Additional Alien mesh points degrading signal after each update


  • So far, after 3 updates since purchasing my second Alien to use as a mesh point I have been seeing the mesh link speed as well as the actual signal strength degrade with each update.

    When I bought the 2nd Alien a few months ago, I was able to consistently get 1Gbps on the link speed. After the next update, it was reduced to 900Mbps, and then down to 600Mbps. There have been zero physical and environmental changes as well as no new wifi neighbors. Now, with the 3.6.0 update, I am seeing 400-500Mbps. With the previous fw, my signal was a mild -51db... Now with 3.6.0 it's saying it's -64db... Why is this degradation happening and why is it getting worse with each update? I am worried that with the next update, the speed will further be nerfed. This is ridiculous to me.


  • This should be posted in Using Amplifi Alien rather than here. Nonetheless, you did not provide any detail for anyone to respond.

    How are your Aliens configured in Mesh (wireless or wired backbone) If they are wireless at what signal strength for each from each other (see app)?

    If you shut down (power off all Mesh Units) and power on the Main unit, and run a test, then what performance do you have?

    How are you determining your speed?

    What WiFi clients are you using and how are they configured?

    What link speeds are reported?

    How is your WiFi and AP configured (see my post in Release)?


  • How are your Aliens configured in Mesh (wireless or wired backbone) If they are wireless at what signal strength for each from each other (see app)?

    I gave a signal strength for the mesh point, which would indicate that I am using it in wireless backbone. See the above post for the signal strengths.

    If you shut down (power off all Mesh Units) and power on the Main unit, and run a test, then what performance do you have?

    I am not concerned with performance of the wireless network. I am concerned about the continuing degradation of the mesh wireless link speed and signal strength across firmwares between the main ap and the mesh ap.

    How are you determining your speed?

    I am using the mesh test directly on the touchscreen of my Alien meshpoint.

    What WiFi clients are you using and how are they configured?

    I have all kinds of clients, which all work fine. I do not understand why this would be relevant to the wifi link speed.

    What link speeds are reported?

    See the OP, I reported this in the post.

    How is your WiFi and AP configured (see my post in Release)?

    Network is configured with split bands. No router steering.

    Wifi 6 2.4Ghz: Manual Ch 11, 20/40Mhz
    Wifi 6 5Ghz: Manual Ch 100 (DFS), 80 Mhz

    No additional SSD's used and additional 5Ghz wifi radio is disabled.

    There are no wireless neighbors that interfered with the channel I have chosen and the system doesn't detect any radar.

    Automatic backbone switching is disabled (though if I reboot the mesh point, it will sometimes use the 2.4Ghz backbone instead of the 5Ghz backbone).

    802.11r, k, v enabled


  • Wifi 6 5Ghz: Manual Ch 100 (DFS), 80 Mhz

    Hi @cmdshft - do you see the same signal degradation with latest firmware while using a non-DFS channel on the same channel width setting?

    DFS transmit power is limited to 250mW
    Non-DFS channels from a router typically run around 950mW

    Depending on how far away a mesh point is from a router there will likely be a noticeable drop

    Using 160MHz channels for example will also drop signal strength over distance faster than 80MHz channels


  • Why are DFS channels limited to a lower power output?

    I will check shortly if I still have the same signal degradation. I also never used 160Mhz (and in my Alien's web-admin page, I can't even select 160Mhz for Wifi 6, only Wifi 5).

    Do you think that I would face any bandwidth issues by switching the bandwidth to 40Mhz or even 20Mhz on Wifi 6 5Ghz?

    EDIT: So, I switched to 40Mhz Wifi 6 5Ghz, and I switched to ch 157. My signal strength only slightly improved. I am now at -59db or -60db randomly. I am 100% sure that I was -51db on the last firmware (I check my network health often).

    I am really aggravated by these mesh point speed issues and Ubiquiti refuses to address this, I have brought it up to them and their support was supposed to do a follow up with me from the higher tech level engineering and they never did.


  • Hi @cmdshft - DFS is limited to "indoor use" by definition and capping transmit power to 250mW is part of the specification

    For general client WiFi access this isn't an issue as most mobile clients also limit transmission power to around 250mW since they can be used closer to the body and to optimize battery power

    Routers and and mesh points can use up to 1000mW on non-DFS channels in countries where the channels are not designated for indoor or low power usage (Canada for example requires lower power on some channels that the US does not)

    Mesh point wireless backhaul is a difficult balance on Alien because they have up to 8x8 MIMO available
    Cutting the channel width in half cuts throughput in half, but typically gains more range or a higher SNR at the same distance
    So it really depends on how well AmpliFi is controlling the backhaul, which is part of their secret sauce
    The Alien is also fairly unique going 8x8
    Beamforming also comes into play, and is not easy due to the Alien's tight antenna spacing

    I recommend the Duckware articles for more insight, especially...

    DFS is a nice option to have if you are in a very crowded environment, but has its drawbacks, especially for mesh points
    Mesh points using DFS channels are required by the FCC to also do radar scans and force the main router off of a channel if interference is detected
    Channel widths can help in some scenarios but eventually you are limited by either the Gigabit Ethernet switching or the packet processing capabilities of the SoC

    I personally have to use a 40 MHz channel widths because I am in a very very dense condo environment with a lot of unfavorable construction
    For my setup, I try to give the Alien as little to do as possible and balance range vs need (not performance)
    DFS, 160MHz, etc. are all just more work for the SoC to perform and manage with little benefit to my actual needs
    But everyone's setup is different, so best to work through your own installation step-by-step and not worry too much about what others are doing...


  • Okay, thank you for that info, I will look into it for sure.

    After switching my channel to 157 and making my bandwidth 80Mhz on the 5Ghz Wifi 6, I am now sitting at -59dBm. So it seems that switching to a non-DFS channel only made a marginal improvement. I am 100% confident that my signal is still worse than it was a few months ago, I was able to get consistent 1Gbps on the mesh link speed. Literally nothing has changed in my environment and as I posted before, there are no new wireless neighbors that would be interfering (the only wifi network that shares the same channel as me right now has a signal incredibly low that my network completely dwarfs it in signal, and it's always been that way).

    I'm still super annoyed because I have done everything that I can to make the link speed improve to how it used to be, the only way to do that now is to physically move the mesh point closer to the router in a config that doesn't really make sense to me. I even changed the country the router was set to, as it was set to Canada so I could use the Celsius temperature measurement. After you mentioned the bit about restricting signal strength in some counties like Canada and not the US, I decided to switch to test. It seems to have made no difference.

    The way my wireless network is laid out, my house is about 20ft wide by 60ft deep. I have my router on the second floor in my "gaming room" which is at the front of the house street-side. My second Alien is at the rear of the house on the first floor, mounted on the wall that literally has my backyard as the opposite side of said wall. There is a fairly clear line of sight to the router (the signal has to pass through the floor/ceiling from the 1st floor to the second floor and a single wall which is mostly hollow). I would say there is a total of 55ft between the two routers.

    In order for me to get the mesh point signal to be optimal, I basically need to move it where it would be 10ft away from the 2nd floor router, on the 1st floor. If I take it to the 2nd floor, I can achieve that at the 20ft mark just about (except there are no outlets that would make powering it convenient there, so that's why it's not on the second floor). Having the 2nd unit placed where it's optimal seems silly, because the main router does reach to the back of the house anyway. I have the 2nd router in the first place because the main router loses signal to our phones in the backyard, literally as soon as we step outside (because the house has aluminum siding). The 2nd router helps a great deal in providing wifi to the backyard, it's mostly for just entertainment purposes anyway (moving an Alexa speaker outside for example). If it wasn't for needing the signal to reach the backyard, I likely wouldn't even have gotten the second unit at all.

    Am I being too upset for losing almost half my mesh link speed over the last few updates? I feel like I am losing what I paid for. I experienced something really great and it feels like with each update, it gets worse and worse...


  • @cmdshft Is there any chance to run an Ethernet Backhaul at all? Or at least test this scenario. I am sure DFS with Alien team still has some work to do, but there are some limitations as well.


  • Am I being too upset for losing almost half my mesh link speed over the last few updates?

    Hi @cmdshft - no, but it can take a lot of work to diagnose and fix, so how much effort do you want to put into it?

    Are you for sure being negatively impacted by the installation as it is with the new firmware?

    Rolling back firmware, factory resets, utilizing the Additional 5 GHz radio with a unique SSID and a lot of testing and waiting for an environment to stabilize can be a PITA so make sure it is worth it

    If I were in your position I and I wanted to go down that rabbit hole I would perform the following (some will be controversial)...

    • rollback firmware to what previously worked
    • factory reset
    • start with the main router only
    • do not use a common SSID and setup 2 never before used SSID's
    • turn off band steering & router steering
    • enable the Additional 5 GHz Radio with a 3rd unique SSID that has never been used before
    • turn off everything in the main Web UI Advanced Settings (uncheck all)
    • enable QoS Latency Optimization and set both upload and downlaod limits to below your rated ISP service limiting the load on the CPU at least temporarily and improving latency if the internet is involved with any testing
    • enable the Beta options but do not install beta firmware
    • on the Beta Options page at least temporarily Forbid IgmpProxy Service & Forbid Fingerprint Service to start
    • disable UPnP and IPv6 at least to start with
    • do a site scan if possible and manually configure the 2.4GHz radio to channel 1, 6 or 11 @ 20MHz bandwidth
    • do a site scan if possible and manually configure the WiFi-6 5.8 Hz radio to a fixed channel @ 80MHz bandwidth
    • do a site scan if possible and manually configure the WiFi-5 5.2 Hz radio to a fixed channel @ 40MHz bandwidth
    • manually set up all clients you want fixed to the new 2.4GHz SSID making sure they are unaware of any other SSID
    • manually set up all clients you want fixed to 5GHz on the WiFi-5 Additional SSID making sure they are unaware of any other SSID
    • leave the WiFi-6 5.8 GHz SSID unused by any client so it is exclusive for backhaul

    Some of those items may seem odd or counterintuitive, but it's temporary for isolating the mesh backhaul
    Do some testing with clients on just the main router then...

    • install the first mesh point
    • test check and adjust to ensure your backhaul is performing as expected
    • you may need to move the main router or mesh point, even turning them slightly, move them closer or away from walls or objects, etc. so the Beam Forming algorithm can optimize the link
    • move the clients you need back onto the WiFi-6 radio and ensure the backhaul link is unaffected
    • rinse and repeat if you have more mesh points

    Once everything is stable and working the way you want it then you can play with settings if there is something else you want to optimize, like enabling the Common SSID if you need it, IPv6, roaming hand-off, etc.
    Take detailed notes of all of the settings then install a new firmware update
    See if anything about the new firmware changes the performance or characteristics of the mesh
    If something is off, perform a factory reset and try setting it up exactly the same again
    If something is still not right, then start changing channels or other settings to see what works, which may require another factory reset

    If you just can't get the performance you are looking for then there may be something in the background that AmpliFi had to change which you may not be able to control or overcome
    There is a lot of secret sauce magic in creating a mesh and so it may not ever get back to before
    Just implementing new security updates may affect performance

    If you are feeling generous, create Support Info files all along the way and then try to get AmpliFi to analyze them from before and after a change occurred that you cannot explain or overcome

    Then go have a cold beverage of your choice...good luck!


  • Yeah, i've already done a bunch of these things through my efforts.

    I just tested by leaving my Wifi 6 backhaul empty and it didn't make a speed difference sadly. That being said, that does tell me the Wifi 6 5Ghz backhaul is quite hefty and that's impressive.

    I guess I am just at the end of my capabilities to get it back to normal and it seems more like that it's on Amplifi/Ubiquiti's end. Hopefully they can push an update out sometime in the future that will help boost meshlink speed again.


  • @cmdshft I read with great interest your posts - I am observing the exact same experience. With this last update its been most difficult to keep the Alien Mesh point (I have two full-on Aliens, instead of the Alien/Mesh combo they offer) on a WiFi backhaul of 5GHz. I had to enable automatic backbone switching to keep the mesh point live - if I turn off it just kills the connection. Months ago I was experiencing decent signal level of 60 - 62 dBm, after the update it's pushing 68 - and I've got to keep it on 2.4 GHz now.

    Just wanted you to know that there's at least one other person out there who has been monitoring this and took notice.


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