So, remember when I said that I would be doing these once a week?
Yeah, that was before life came along and decided that it had a different plan in mind!!
Apologies for the long silence. I actually started this recording well over a month ago, but tonight is the first night in a very long time that I’ve had time to actually sit down and put the finishing touches on the recording. We won a large services contract for a very large company (Fortune 10) to roll out new network segments at their datacenters across the US. So I’ve been on the road constantly, dealing with 11 PM to 6 AM change windows, change management meetings, status reports, project managers, and all kinds of “fun” stuff on top of actual network engineering… and then on top of that we’re buying a house and moving to a different state. A huge shout out to my wife for being a rockstar during this trying time.
Without further ado and rambling from me, here’s Episode 2 of the Packet Wrangling podcast. This one covers common wireless architectures and the pros and cons of each. Enjoy!
So, you’ve built your predictive design and now it’s time for the rubber to meet the road – the infamous AP-on-a-Stick survey. To perform this piece of your wireless design you’ll need a lot of “unique” gear… tripods, laptop shelves, tons of wireless adapters, APs, and enough battery power to get you through the day.
When I was building out my survey kit, I noticed one flaw with the “professional” battery packs built for wireless surveys. Beyond being very bulky and expensive, the majority of them only support 802.3af. The newer and larger APs often prefer 802.3at (also called PoE+) these days. In some cases, they can use 802.3af, but they turn off several spatial streams in the 2.4GHz radio to adjust for the lack of power.
That’s less than ideal, isn’t it?
Thanks for the Internet, I was able to cobble together a pretty affordable battery pack that supports both 802.3af and 802.3at and lasts an incredibly long time. Here’s the pieces and parts that have worked for me:
The total will run you about ~$140.00 and it lasts for an extremely long time. Just power up the Intocircuit, hook it up to the Tycon converter using the adapter, and connect your AP. I’ve used it for several gigs now and despite looking a little “homemade,” it does the trick.
There’s been many exciting announcements at the Atmosphere 2017 conference and it’s been really great to meet a bunch of the fellow wireless twittersphere. All in all, definitely worth the time to attend.
Many other wireless minds have been covering a lot of the “cool” stuff – new ArubaOS8, new machine learning analytics with RASA and Niara, new monitoring tech with Airwave Glass and Clarity Synthetic, crazy new ways of wireless with 802.11ax, and more.
But one thing that really stood out to me personally is the new Univeral AP code that’s being rolled out to their new APs. Those of you familiar with Aruba know that there used to be two primary “versions” of hardware – Instant and Campus. Campus APs were meant to be used with a controller and they were sold without region locks, assuming that the controller would handle the regulatory compliance. The advantage was that they locked in real quick to a controller with auto discovery. The disadvantage was that there wasn’t a supported way to flash them into an Instant system, so hope you like those controllers you got there. The Instant APs had more intelligence at the edge and had region locks baked in at order, and they could move back and forth between Instant and Controller architectures – but to have them discover a controller required manual intervention, meaning that converting a large scale Instant roll-out into Campus methodology was a pain in the ass. Both were sold at the exact same price point.
The new “Universal” code means that an AP can become either a Campus or Instant AP from birth without any funky conversions. The self discovery process has become much longer though, so to spare you from any hand wringing as the APs slowly toddle towards configuration, here’s the new boot process that was shared at Atmosphere 2017:
Static master assignment preconfigured
DHCP based discovery using DHCP options assigned by DHCP server
NOTE – This uses option 43 to give the controller IP address to the AP
NOTE – make sure you don’t have another service utilizing DHCP option 43, I have seen that cause random problems with redirecting the AP to something completely unrelated
NOTE – The AP has to have basic DHCP and DNS discovery for any automated discovery to tick. If it doesn’t, it will reboot constantly. Yes, you will need to edit the CLI config to allow APoaS site surveys
Aruba Discovery Protocol based discovery
NOTE – this only works if either the controller is in the same broadcast domain as the AP or if multicast forwarding is configured (multicast address used is 22.214.171.124)
DNS based discovery (this is what Aruba recommends as best practice)
NOTE – the AP will look for aruba-master
Instant Virtual Controller Discovery
NOTE – this means that the AP will reach out in its own broadcast domain with the PAPI protocol to find a local Instant AP that is elected as VC
Activate Match Airwave
NOTE – Activate is Aruba’s cloud based provisioning service. The AP must be able to communicate on the Internet for this step or the following two to work.
Activate Match Central
Activate Match CAP/RAP
Broadcast Instant Provisioning SSID
NOTE – And here’s where you are off to the races with the Instant platform!
Quite a journey, isn’t it? Nice that we’ll be able to purchase as single SKU now though.
No podcast/blogpost this week, as I’m out living it up in Nashville with some of the best and brightest minds in the wireless networking industry! They’ve revealed a lot of exciting new features in just the first day, ranging from the ambitious machine learning based security on the internal network to the practical new wired tunneling techniques and multi-zoned APs. And yes, the presentations are more than just marketing fluff. I’ve already attended several great sessions, including a technical deep dive on 802.11ax, with many more scheduled for the next several days. More to come.
Also, the ongoing Amazon S3 outage just proves that the cloud really is just someone else’s computer.
Welcome to the first Packet Wrangling podcast! In this episode, we take a quick look at spectrum analysis technology and discuss why it’s important both for new deployments and to troubleshoot existing installations.
I’ve been involved in a number of planning meetings for IT infrastructure refreshes – servers, storage, WAN, networking, wireless, you name it. Most of the time the requirements are more or less well-defined and well thought out… number of hosts, exact processors, memory requirements, connectivity to the storage arrays, VLAN assignments, and so on. All the I’s have been dotted and the T’s have been thoroughly crossed. But there’s always one noticeable outlier – the wireless network.
“Oh and… maybe 10 APs? Maybe 12 just to be safe.”
It’s 2017 and we can simulate just about everything. Why are we still using primitive thumb based rules for the wireless network?
If you guess too high, you’re out a sizeable chunk of money and you may not even get additional bandwidth.
If you guess too low, you’re going to have slow/dead zones. And good luck getting management to not only buy more APs in a separate purchase, but also to pay for the cabling.
CCI is a real thing. Adding more APs does not necessarily add bandwidth. It’s the laws of physics!
Just “cranking up the coverage” doesn’t always work either. Client radios are only so strong, and the conversation has to flow in both directions.
It’s ill advised to go with the “low capacity” model and just throw extra APs up in high density areas as needed, again due to the laws of physics. Be sure to choose beefy APs for the auditoriums, gymnasiums, and so on.
One AP per room is not a valid design principle.
A design will help you determine how to balance building for 5GHz coverage while not creating a trainwreck in the 2.4GHz spectrum (hint: spectrum analysis isn’t a bad thing to have running in the background)
Wireless is how we connect now. If your wireless performs poorly, it doesn’t matter how slick a datacenter you’ve built to serve up the applications, people will only remember that it didn’t load properly.
There are programs available that can fully simulate wireless propagation through all kinds of floor plans and allow you to effectively preview the performance of your wireless network, all from the comfort of your own home. While it’s still advised to take some onsite measurements in complicated deployments, a predictive survey will give you a much better starting point than the infamous “1 AP per room” design.
I’ve been using Ekahau Pro myself and it’s been a life saver.
You probably won’t be refreshing the wireless infrastructure for another five years – why not ensure that it’s going to work well?
Thanks for reading this slapdash semi early morning rant. And no, I am not being compensated by Ekahau for this blog.