we’ve talked about doing distance extension for SANs, focusing first on building the physical elements that are required, before moving on to how Fibre Channel can be extended using buffer credits.

In this article we’re going to talk about how it is best to think of extending Fibre Channel over Ethernet (FCoE) SANs (finally!).

I know, I know, I start off this whole shebang by saying I’m going to talk about FCoE and distance, and it takes me this long to get to it? Sheesh! Read More »

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Storage Distance by Protocol, Part III – Fibre Channel

In the previous article we looked at some of the physical characteristics of building a SAN extension. In other words, we looked at the different ways there are to “build the pipe.” We didn’t, however, get the chance to talk about the speed or capacity of the pipes, nor did we talk about the various methods to fill the pipe with SAN data.

In this article, we’re going to look at the first of four specific methods of how we can extend SANs across distances using those pipes: “Native” Fibre Channel (FC). Understanding how FC works becomes critical for understanding how distance solutions are resolved using the technology, and that in turn leads us to understand how something like Fibre Channel over Ethernet (FCoE) differs.

Afterwards, we’ll take a brief look at how the pieces fit together and are part of the process for building a strong solution. Read More »

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Storage Distance by Protocol, Part II – Physical Layer

In the last article, we looked at the big picture of what is involved in creating a SAN distance extension. In this article, we’re going to take a slightly closer look at the physical requirements and with luck we’ll be able to clear up some general confusion and misconceptions along the way.

Puzzle Pieces 2There is a lot of information about these different elements available via a quick search on your favorite search engine. What I find, though, is that there is usually very little context that accompanies the descriptions or, at best, the authors assume that you may have more of an understanding about some of these technologies than you do. In this case, if I’m going to err it will likely be on the side of making it too accessible and in Plain English, which is something I can live with.

As usual, this is a mid-level view. There are many deep dives that will go into each subject in fine-toothed detail available on the web, but we’re going to stay focused on what you need to know for extending SANs across distances.

Again, this is a rather long post, but hopefully it will be useful as a reference point for you. Read More »

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Storage Distance by Protocol – FC, FCoE, and FCIP, Part I

A long time ago I got asked to write about how to use Fibre Channel over Ethernet (FCoE) for distance. After all, we were getting the same question over and over:

What is the distance limitation for FCoE?

Now, the short answer for this can be checking out various data sheets for the Nexus 2000, Nexus 5500, Nexus 6000, Nexus 7000, or MDS 9X00 product lines. But it didn’t answer the most obvious follow-up questions: “Why?” and “How?”

Problem is, whenever you start talking about extending your storage connectivity over distance, there are many things to consider, including some things that many storage administrators (or architects) may not always remember to think about. The more I thought about this (and the longer it took to write down the answers), the more I realized that there needed to be a good explanation for how this worked.

Red_Propeller_Cap_clothing_icon_ID_407Generally speaking, the propeller spins the ‘other way’ when it comes to storage distance.

To that end, I began writing down the things that affect the choice for selecting a distance solution, which involves more than just a storage protocol. And so the story grew. And grew. And then grew some more. And if you’ve ever read any blogs I’ve written on the Cisco site you’ll know I’m not known for my brevity to begin with! So, bookmark this article as a reference instead of general “light reading,” and with luck things will be clearer than when we started. Read More »

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#EngineersUnplugged S3|Ep3: FCOE, Fact or Fiction (Part 1)

Welcome to another episode of Engineers Unplugged! This week features Cisco’s Andrew Levin (@AndLevin) discussing the use cases for FCOE with Nexus IS’s Paul Sferratore (@MadItalianATL). This is a detailed and nuanced debate of the pros and cons based on a variety of scenarios from large-scale to smaller deployments.

Listen in and let us know what you think about efficiency and cost savings:

Andrew Levin and Paul Sferratore show off their unicorns. Do not try this at home.

Andrew Levin and Paul Sferratore show off their unicorns. Do not try this at home.

Welcome to Engineers Unplugged, where technologists talk to each other the way they know best, with a whiteboard. The rules are simple:

  1. Episodes will publish weekly (or as close to it as we can manage)
  2. Subscribe to the podcast here:
  3. Follow the #engineersunplugged conversation on Twitter
  4. Submit ideas for episodes or volunteer to appear by Tweeting to @CommsNinja
  5. Practice drawing unicorns

Join us next week for Part 2 of this discussion. Meanwhile, for all the updates and behind the scenes, like Engineers Unplugged on Facebook!

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