BrassTacks
Brass Tacks, recovered.
Brass Tacks was my blog on Typepad from 2010 to 2022. Typepad is gone, so these posts were recovered from the Internet Archive and are republished as they were originally posted: same text, same images, same comments, original dates.
2022
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Let’s play in an AWS based SANdbox – Part 2 Setting up your AWS VPC and networks
In my previous post, I introduced the SANdbox Github repo and described the work that had been done to create an Virtual Lab that is capable of supporting NVMe/TCP traffic. In this post I’ll walk you through the steps to create your own SANdbox VPC in AWS that will eventually...
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Let’s play in an AWS based NVMe/TCP SANdbox!
One of the great things about NVMe/TCP is its flexibility. Not only can you use the NVMe/TCP protocol to connect hosts to storage systems over an arbitrary IP network topology; as originally described here, you can also run it in a surprising number of operating environments, including: traditional enterprise environments...
2020
2019
2017
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NVMe over Fabrics’ Discovery problem
TL;DR – Today, Fibre Channel provides an NVMe over Fabrics Discovery mechanism, Ethernet does not. This blog post describes an investigation that was performed to determine if an enhancement to the NVMe over Fabrics Discovery protocol was needed in order for it to support a Network Centric connectivity model as...
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The power of Layers
Originally posted by Erik Smith to Brasstacksblog Background I have a thing for breaking down complex topics into “Layers” (e.g., Storage Protocol Stacks). I use this approach because it breaks down what would otherwise be an overwhelming amount of information, into chunks of functionality that I can keep in my...
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ZTIP – Part 3: Provision and Transport
This is part 3 of a multi-part series that describes a “side-project” a small team of us (Jean Pierre (JP), Alan Rajapa and Massarrah Tannous and I) have been working on for the past couple of years. In part 1, I introduced an early version of this concept referred to...
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Zero Touch Infrastructure Provisioning (ZTIP)
This is part 2 of a multi-part series that describes a “side-project” a small team of us (Jean Pierre (JP), Alan Rajapa and Massarrah Tannous and I) have been working on for the past couple of years. You’ll note that in part 1 of the series, I was referring to...
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The IaaS Missing Link
The beginning Almost exactly two years ago, a small group of us (including Alan Rajapa and Massarrah Tannous) participated in a “Hack Attack” that was being run by one of the Storage Platform teams within EMC. Our concept was simple; we were going to completely eliminate the manual storage provisioning...
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How to determine a switch's role in a Clos network with MLAG’d leaves
A group of us have been experimenting with IP Fabrics recently and I'm curious to know if anyone has used the following approach or knows of work that accomplishes the same goal in a different way. When initializing an IP Fabric, one of the first decisions that needs to be...
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Storage Protocol Stacks for NVMe
With all of the attention that NVMe has been getting recently, I wanted to provide an NVMe specific version of the original Storage Protocol Stacks diagram. Thanks for reading!
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NVMe over Fabrics: Not ready (yet)
Image credit: https://www.someecards.com/usercards/viewcard/MjAxMy03ZWMxZjIxZmRkMjRmZGNl/ If you’re into IT infrastructure and you aren’t yet familiar with NVMe and its potential benefits, now would probably be a good time to start reading. In fact, since there’s already so much high quality material that describes what NVMe is, why it’s useful and how it...
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Slow Drain due to Bandwidth mismatch and Large Block READs
Every once in a while, you come across information that makes you understand something in a completely new way. Image credit: https://farscapedevelopment.wordpress.com/2012/07/06/eureka/ I had just such an experience a few weeks back, and Alan Rajapa and I have been working in the lab since then to try and come to...
2016
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Thanks EMC!
Just about 19 years ago, I pulled into the yard at Tresca Brothers and asked my dispatcher if I should wash out for the day. He said “No. One more up front” meaning I had another load to deliver and that I should get it from the Central mix (basically...
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Storage protocol stacks
The following diagram was put together for my EMC World 2016 presentation. It provides a graphical overview of the most commonly used Storage Protocols and how they relate to one another. A special thanks to David Black and Tony Rodriguez for their inputs! Thanks for Reading!
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Slow Drains are impacting your SAN!
If you work with Fibre Channel on a regular basis and have come to depend on its excellent performance attributes, you might be surprised to learn that many of the cases handled by our SAN team in Customer Support are related to performance problems. Typically, as we dig into these...
2015
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Fibre Channel is better than Ethernet...
…for Enterprise Storage. Although this blog post isn’t an April fool’s joke, I do greatly appreciate them when they are done well. As a result I’m slightly in awe of the amount of thought Tony Bourke has put into his last three (2013, 2014 and 2015). Truth be told, I'm...
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Join me at EMC World 2015!
It's almost time for EMC World (May 4th - 7th) and I’m happy to say that once again I’ve been honored with a couple of highly coveted EMC World speaking slots! Based on the very positive feedback I received from last year, I’ll be sticking to a similar format and...
2014
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A Simple Virtual Storage Network Demo
I'm still working on the fourth installment of the Virtual Storage Network (VSN) blog post series, but I wanted to share this link to a youtube video that shows a very simple (2 port) VSN demo that we'll be showing next week at EMC World. The topology that I'm using...
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Virtual Storage Networks – Part 3 (Multi-tenant capable topologies)
This is part three of a blog series that describes a new concept we're referring to as a Virtual Storage Network. In part 1 of this series, I introduced the Virtual Storage Network or VSN as concept that enables the dynamic creation of storage service compositions. I also provided some...
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New E-Lab Interoperability Navigator features
As I mentioned in a previous post, the E-Lab Navigator Team recently finished a complete redesign of their user interface. If you’re interested in much more detail, check out the introduction video and the user guide. Rather than repeat what they’ve provided in the guide and video, I'd like to...
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An Introduction to Virtual Storage Networks
I recently started a VSN blog series that describes (in great detail) a new concept that we’re referring to as a Virtual Storage Network or VSN. As I was writing the third installment in the series, I realized the approach I was using to define the VSN concept was analogous...
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Fast Sideways - A connectivity point of view
Although I mentioned this functionality in a previous blog post, the impact that this type of use case will have on connectivity automation is so significant that it deserves to have it's own post. The first time I heard the FAST Sideways concept mentioned publicly was by Brian Gallagher during...
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Join me at EMC World 2014!
It's almost time for EMC World again (May 5th - 8th) and I'm happy to say that I've been granted the privilege of presenting to our Customers again. I'm actually very excited about this year because we're introducing a few new concepts, demonstrating at least one of them and mixing...
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Virtual Storage Networks – Part 2 (Requirements for multi-tenant storage)
In part 1 of this series, I introduced the concept of a Virtual Storage Network, provided some background information and stated what we believe the requirements for multi-tenant storage are. In this post I’ll dig into the details of those requirements. Requirements for multi-tenant storage As stated before, the following...
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Coming soon: The next generation E-Lab Interoperability Navigator!
As many of you know, E-Lab Interoperability Navigator (ELN) is a free E-Lab resource that anyone can use to determine which configurations and solutions have been tested and are currently supported by EMC. What many of you may not fully appreciate is the staggering amount of work that it takes...
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Virtual Storage Networks - Part 1
We’ve been busy. For the past three years a group of people including Mark Lippitt, Vinh Dinh, Doug Fierro and I have been working on an idea that we’re referring to as a Virtual Storage Network or VSN for short. The VSN concept seeks to take advantage of the major...
2013
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FCoE Case Studies TechBook update
An updated version of the FCoE Case Studies TechBook (v3.0) has been posted to powerlink and emc.com New in this version is a chapter titled “Brocade VDX Switches Setup Examples” that was written by Aditya Nadkarni. It provides an overview of the VDX switch/VCS Fabric, a description of supported topologies...
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Join me at EMC World 2013!
If you’re planning to attend EMC World 2013 May 6th-9th at the Venetian, Las Vegas, and you’re interested in FC, FCoE, iSCSI or Network Virtualization, please consider attending at least one of the following sessions: Storage Area Networking: SAN Technology Update & Best Practice Deep Dive for FC, FCoE, &...
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Target Driven Zoning works!
Thanks to EMC’s DJ Brown and some help from Blayne Rawsky at Brocade, we finally have TDZ running in the lab. The first peer zone was successfully registered on 3:55 PM EDT on Thursday April 4th 2013. Test configuration The test configuration was deliberately kept small and is shown below....
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Yet another reason why enabling FIP Snooping is important when using FCoE
As I’ve mentioned in a couple of previous posts (see here and here), I believe that FIP Snooping is a requirement when you’re using FCoE. Recently, a friend from Juniper (Simon Gordon) shared a bit of information with me that supports this position and I found it interesting enough to...
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A new EMC FCoE “Case Studies” TechBook revision is available!
A new version of the “Fibre Channel over Ethernet (FCoE) and Data Center Bridging (DCB) Case Studies” TechBook is available. This version introduces a new Juniper QFX3500 case study as well as a few updates (bug fixes) to the existing case studies. The complete list of configurations described in the...
2012
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VN2VN – The Good, the Bad and the Ugly
About 19 months ago I wrote a post that described two new FCoE protocols (PT2PT and VN2VN) being worked on by the T11 working group “FC-BB-6”. In that post I also promised to provide two additional posts describing how these protocol work and this post is intended to fulfill the...
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A problem with I/O Consolidation… and Network Virtualization?
Some number of weeks ago I helped troubleshoot an FCoE problem involving a flaky twinax cable that was causing excessive bit errors. The symptom being observed was very strange at first glance; CRC errors were being logged on interfaces that should have been idle. At first we thought the switch...
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Network Virtualization – Networking’s 21st century equivalent to the space race
This post was written with Patrick Mullaney. Overview Similar to the milestones in the space race timeline, I believe that Monday July 23rd (the day VMware announced plans to acquire Nicira) will be viewed by networking enthusiasts as a significant milestone in the evolution of our discipline. Just to keep...
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Join me at EMC World 2012!
If you’re planning to attend EMC World 2012May 21-24, The Venetian, Las Vegas, and you’re interested in FC, FCoE, iSCSI or Network Virtualization, please consider attending at least one of the following sessions: FC/FCoE – Topologies, Protocols and Limitations Days and times: Tuesday 10:00a and Wed 4:15p Presenter: Erik Smith...
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New FCoE TechBooks are available!
Over the past couple of months we’ve been working on adding some FCoE specific “Blade Server” information to the FCoE TechBook. Actually the vast majority of the work was done by two of my colleagues, Aditya Nadkarni and Shreedhan Nikam (more about them later). Early on in this process of...
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First you must enable RAID, before you can disable it.
Before you jump into this post thinking a "storage guy" is in any way recommending that you disable RAID on your array, please understand that I’m talking about disabling "SW RAID" on a server ONLY! I’m writing this as penance for spending far too much time on this problem. To...
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A thought experiment - The Universal Fabric
This post is in response to a post by Scott Lowe, another post by Maish Saidel-Keesing and his reaction to TDZ as a potential solution to satisfy his requirements for a “dvFabric”. Maish’s statement via twitter: “…but this (TDZ) only covers block storage. What about NAS?” honestly set me back...
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Does FCoE require DCB Ethernet?
I received a question earlier today that asked the following: "I have heard some folks argue that ETS (Enhanced Transmission Selection) is NOT required to make FCoE work. I'm thinking specifically of the case in which a CNA is connected to a DCB-capable Ethernet switch that is doing FIP Snooping,...
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FC and FCoE versus iSCSI – “Network-centric” versus “End-Node-centric” provisioning
Which is easier to use: FC, FCoE, or iSCSI? This is the question we wanted to answer as we set out few months ago to test a series of nine configurations in the lab. Our approach was to determine the number of provisioning steps required when using each protocol to...
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Partner Mac Address: 00:00:00:00:00:00
While setting up bonding on a Linux host running SLES 11, a colleague and I noticed that the output from cat /proc/net/bonding/bond0 showed a “Partner Mac Address:” of 00:00:00:00:00:00. (BTW, we’ve also observed this symptom on at least one other distro (Debian)). We were interested in the Partner MAC Address...
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Introducing Target Driven Zoning (TDZ)
At 9:28 on Tuesday 12/6/2011, the T11 FC-GS-7 working group approved a motion to incorporate the text for “Peer Zoning” that was prepared by Claudio DeSanti (Cisco). The actual text can be found in the T11 document 11-411v2. To me this moment marked the culmination of a four year journey...
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Hard zoning versus soft zoning in a FC/FCoE SAN
Over the past few weeks, I’ve answered a bunch of questions that have asked something along the lines of “Should I use Hard Zoning or Soft Zoning?” And no, I have no idea why these questions are coming up now… The short answer If you’re familiar with FC Zoning as...
2011
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FCoE TechBook update for November 2011
An updated version of the FCoE TechBook (v11.0) has been posted to powerlink and emc.com. New for this version is a case study that describes how to configure FCoE on the Nexus 7000 and MDS. The topology that is configured within the case study is shown below. Also Shreedhan Nikam...
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Upcoming EMC / Cisco webcast "Designing High Availability into a Converged Networking Environment"
Please join J Metz of Cisco and I (Erik Smith of EMC) for a webcast that will cover some of the HA considerations that you need to think about before moving to a Converged Nework topology. The webcast details are provided below. Please remember to pre-register. Date: November 10, 2011...
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A Multi-Hop FCoE topology example
As I mentioned in the previous post, in early November we will be releasing an updated version of the FCoE TechBook that will contain a number of fixes as well as a new Multi-Hop case study. The exact topology that will be configured in that case study is shown below....
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FC/FCoE Connectivity options as of 11/3/2011
Well…we’ve been talking about it since EMC World in May and on November 3rd EMC will officially release support for a Director Class Multi-Hop FCoE solution! More specifically, we will be adding the Cisco Nexus 7000 and FCoE support for the Cisco MDS 95xx to the November EMC Support Matrix...
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FCoE TechBook update for October 2011
An updated version of the FCoE TechBook (v10.0) has been posted to powerlink and emc.com. New in this version is a chapter titled “EMC Storage in an FCoE Environment” that was written by Shreedhan Nikam. It contains information for VMAX as well as VNX and is a very welcome (and...
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Interoperability issue between Brocade CNA and Cisco Nexus 5596
The other day one of my colleagues, Mugdha Kulkarni, brought an interoperability issue to my attention involving a Brocade 1010 / 1020 CNA (Windows Server 2008, Driver 2.3.0.2) and a Cisco Nexus 5596 (NX-OS 5.0(3)N1(1c)). The problem was the Brocade CNA was unable to login to the Nexus 5596. Complicating...
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Twinax support table (6/28/2011)
The twinax support table has been updated to include Broadcom CNAs and VNX. Please use the following version as of (6/28/2011). This information will also be added to the July version of the EMC FCoE Tech Book The model numbers for the EMC twinax cable are included below. Thanks for...
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FC/FCoE Connectivity options as of 6/27/2011
About a month ago I received an email from someone asking "When will the FCoE Tech Book be updated to properly reflect EMCs support for native FCoE on our arrays?" My initial reaction was "OH!, <golly-gee>" and then the inevitable"Of all the <interesting> pieces of information to <absentmindedly> leave out"....
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Enabling FIP Keep Alive on Brocade 8000
I received a question from a colleague in Singapore yesterday asking about the D bit in FIP FKA_ADV_Period Descriptor. Apparently, a customer was wondering if it could be changed from “one” to "zero" on a Brocade 8000 switch. A portion of the customer's email is shown below: The Discovery Advertisement...
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Eliminating the SAN “Air-gap” requirement with FCoE and vPC
While reading J Metz’s blog post, I noticed a comment from one of my friends at Brocade that made reference to an “Air-gap fabric” requirement and this prompted me to provide a response of my own. In my response, I briefly outlined not only what I’ll be writing about in...
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Connectivity changes for April 2011
The updates for the month of April (Yes, I know it’s May!) are listed below: Brocade Firmware added to the April ESM (Courtesy of Aditya Nadkarni) FOS v6.4.1_dcb was added for the Dell M8428-k convergence I/O module FOS v6.3.2b is tagged as the new "Target" release Cisco UCS Firmware added...
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FCoE Multihop and VE_Ports
In the April EMC Support Matrix, EMC will be posting support for NX-OS 5.0(2)N2(1) for the Nexus 5010, 5020 and 5548. In addition, we will also now support the creation of Virtual E_Ports (VE_Ports) on these products. This post discusses what VE_Ports are, the protocol used to instantiate them and...
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Connectivity changes for March 2011
The updates for the month of March are listed below: Brocade Firmware added to the March ESM to support the FCoE 10-24 blade in DCX (Courtesy of Erik Paine and Aditya Nadkarni) FOS 6.4.1_FCoE – This version adds support for non-disruptive CP failover and is capable of supporting connections from...
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Conversation topics for EMC World 2011
Since I end up spending much of my time in the lab, you probably won’t be surprised to learn that I consider EMC World to be one of the high points of the work year…Setting aside the much-needed (and appreciated) opportunity for social interaction, I find it extremely helpful to...
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PT2PT and VN2VN - Directly connecting an FCoE initiator to an FCoE target (Part 1 – Overview)
Recently, I received a few questions asking “how do you connect an FCoE initiator directly to an FCoE target without using an FCF?” The short answer is, “with the FC-BB-5 version of FCoE you can’t!” The reason is, this functionality was intentionally deferred to FC-BB-6. To help clarify what is,...
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New EMC TechBooks are available!
For the past several years, many of my colleagues and I have been updating and adding to the EMC Networked Storage Topology Guide. While all of this work has made it a great technical resource (IMHO), it has also grown the topology guide into a 2500 page, 60 MB .pdf...
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Connectivity changes for February 2011
Well, it’s been a very busy month! Although I personally don’t have much to show for it in terms of connectivity updates, as you can see below, my colleagues have been busy!! In case you’re wondering, I’m currently working with VE_Ports on Cisco Nexus 5k as well as a comparison...
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FCoE login failure when connecting to Nexus 5548
A couple of months ago while we were installing our Nexus 5548s in the E-Lab, we noticed an FCoE login problem. Although we configured the 5548s in exactly the same manner described for the Nexus 5020 / 5010 in the FCoE TechBook, the FCoE ENodes would not log in. At...
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Connectivity changes for January 2011
The updates for the month of January are listed below: Brocade (Courtesy of Aditya Nadkarni) Firmware added to the January ESM EOS 9.09.09 FOS v6.3.2b FOS v6.4.1 FOS v6.3.2a (tagged as the target release for FOS) Note: Target Releases are a new concept for the January ESM and according to...
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Twinax support table
In my last post, I provided information that described which twinax cables were supported in a number of different configurations. Recently, Mark Lippitt and I debated the best way to present this information in the February edition of the FCoE TechBook, and decided that creating a table made the most...
2010
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Should I use optical fiber or twinax cable?
Earlier this week I received a question regarding EMC’s recommendations for using twinax cable. My response is included below, but I need to tip my hat to Mark Lippitt for reviewing, correcting, and adding a couple of different considerations that I overlooked. One other point worth mentioning is that we...
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Creating SAN Port Channels when using NPV mode on Nexus 5k
I received a question recently from Anthony Padula that asked if SAN Port Channels were supported on a Nexus 5000 running in NPV mode. After speaking with a few colleagues, locating the documentation, and setting it up in the lab, I am happy to say that the answer is yes!...
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Connectivity Changes for December 2010
The connectivity related changes for the month of December are as follows: FCoE tech book vPC overview and vPC case studies added EMC RecoverPoint solution overview added EMC Celerra Multi-Path File System (MPFS) solution overview added HP Blade Server (Courtesy of Aditya Nadkarni and Shreedhan Nikam) Hardware and firmware added...
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FIP, FIP Snooping Bridges, and FCFs (Part 2 – FIP Snooping Bridges and Fibre Channel Forwarders)
In my last post I described what FIP is, how FIP bridges the gap between the expectations of the Fibre Channel protocol and the reality of an Ethernet network, and described how FIP works. In this post, I’ll expand on this subject and describe why FCoE requires ENodes to be...
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Connectivity Changes for November 2010
In my first Connectivity Changes post, I committed to providing monthly updates. Looking back, I should have included a “no changes clause”. Something to the effect of, "if there are no connectivity changes for the month, I won't be providing an update". Having neglected to include the aforementioned “no changes...
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FIP, FIP Snooping Bridges, and FCFs (Part 1 – “FIP”, the FCoE Initialization Protocol)
Background: I had an interesting conversation the other day with a colleague in another engineering group at EMC. He was in the process of getting ready to order a 10 GbE switch to support some NAS testing. He also mentioned that he would eventually like to test FCoE. Although I...
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Nexus 5000 / 2232PP configuration
As I’ve mentioned in my previous posts, I work for the Connectivity team in EMC’s E-Lab. Our primary responsibility is to set up configurations that our customers are likely to use, enable many of the more useful features and then see what kind of trouble we can cause by performing...
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Connectivity Changes for October
In my previous post I wrote about documentation and how it can make your life miserable when it’s missing, or worse, inadequate. Oddly enough, the opposite is also true! Having too much documentation, especially when you are looking for a specific piece of information, can also make your life miserable…...
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Getting down to Brass Tacks (well almost…)
OK, I’ve finally decided to take the plunge and start a blog on Storage Area Networks. Why now? Well…thanks to things like FCoE, there’s a lot going on and a ton of new things to learn. I figure as I’m learning and figuring out what makes sense in our lab,...