A Damn Handy Catalyst Switch Command

When it comes to working with Cisco’s Catalyst switches, there are a handful of commands that get used pretty frequently to tell what’s going on.  I’m talking about after configuration is done, and when you come back to a switch later on for whatever reason to troubleshoot or verify operational parameters. I won’t be telling you anything here that isn’t already in a slew of Cisco docs, but I am working up to a specific point.

These are very common in my world:

  • Show interface (status, counters, errors, etc)
  • Show power inline (PoE info)
  • Show CDP neigh/show LLDP neigh (connected network devices)
  • Show mac address-table (L2 addresses of connected devices)
  • Show log
  • Show VLAN (VLAN database for the switch)
  • Show run (how the switch is configured)

The list goes on, and as most of you reading this know there are also variations of the commands listed that get you more granular information- like detailed information per single interface, expanded CDP details, only the last so many log entries, etc.

Big deal, right? This is pretty basic stuff, I realize. But at the same time, I do feel compelled to give a call-out to one command that I’ve come to truly appreciate:

show interface switchport

This gem tells you a lot about an individual interface and is handy as heck when odd things might be afoot with VLANs. (It recently helped me get to the bottom of a VLAN issue involving the murky mystical VLAN 1 on a Catalyst 3650).

Here’s one instance from a production switch:

#sh interfaces gig 1/0/32 switchport
Name: Gi1/0/32
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 8,170
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none

Now contrast that with the simpler [sh run interface] command for the same port:

interface GigabitEthernet1/0/32
description pci test or ACS
switchport trunk allowed vlan 8,170
switchport mode trunk
storm-control broadcast level pps 2k 1.5k
storm-control action shutdown
storm-control action trap
service-policy output TACTEST

So, the [show run] command just scrapes the surface of the actual  bigger VLAN paradigm in play for interface, while [show interface switchport] brings all of the VLAN-specific information out into the open, possibly revealing parameters not obvious through the other commands.

It’s the little things, sometimes… I like this command a lot where multiple VLANs are in use.

The Other Intent-Based Networking

Anyone who is in networking and who knows me is likely aware that I find a fair amount of fault with “Intent-Based Networking”. It has rubbed me wrong since I first heard it as the latest Cisco campaign, having been through many other flavors-of-the-month through the years. I’ve struggled to find within myself exactly what about Intent Based Networking has been pissing me off, but admit that this bogeyman in my mind has been elusive… very hard to pin down. Yet something has been stuck in my craw, I tellya.

Is it the sea of buzzwords that came with it? Is it the coincidental timing of this blog that asks us to swallow that subscriptions somehow equal innovation? (Sorry Cisco- that is a ridiculous stretch, even for you). Or this article in the same time frame telling the world all the ways Cisco is turning up the marketing heat? Sure, put it all together and to me- a customer frustrated by code bugs, feature bloat, corporate bloat, mixed messages at various Cisco levels, and the way that staying a large Cisco customer smells more expensive now than it ever has- and all of that adds to the feeling of being smothered a bit. But even all of THIS isn’t the root of my revulsion at Intent-Based Networking.

But I figured out what is bugging me about Intent-Based Networking. (It came to me like a bolt out of the blue when I was playing Sock Guy with my pug dog.)

Before I get there, let’s take a detour to this Network World Article. I have only recently learned that Intent Based Networking is not just an obnoxious marketing slogan from Cisco, but it’s also recognized as a bigger thing that I had simply never heard of in this context by that name. From the article by Brandon Butler:

Gartner Research Vice President Andrew Lerner says intent-based networking systems (IBNS) are not new, and in fact the ideas behind IBNS have been around for years. What’s new is that machine learning algorithms have advanced to a point where IBNS could become a reality soon. Fundamentally, an IBNS is the idea of a network administrator defining a desired state of the network, and having automated network orchestration software implement those policies.

“IBNS is a stark departure from the way enterprise networks are managed today,” Lerner explains in a research note describing IBNS. “Currently, translation is manual, and algorithmic validation is absent… Intent-based networking systems monitor, identify and react in real time to changing network conditions.”

It goes on to say that IBNS, as a generic construct, has four basic aspects: Translation and validation, Automated implementation, Awareness of state, and Assurance and dynamic optimization/remediation.  Those don’t belong to Cisco, they are the make-up of the general concept of Intent Based Networking. It’s a good article and worth reading.

So back to my angst and irritation. I’ve identified two-co-equal notions that steam my clams when I hear Intent Based Networking, as laid on thick by Cisco.

#1 Irritant. I, and others, have written about being a bit insulted by “AI” as a fix to everything in networking. No one with common sense and a pulse denies that machine learning and artificial intelligence aren’t powerful concepts that can be transformative if implemented right. But… Cisco, Mist, and others tend to send the vibe “our shit is great because of AI and machine learning- we have the right buzzwords and those buzzwords alone would have your wallet salivating! Without this new magic, you suck and your networks suck and you are lost at sea and you have soooooo many problems!”

The problems with that? Some of us design and run really good networks and aren’t thirsting for some mystical deity to come scrape the dumb off of our asses. And… many of the companies and individuals behind the new network magic don’t have stellar track records of getting code and actual customer needs and wants right. To be forced into Intent-Based Networking as the only real evolutionary option does create some discomfort. The new stuff is priced way too high for what is and will remain essentially beta quality in many cases.

#2 Irritant. I’ve heard nothing in Cisco’s marketing about the other Intent-Based Networking. This is the one where CUSTOMER INTENT is for the network to actually and predictably work, with minimal code bugs, free of a gimmicky feel, and with a price structure that doesn’t write out the words “Fleece the Customer” in the sky with a smoke-writing bi-plane. What about OUR intent? Stability, predictability, and no bullshitty licensing paradigms that make sure we never really own what we buy- pretty sure that summarizes the intent of most customers… Like having a network that isn’t the cause of most of it’s own problems by the vendor not shipping problematic code? That’s intuitive, no?

Sometimes words are just words, but put “Intent Based” next to “Networking” and Maslow comes to mind- the foundationally important stuff is what the customer thinks about first.

THIS “Intent Based Networking” is more important than the other one from where I sit. The two notions don’t have to be mutually exclusive, but it feels like they are right now. From the customer perspective, we don’t just pivot from years of erratic code and odd TAC engagements to a brave new expensive and Intent-based world without great skepticism because Cisco’s new marketing army says it’s the thing to do. Tone it down and and talk WITH us, not AT us.

There- now we’ve solved it. I actually feel better getting it out.

(And don’t even get me going on the Network. Intuitive.)


Hype in the Pipe- Wear Your Butthole Smoke Guards Going Into 2019

Lest ye allow smoke to be blown up yer kilt, don ye reality filter agin’ the vapors o’ San Jose.

– Old Scottish Proverb

These are exciting times to be in the business of networking. Whether the topic is wired, enterprise wireless, cellular or WAN, it’s all getting faster, bigger, and more complex. I won’t say better, because more complexity doesn’t mean better in all cases. Each technology and product story line needs to stand on it’s own merit, and as users and system owner/operators, we need to not assume that new+complex=better in all cases. Maybe it does, maybe it doesn’t. But that complexity isn’t going away, and as we head into 2019 I’m here to offer you what I see as some of the most glaring areas where you’ll want to look past the vendor hype and really find what matters to your environment.

The Kool Aid will be flowing like an avalanche coming down a mountain in 2019. You’re neither obligated to drink it all, nor to keep it down if you do sip some and decide you don’t care for the taste.

Rent-to-Own Rent-to-NEVER-Own

In a really warped way, this is pure genius. That is, if you’re on the receiving end of the cash flow. You buy a product, you buy support for the product, you buy licenses, then you re-buy those licenses every X years or… something happens. Something bad. Something that will impact your operations. Maybe the network ceases to function, maybe you no longer get support on buggy products. The new model in Silly Valley is you never quite stop paying, and so never really own “your” gear. To add insult to injury, blazer-clad corporate types push out blogs saying that subscriptions are how you get access to INNOVATION (cue the angelic background sounds) and so you are gosh-darn lucky to be part of the new Ransomed Innovation paradigm.

Takeaway: Cost models are changing, and in some cases are getting downright fucked up. Make sure you truly understand the upfront and long-term costs as you get into new equipment.

5G is the Wireless Connectivity Paradigm of the Future
No- strike that- 802.11ax is the Wireless Connectivity Paradigm of the Future
Uh- hold on… it’s 5G!
Ah shit… um- no, it’s Wi-Fi 6…

There’s little to be done here, short of maybe taking the 802.11ax marketing folks and the 5G marketers to THE OCTAGON  for a cage fight. It’s going to be a long year of hearing how each one is THE wireless technology for the future. To me, they are both right and both wrong, and as with all cases that marketers don’t want you to critically think about, it will always depend on the specific situation and circumstance.

In these tit-for-tat one-upmanship games, you can rely on the 5G folks to never really come clean about the fact that their baby is still a metered offering, and the 802.11ax-ers will tout phenomenal speeds that come from channel widths that none of us in the real world can actually use. Ah well…

802.11ax Will Bring It’s Own Brand of Hype

As I type this blog, I’m connected to a major vendor’s beta 802.11ax access point. My laptop is 11n, my out-in-the-country ISP connection is fairly slow, and I have no 802.11ax clients to connect with. This equation won’t change for me for at least a year at Wirednot HQ. But in that year, we’ll see early .11ax products, some adventurous enterprise adoption, and LOTS of hype about why you need to go to .11ax. All of the exciting parts of the standard will be touted along with aspects that couldn’t be used anywhere outside of a lab environment. There will be a frantic false sense of urgency created by marketing that needs to be met with reality. When I finally get to the point where I have my thousands of users on 802.11ax, I’ll be feeling pretty good. But it could also take years to get there…

In an environment where high-performing STABILITY is key, I had to wait over a year to deploy 802.11ac Wave 2 APs after my vendor released them because of ongoing code issues. Just like with the orchestration thing mentioned above, I have no reason to believe- no precedence to refer to- that my vendor will get 802.11ax right on Day 1. But they will certainly price it as if it were stable and wonderful. Beyond limited beta, I’d expect a real rollout to happen for me after the dust settles on the early adopters. Oh, and after a fair number of 802.11ax clients show up. Meanwhile the hype drum will beat on.

People are Soooo Stupid, So Let’s Help Them Stay That Way- and Then Further Confuse Them!

Somewhere on another planet, the Wi-Fi Alliance continues to drift further away from the course we actually need them to be on. Citing the “naming” of 802.11ax as “Wi-Fi 6” to be a move that will help customers somehow understand… something or other- the Alliance continues to ignore a lot of important issues that would bring more clarity to customers than just throwing silly numbers at wireless standards. We still have single-band client devices being produced, no clear delineation on device packaging between consumer and enterprise-ready gear, and a laundry list of things that ought to be tested under the heading of “interoperability” but that aren’t.

On the network side, it’s getting all about “orchestration”.  Using new software-defined magic, switches, routers, and APs will pop to life and never be configured wrong by human hands again! This actually sounds good… except that the underlying wizardry is still coded by… human hands. And in certain cases the vendors that are touting the orchestration options have horrific track records when it comes to bugs. Will that same bug-tolerant mentality make it in to the new magic? And if we are relying on that new magic, how hard will troubleshooting our own environments become when the orchestration itself spins out? Does this whole framework push us deeper into Vendor Lock and Rent-to-Never-Own? I really hope that this area really does live up to it’s hype- but there is zero reason to trust that specific vendors will get it right in their rush to market. Tread cautiously, y’all.

Be Hopeful, But Be Skeptical

Soooooo much is changing right now in the network world. You don’t just buy access points and controllers or a cloud dashboard. Now, it’s all about the Super System- NAC and Analytics and SDN and Fabric and blah blah blah. If you’re not in, you’re not hip, right? I guess it all depends on your version of “hip”. Like I said, these are exciting times, but marketing ALWAYS gets ahead of what can be delivered, and the early version of anything should be looked at with suspicion when big dollars are on the line. 2019’s hype is going to be interesting- but I encourage you to use it responsibly.




It’s Time Has Come: So Long, #WIFIQ

A few years ago, I tried an experiment on Twitter. I threw out a question related to wireless networking, hoping to get a few people to reply and to start an exchange of ideas on that topic. Then the next day, I did it again. Then… one of the smartest, nicest gents I’ve ever met said something like “people seem to like this daily mini-roundtable- why not give it a hashtag and a date?” So I did, and #WIFIQ was born. If you’re not familiar, here’s how I described it after it caught fire.


It’s been a great run. There have been sooooo many excellent conversations spawned by the #WIFIQ thing, with new friendships made and lots of side conversations along the way.  I didn’t realize quite how much #WIFIQ was valued by other people until February 2018 found me being awarded the WLPC Person of the Year award, for contributions to the WLAN community (including #WIFIQ). It was quite humbling to hear from dozens of people afterwards just how much they looked forward to the daily question, whether they participated or just followed along.

Now, I find that I’m kind of  burned out on getting a fresh #WIFIQ readied for every Monday-Friday and then trying to keep the conversational pot stirred throughout the day. It has been my honor to do it, but I’m ready to close down the operation before I start to not like doing it anymore. To those frequent flyers who gave their own participation often, I thank you very much for helping me to carry the ball during this long-running game. For anyone who has ever thrown out an answer, asked a question, or just followed along, you made this venture just a pleasure for me to do for this long.

Thank you, everyone.

One negative by product that came along the way- I’ve come to realize just how intolerant of other opinions some people can be. Whether the topic is some discreet Wi-Fi-related concept, religion, or politics, I’ve seen (and experienced) friendships lost over differences of opinion.  I’ve been thankful for those who can have unpleasant discussions but then walk it back from the edge to be civil to each other tomorrow, and have been astounded when others can’t- those who would rather burn a bridge and go into full-attack mode than concede that their fellow man is entitled to their own opinion. Ah well- human beings can be knuckleheads (that’s all of us).

Going forward, I hope that some of you might use the #WIFIQ hashtag to invite others to engage in conversation. It doesn’t have to be the formal daily thing that I orchestrated, but might just work as a “hey- can anyone comment on THIS?” kind of call to action at any time of day. In my mind it makes sense, but whatever.

I hereby set #WIFIQ free, to be what it will.

Thanks again, and I’ll still be around chattering where I have something to say.



Enhance Your Wi-Fi Mojo With Old-School Radio Hobbies

I have this odd love of some really arcane signals. With a modest but decent receiver from Tecsun (the PL-880), I take advantage of the winter months in the northeast (less atmospheric electricity and no thunderstorms) to “hear” these quirky Longwave signal churn out slow Morse Code identifications. It’s utterly addicting to the right-minded radio geek, and also draws large parallels to what goes on with Wi-Fi that help reinforce my WLAN foundational knowledge.

For wireless networks , we know that output power, antenna choices, the environment where we’re operating, and the capabilities of the client devices all contribute to whether Wi-Fi is “good” or “bad”. If the signals can’t get through, then the microprocessors involved can’t turn those signals into data. Let’s talk about what it feels like to listen to NDBs for a bit, then how that relates to Wi-Fi.

I live about an hour south of Lake Ontario in the middle of New York state. With my beloved Tecsun PL880, I recently received an NDB signal from Pickle Lake’s little airport in Ontario Canada. This location happens to be several hundreds of miles away. The beacon transmitter (considered a “navigation aid”) at the airport generates a fairly low-power cone of  signal into the sky, more or less straight up (that’s the non-directional part of “NDB”). The intelligence in the signal is simply slow Morse Code continuously looping the letters Y-P-L. See this link for  information on the airport.

Pickle Lake

Given that any beacon is typically low powered and pointed straight up, finding them on the air from afar is a sport unto itself. Longwave spectrum sits below the AM broadcast band, way down where frequencies are measured in kilohertz.  It’s absolutely cluttered with man-made signals, and is at the mercy of natural electrical interference, like lightning strikes (called “static crashes” int the radio world). Yet I was able to discern that slow Y-P-L signaling from across a huge Canadian province and a Great Lake, making it an accomplishment as a signal-chasing radio hobbyist.

If you’re not familiar with Morse Code, that Y-P-L formats like – . – – / . – – . / . – . . (dash-dot-dash-dash/dot-dash-dash-dot/dot-dash-dot-dot).

In 802.11 WLAN, specialized modulation helps to ensure that the important signals prevail despite RF conditions being crappy enough to kill narrow-band signals. I see Morse Code is somewhat akin to spread spectrum when I’m chasing NDBs as the dots and dashes can often be heard through really bad conditions that would utterly destroy voice signals. (This is actually why Morse Code was created and used as a mainstream long-distance radio communications mode for so long.)

When Wi-Fi signal quality is degraded, data rates will decrease. When I hunt down NDBs like Y-P-L signal, I might have to listen to each for several minutes and manipulate the filters on my receiver before I know what I’m actually hearing- and sometimes I just can’t quite clarity.  For this and other radio activities, my own ears and mind are the actual microprocessor. Call me silly,  but each beacon identified is like catching a nice fish and brings it’s own little flicker of excitement. Here’s a great list of Longwave NDBs out there to chase, and there are many other lists to be found online.

For improved reception, I could connect my PL880 at to a better antenna, just like in Wi-Fi. I could improve my “data rates” (or words-per-minute copying) by using better filters and practicing my Morse Code more. This would make me a better “microprocessor” in this activity.

Really geeky stuff, eh? I have no problem wearing that label. I also know that there are other radio nerds out there in the WLAN community, as well as those who want to learn more about radio “stuff” beyond Wi-Fi. For those folks, I’ll be teaming up with Scott Lester to present “Radio Hobbies for the WLAN Professional at the 2019 WLAN Professionals Conference. Sign-ups start mid-December, and I hope to see many of you there!


Dear Dubai Accountants, I’m Not Hiring

What do Mohasin, Afsal, Jinshad, Tibin, Alex, and Ajo all have in common? Each happens to be just one of the many, many more accountants from Dubai who wants to come work for me. The thing is, I already have an accountant. His name is Dan, and he’s in Baldwinsville. I see him once a year for my taxes… always ridiculously early in the morning, and we have coffee and great banter while we slog through the tax preparation process.

Sorry, Mohasin- I’m not about to rock that boat. Dan’s the man.

And that’s really the sum total of my accounting needs. I wish I could help the throngs of accountants from Dubai that somehow got my name… Evidently there is some misinformation afoot about the Badman & Badman financial dynasty that keeps these good folks interested in potential employment with me, but I’m here to tell you- I got nothing for you. I have no opportunities.

Hmmm. Let’s rethink this. I have nothing in accounting  available. But there are a couple of odd gigs I might need someone for if they have an open mind. All you Dubai folks, give these some thought- if you’re willing to stretch your comfort zone (or discomfort zone, as it were), I might be able to help a couple of you out with some short-term resume-building work.

  • Body Double For Upcoming Conference. I have a conference coming up in February, and there is this one guy who I don’t trust to stay the hell away from me. I’m considering using a decoy stunt double to better my odds of avoiding contact with Bender. The conference is in Scottsdale, Arizona, which can be problematic for me as well. When I was a child, a fortune teller once predicted I would someday be shot in the groin at a Jack-in-the-Box in Scottsdale. You can see where having a decoy might come in handy on numerous fronts. I would require you to fund any cosmetic surgery required to fool Bender and whoever is waiting to pop a cap in my ass, but the life skills gained on this venture will absolutely make you more marketable.
  • Squirrel Finder at Camp. For years I’ve been trying to get what I assume is a squirrel out of our camp attic. I’ve sealed up like six holes in the eaves, and probably have a metric ton of poison sprinkled around the attic. (I’m starting to wonder if maybe a woodpecker is collaborating on the squirrel’s project, because the entry holes are impressive- like if a beaver was in a bucket truck to get up that high.) Yet there is evidence in the ceiling in the bathroom that something is still running around up there. It’s driving me absolutely nuts. Take care of my problem once and for all and there is $100 in it for you.

Beyond these openings, I really, really don’t have any accounting work. Maybe you guys could spread the word there in the Dubai accounting circles?