Change your vocabulary, change your career

When people look at their careers, the focus pretty naturally falls to skills acquisition. Almost everyone believes that their future hinges on learning some skill or mastering some talent. Maybe you want to know more about business or strategy. Perhaps you think you need to read leadership books or find Harvard Business Review articles on […]

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The post Change your vocabulary, change your career appeared first on Packet Pushers Podcast and was written by Michael Bushong.

Invest in great tools for your engineers

Can you remember your last newly hired engineer, all shiny and happy and new? Can you also remember the look on their face when they received their corporate craptop? Or maybe they received a decent laptop, but it came in a ten dollar laptop bag. The tech industry spends a lot of time and effort […]

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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 Invest in great tools for your engineers appeared first on Packet Pushers Podcast and was written by John Harrington.

Don’t Alienate Your Co-Workers With Your Passion

We geeks love our tech. Really love it. I mean…really, really get down deep into a technology, decide it’s the best thing ever, and then wave the flag around high. Make the wallpaper. Wear the t-shirt. Evangelize the ignorant. Shout down the naysayers. Mock the competitors. Fan the flames of rivalry. Linux vs. Microsoft. Mac […]

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Ethan Banks

Ethan Banks, CCIE #20655, has been managing networks for higher ed, government, financials and high tech since 1995. Ethan co-hosts the Packet Pushers Podcast, which has seen over 3M downloads and reaches over 10K listeners. With whatever time is left, Ethan writes for fun & profit, studies for certifications, and enjoys science fiction. @ecbanks

The post Don’t Alienate Your Co-Workers With Your Passion appeared first on Packet Pushers Podcast and was written by Ethan Banks.

CDN activity and what it means for network monitoring

One of the more useful ways to find out what is happening in the real world of network monitoring and troubleshooting is to have a look through some of the many on line forums that exist. Spiceworks Community and SolarWinds Thwack are examples but there are many more. Here you can spot trends as to […]

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Darragh Delaney

Technical Director at NetFort

Darragh Delaney is head of technical services at NetFort. As Director of Technical Services and Customer Support, he interacts on a daily basis with NetFort customers and is responsible for the delivery of a high quality technical and customer support service.

Darragh has extensive experience in the IT industry, having previously worked for O2 and Tyco. His User and Network Forensics blog. for Computer World focuses his experiences of network management and IT security in the real world. In his current role Darragh is regularly on site with network administrators and managers and this blog is a window into the real world of keeping networks running and data assets secure.

He shares network security and management best practices on the NetFort blog. Follow Darragh on Twitter @darraghdelaney and NetFort Technologies @netfort. You can also contact him Continue reading

eFSU on VSS (WS-6513, Sup2T)


I performed an eFSU (enhanced Fast Software Upgrade) of a pair of Cisco WS-6513-E switches in VSS. eFSU is the closest one can get to a true ISSU (in service software upgrade) of a VSS chassis. The entire process took 25 minutes. It is slower than a conventional FSU that involves changing the boot variables on the switch to point to the new software image file and then reloading the switches. This will cause a complete outage irrespective of whether devices are single or dual attached to the VSS. With the eFSU, we lost a single ping in the complete process from a workstation that was connected to an upstream 4500 switch that was dual homed to the VSS chassis. However, for devices that were single attached, there was a considerable outage (60-180 seconds).

I'll go over the process and hopefully this post should familiarize other network engineers who want to attempt an eFSU but haven't done it before. I've capture screenshots of the upgrade process, so we can look at some of the interesting logs on the switches.

Current IOS: 15.1(1)SY
New IOS: 15.1(1)SY1

Cisco's documentation is very precise and straight forward and can be found here.

Visibility, Debugging and Network Virtualization (Part 1)

[This post was written by Martin Casado and Amar Padmanahban, with helpful input from Scott Lowe, Bruce Davie, and T. Sridhar]

This is the first in a multi-part discussion on visibility and debugging in networks that provide network virtualization, and specifically in the case where virtualization is implemented using edge overlays.

In this post, we’re primarily going to cover some background, including current challenges to visibility and debugging in virtual data centers, and how the abstractions provided by virtual networking provide a foundation for addressing them.

The macro point is that much of the difficulty in visibility and troubleshooting in today’s environments is due to the lack of consistent abstractions that both provide an aggregate view of distributed state and hide unnecessary complexity. And that network virtualization not only provides virtual abstractions that can be used to directly address many of the most pressing issues, but also provides a global view that can greatly aid in troubleshooting and debugging the physical network as well.

A Messy State of Affairs

While it’s common to blame server virtualization for complicating network visibility and troubleshooting, this isn’t entirely accurate. It is quite possible to build a static virtual datacenter and, assuming the vSwitch Continue reading

The Value of Certifications

I hope to clear the air on what a vendor certificate (or any certificate, such as a degree/diploma/etc) is, and is not. Too many times have I heard/seen people place too little or too much stock in the single piece of paper. What a certificate is A certificate, simply put, is proof that on a […]

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Ken Matlock

Ken Matlock

Ken Matlock is a networking veteran of 19 years. He has worked in many fields in the networking industry including Service Provider, Retail, and Healthcare. When he's not fixing the problems of the networking world, he can be found studying for his CCIE, spending time with his family, and trying to chase the ever-elusive sleep.

He can be found on twitter @KenMatlock , email at [email protected] , irc.freenode.net #PacketPushers, or the occasional blog or forum post.

The post The Value of Certifications appeared first on Packet Pushers Podcast and was written by Ken Matlock.

Cisco onePK: Now I Get It

I had an opportunity recently to sit in a Cisco onePK lab and it opened my eyes to exactly what Cisco is doing with onePK, why it’s going to be so important as Software Defined Networking (SDN) continues to gain traction, and why onePK is different than what anyone else is doing in the industry.

onePK is a key element within Cisco’s announced Open Network Environment SDN strategy. onePK is an easy-to-use toolkit for development, automation, rapid service creation and more. It enables you to access the valuable data inside your network via easy-to-use APIs.

Source: www.cisco.com/go/onepk

Since having my own eyes opened, I’ve been pondering how to explain my new found understanding in a way that others will grasp. In particular to business decision makers (BDMs) and technical decision makers (TDMs). I’m really, really, struggling to come up with a good analogy for BDMs. I’m still working on that one. Surprisingly, I’m also struggling to come up with a sound analogy that will work with the majority of TDMs that I know. Maybe I shouldn’t be so surprised at that since all the TDMs I deal with are on the infrastructure side of things (networks, storage, Continue reading

Show 153 – Cisco Live 2013 Roundtable Discussion with Tech Field Day

At Cisco Live US 2013, we were able to get together a nice group of folks to share their opinions on the announcements we found most interesting. You’ll know some of them from Tech Field Day, an event Greg and I have been a part of several times. This show is good conversation with smart […]

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Ethan Banks

Ethan Banks, CCIE #20655, has been managing networks for higher ed, government, financials and high tech since 1995. Ethan co-hosts the Packet Pushers Podcast, which has seen over 3M downloads and reaches over 10K listeners. With whatever time is left, Ethan writes for fun & profit, studies for certifications, and enjoys science fiction. @ecbanks

The post Show 153 – Cisco Live 2013 Roundtable Discussion with Tech Field Day appeared first on Packet Pushers Podcast and was written by Ethan Banks.

Cisco onePK: Now I Get It

I had an opportunity recently to sit in a Cisco onePK lab and it opened my eyes to exactly what Cisco is doing with onePK, why it's going to be so important as Software Defined Networking (SDN) continues to gain traction, and why onePK is different than what anyone else is doing in the industry.

onePK is a key element within Cisco's announced Open Network Environment SDN strategy. onePK is an easy-to-use toolkit for development, automation, rapid service creation and more. It enables you to access the valuable data inside your network via easy-to-use APIs.

Source: www.cisco.com/go/onepk

Since having my own eyes opened, I've been pondering how to explain my new found understanding in a way that others will grasp. In particular to business decision makers (BDMs) and technical decision makers (TDMs). I'm really, really, struggling to come up with a good analogy for BDMs. I'm still working on that one. Surprisingly, I'm also struggling to come up with a sound analogy that will work with the majority of TDMs that I know. Maybe I shouldn't be so surprised at that since all the TDMs I deal with are on the infrastructure side of things (networks, storage, Continue reading

Your Career – Enemies Within and Without

In the mood for some self analysis and reflection around your career and your employer? Good. I’ve strong feelings about employment in general and even stronger ones around balancing it with your personal life (I wouldn’t dare say private any more) and making work work for you. I’m definitely in the work to live camp. […]

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Steven Iveson

Steven Iveson

Steven Iveson, the last of four children of the seventies, was born in London and has never been too far from a shooting, bombing or riot. He's now grateful to live in a small town in East Yorkshire in the north east of England with his wife Sam and their four children.

He's worked in the IT industry for over 15 years in a variety of roles, predominantly in data centre environments. Working with switches and routers pretty much from the start he now also has a thirst for application delivery, SDN, virtualisation and related products and technologies. He's published a number of F5 Networks related books and is a regular contributor at DevCentral.

The post Your Career – Enemies Within and Without appeared first on Packet Pushers Podcast and was written by Steven Iveson.

Heatsink Upgrade

A little detour from the networking topics today to show off a little weekend tech project. I recently ran into some overheating problems with my home BYO PC. Core Temp was showing upwards of 70 degrees Celsius during normal operation, and under load, it would sometimes just shut down completely. Here’s the setup I had as of 2 days ago: The rear fan, which takes air in, was not working due to a short.

Heatsink Upgrade

A little detour from the networking topics today to show off a little weekend tech project. I recently ran into some overheating problems with my home BYO PC. Core Temp was showing upwards of 70 degrees Celsius during normal operation, and under load, it would sometimes just shut down completely. Here’s the setup I had as of 2 days ago: The rear fan, which takes air in, was not working due to a short.

Network Security and the N00b Meter

This morning I read an article in which the writer thought that wireless security was too inconvenient and difficult, so he simply disabled it, leaving his network wide open. He was tired of his complex password being too hard for guests to use and made the comparison that they didn’t have to use these kinds […]

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Mrs. Y

Snarkitecht at Island of Misfit Toys

Mrs. Y is a recovering Unix engineer working in network security. Also the host of Healthy Paranoia and official nerd hunter. She likes long walks in hubsites, traveling to security conferences and spending time in the Bat Cave. Sincerely believes that every problem can be solved with a "for" loop. When not blogging or podcasting, can be found using up her 15 minutes in the Twittersphere or Google+ as @MrsYisWhy.

The post Network Security and the N00b Meter appeared first on Packet Pushers Podcast and was written by Mrs. Y.

Optimizing and Protecting Spanning Tree – Lab Testing

Unfortunately the equipment I was using didn’t support PVST+ (Sup2Ts in 6503 Catalyst Switches), so I skipped testing UplinkFast and BackboneFast as these are incorporated in 802.1w (RSTP) and 802.1s (MSTP, which is basically an extension of RSTP).

BPDU Guard

image

For this test, SwitchD will be treated as a Rogue Switch being attached to the network.  Initially, SwitchC’s port 2/1 is configured as an access port with only PortFast enabled.

  1. 1. Disconnect link between SwitchC and SwitchD
  2. 2. Configure SwitchC port 2/1 as an access port in VLAN 10 with PortFast enabled.
  3. 3. Configure SwitchD port 2/1 as an access port in VLAN 10. Configure the priority on VLAN 10 to be 0.
  4. 4. Reconnect link between SwitchC and SwitchD and check topology for VLAN 10. SwitchD should be the root for VLAN 10.
  5. 5. Disconnect link between SwitchC and SwitchD
  6. 6. Enable BPDU Guard on Switch C port 2/1
  7. 7. Reconnect link between SwitchC and SwitchD. SwitchC port 2/1 should move to an err-disable state. Verify with sh interfaces status err-disabled. Verify SwitchD is no longer the root for VLAN 10.

*Jul  5 22:02:06.023: %SPANTREE-2-BLOCK_BPDUGUARD: Received BPDU on port GigabitEthernet2/1 with BPDU Guard enabled. Disabling Continue reading

Masterclass – Tcpdump – Expressions

This Masterclass article series aims to provide in-depth technical information on the installation, usage and operation of the classic and supremely popular tcpdump network traffic analysis program including alternatives, running tcpdump as a process, building expressions, understanding output and more. I’ve covered the Basics and Parameters previously and here I move on to filter Expressions; […]

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Steven Iveson

Steven Iveson

Steven Iveson, the last of four children of the seventies, was born in London and has never been too far from a shooting, bombing or riot. He's now grateful to live in a small town in East Yorkshire in the north east of England with his wife Sam and their four children.

He's worked in the IT industry for over 15 years in a variety of roles, predominantly in data centre environments. Working with switches and routers pretty much from the start he now also has a thirst for application delivery, SDN, virtualisation and related products and technologies. He's published a number of F5 Networks related books and is a regular contributor at DevCentral.

The post Masterclass – Tcpdump – Expressions appeared first on Packet Pushers Podcast and was written by Steven Iveson.

Ambassadors Cookbook for Enterprise now available

At the beginning of 2013 I was asked to join the Juniper Ambassador team; essentially an outreach program to those active in social channels including the J-Net community.  Whilst I was appreciative of the vendor swag; it wasn’t until the community manager had the bright idea for us to collaborate on a book did it […]

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Glen Kemp

Professional Services Consultant at Fortinet, Inc

Professional Services Consultant. Designing & deploying “keep the bad guys out” technologies. Delivering elephants and not hunting unicorns.

Please free to add me on , follow me on Twitter or check out my other blogs on Fortinet Blog, sslboy.net and SearchNetworking.

The post Ambassadors Cookbook for Enterprise now available appeared first on Packet Pushers Podcast and was written by Glen Kemp.

KIClet: IOS “network” Command Cheating

I have always used the “network 0.0.0.0 0.0.0.0” statement to describe “all interfaces” when configuring a routing protocol like EIGRP. I know that it’s not correct, but I never stopped to wonder why my bad habit still worked. Then, I found this good article by @jdsilva explains this is IOS just assuming you had a “brain fart” and meant to type the proper “network 0.0.0.0 255.255.255.255” I’m studying for the CCIE and it can be really good to identify these bad habits that, while in real life may not be too bad, especially this kind, where the result is the same, but on exams can mean the difference between failure and success.

KIClet: IOS “network” Command Cheating

I have always used the “network 0.0.0.0 0.0.0.0” statement to describe “all interfaces” when configuring a routing protocol like EIGRP. I know that it’s not correct, but I never stopped to wonder why my bad habit still worked. Then, I found this good article by @jdsilva explains this is IOS just assuming you had a “brain fart” and meant to type the proper “network 0.0.0.0 255.255.255.255” I’m studying for the CCIE and it can be really good to identify these bad habits that, while in real life may not be too bad, especially this kind, where the result is the same, but on exams can mean the difference between failure and success.

You have a new manager – now what do you do?

We’ve all been there – a recent re-org or maybe your boss gets promoted or your boss leaves and you end up with a new manager. As I have mentored people over the years, I’d say that the most common reaction is “Crud! I have to start over.” But once you get past that moment […]

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The post You have a new manager – now what do you do? appeared first on Packet Pushers Podcast and was written by Michael Bushong.