ubnt

UBNT Unifi upgrade issues

Recently my best friend installed some unifi access points in his home.  We had ordered a 60W unifi switch, a couple of AP-LR, and a couple of AC-Lites.  These were ordered and sat for several months until we could get around to installing them.  Upon installation, the AC Lites were adopted and had to go through the normal upgrades to bring them up to the latest version.

However, the AP-LRs were used and had very old firmware on them and would not upgrade properly. They would adopt but not upgrade.  We fixed this in the following ways.
1. We Factory reset the APs. At this point, they grabbed DHCP from the local network. Quick ssh into the AP verified it had internet connectivity.

2. I was able to find some old firmware on the UBNT web-site.  We issued the following command to each LR AP

upgrade http://dl.ubnt.com/unifi/firmware/BZ2/3.7.58.6385/BZ.ar7240.v3.7.58.6385.170508.0942.bin

the “HTTP” is important to note.  If you copy the link directly from the UBNT website it has https in it.  The older firmware blows an error due to invalid certs (fixed in newer versions).

Once it came back we were able to upgrade from the controller.

AirFiber 4.10 is out

Important notes
  • Please update far end of a link before the near end
  • Please refresh browser cache when logging into a v4.1.0 unit for the first time
  • UNMS cannot upgrade airFiber firmware loaded with pre-beta8 firmware (i.e. -beta7, etc.)
  • If you are upgrading from pre-v4.0 software, your password (after upgrade) will be the first 8 characters of your pre v4.0 password. If you chose to downgrade, please ensure that your password is no longer than 8 characters or you will be locked out of your unit.
Features
  • Added additional modulation rates (3x, 5x, 7x, 9x, 11x)
  • Improved throughput capacity (improved modulation performance)
  • Added support for UNMS
  • Added telemetry reporting (optional)
  • Changes to support Apple SSL certificate location rules
  • Updated default https certificates validity for 18 years
  • Added Paraguay and Swaziland country codes
  • Telnet Server port number now displayed on Services tab when using default number (23)
  • Added alert box when Receive Target Power is enabled
  • Build number now shown in system tab
  • Firmware version now displayed with product ID (i.e AF11 vs AF09)
  • Assorted web changes to colors, initial login screens, updated EULA
Improvements
  • Manual browser refresh not required when upgrading FROM 4.1.0
  • Updated SNMP MIB
Bugfixes
  • Detect and recover from OTA management traffic lockup
  • Detect and recover from user traffic lockup
  • Fixed issue where capacity graph showed 2x capacity when there was no GPS signal at the timing master
  • Fixed issue where GPS process would use 100% of the CPU
  • Fixed issue where RF link would repeatedly reset if Ethernet port was disabled
  • Addressed issue with moving (jittery) labels around signal strength graph
  • Corrected conducted power reading when using Receive Target Power
  • Fixed issue with Carrier Drop Operation where unit would not come back if Block Data After Pulse was enabled
  • Fixed issue where disabling Management VLAN after upgrade from pre v4.0 could corrupt networking configuration
  • Fixed SNMP reporting of frequency (SNMP now reports frequencies in MHz)
  • Fixed Static IP gateway address usage (was ignored if configured with v4.0.x)
  • Fixed GUI issue where deleting link name and pasting in a replacement would not work
Known issues
  • If you are upgrading from pre-v4.0 software, your password (after upgrade) will be the first 8 characters of your pre v4.0 password. If you chose to downgrade, please ensure that your password is no longer than 8 characters or you will be locked out of your unit.

Official Page and Download links here

Capacity of a UBNT AP vs the number of clients

Note: I am in the process of updating this for AC based radios. This was published in 2014, but much is still relevant.

Almost all the time I get asked: “How many clients can an AP handle?” . My answer is always a very long and drawn out one. There is no set in stone answer. There are many factors which can affect this. I will go into some of these and then explain how to calculate this.

Some things that we will assume.
1.You are calculating on an 802.11N Ap with some kind of polling (TDMA, NSTREME, AIRMAX, etc)
2.You know the MCS values and/or data rates at channel widths.
3.When I say in an ideal situation I mean basically in the lab. This is our baseline. This means no outside noise, everything is working properly, and all the connected clients are excellent.

Before I get into what affects how many clients can an AP handle we need to shift our thinking a little. We don’t think in terms of how many clients can an AP handle. We need to think in terms of how much capacity an AP has. This is very important to think in these terms. If you do so things will become more clear and more quantifiable.

So now, on to what affects the total capacity of an AP.

1.The channel width. In and ideal situation you will get more Capacity out of a 20 mhz channel than you will a 10mhz channel.
2.Noise. In the real world you will have interference. If you have interference the noise floor drops, customer signals can’t reach maximum modulation, and there are retransmits.
3.Plain old signal. Things such as trees, distance, fresnel zone, and antenna gain all affect signal
4.The speed you are giving to each customer.
5.Overselling. The concept of overselling has been around since the dial-up days. You are betting your customers are not all online at the same exact time doing the exact same stuff. So you can oversell your capacity. I will explain this a little more in a bit how this factors in.

Okay, so let’s dive into this. I am going to use a Ubiquity Rocket M5 as an example. Again, this can be applied to any polling type N radio.

Say we have a Rocket M5. At a 20MHZ channel the best modulation this M5 will do is MCS 15 at 130 Megs of over the air. What do you mean Over the Air? Well there is a difference between actual throughput and the Wireless Data Rate (aka over the air). Your actual throughput/capacity will be 1/2 of the over the air rate minus a little for overhead. I factor in 10% overhead for easy figuring.

Back to our figuring. You have 130 megs of capacity on your AP in an ideal situation on a 20 mhz channel. If we do our math:
130 / 2 = 65 Megs of Capacity to sell on the AP.
Now here comes the overselling part.
If we oversell at a 2:1 ratio we have 130 Megs of capacity on the AP.
If we oversell at a 3:1 ratio we have 195 megs of capacity on the AP.

We can do higher ratios, but it starts to become a moving target. With the spread of Netflix, Youtube, Hulu, and other streaming services the average customer is sucking down more and more bandwidth for longer periods of time. Think of a restaurant with so many tables. If your customers are staying longer and longer, you don’t have as much seating capacity to turn over for new people to sit down and consume your food. This is for another blog post.

So, let’s say we are overselling at 3:1. We have 195 megs of capacity. We now need to think about what packages we are selling to our customers. If they are all say 5 meg packages, this means we can safely sell 39 connections to the AP. 195 / 5 = 39. You can figure up the math if you have 3 Meg, 10 meg, or a mixture.

Now to the real world (aka why do my customers hate me and my AP sucks?).

The following is a real AP in the wild.  Blacked out to protect the innocent from script kiddies.

ubnt-main-screen
Couple of things to Note (circled in Red).

20 MHZ Channel
Capacity at 45% . This is more important than anything, even CCQ.
43 clients associated.

Let’s apply our math we learned earlier. We know a 20 mhz channel nets us MCS15 – 130 Megs

Here is the kicker.  Our capacity is at 45%.  This means we only have 45% of 130 megs of Over the air capacity.  Take this in half (130 / 2= 65   45% of 65 = 29.25.
This means all 43 of these customers are sharing 29 megs of capacity on the AP.  And the quality isn’t the greatest (37%).  So this means there are retransmissions going on between the client and the AP. The client can’t talk as fast as it is capable of in most cases. This means you can’t oversell the AP as much due to the quality of the signals being poor.  It is important to note I am talking about the quality and capacity of the signals, not signal strengths.

If those 43 people are all paying for, let’s say, 2 Megs download.  That means your AP needs to support a minimum of 86 megs. Thats without overselling.  We only have 29 megs in the current state!

We need to get those capacity numbers up.  How do we do that?

1. Channel selection. A noisy channel will drag everyone down.

2. Antenna gain.  This can be done at both the client and the AP.  A higher gain or better quality antenna can cause the clients to “hear” better.  You might not get an increase in signal strengths, but you are looking for an increase in quality. I use a loudspeaker metaphor.  You can hear a loudspeaker from a far distance, but you might not always be able to make out what is being said.  If you can somehow make out what is being said more clearly, then you don’t have to have the speaker turn up the volume.

3. Shielding. This helps eliminate the amount of stuff a client or AP hears.

4. Channel Width.  Sometimes dropping the channel width down can increase signals, thus raising the overall capacity.  Keep in mind it will lessen the overall capacity of the AP.

5.Simply getting rid of customers that shouldn’t be installed.  We have all done installs that were iffy.  These can drag down the overall capacity.

I hope this has helped understand.  The biggest thing I want you all to take away from this is think in terms of the amount of capacity you have to sell, not the number of connections.

Ubiquiti launches Speedtest Server/network

https://blog.ui.com/2019/08/13/ubiquiti-launches-a-speed-test-network/

Ubiquiti launches the Ubiquiti Speedtest, the first public test network integrated with enterprise network equipment. Ubiquiti Speedtest comprises a network of test servers and built-in speed test capabilities. Reports include uplink/downlink throughput and latency. Sharing the results is easy via email or social media.

It appears you can run this on a Ubuntu server or VM. They have an installer and a docker image.   You can do browser-based speed tests or their WiFiman App.

Tests may run over LAN, Wi-Fi, or mobile networks. Ubiquiti Speedtest uses Ubiquiti test endpoints and provides automated and manual test target selection. The automated selection uses a combination of geolocation and latency measurements for determining the best servers. The algorithm may use several parallel endpoints for the best measurement accuracy.

Preseem releases access point paper

https://www.preseem.com/2019/06/wireless-access-point-market-insights/

Unlike spec sheets from manufacturers, Preseem collects real-world data from access points in all kinds of deployments and analyzes statistics at a top level to offer valuable insights. So, as part of our Fixed Wireless Network Report, we calculated wireless access point market insights on market share, connected subscriber count, performance on QoE metrics like latency and much more…