Issues after 2.4.0 upgrade - A5-14

Our system was working pretty well and then we upgraded 2 AP’s to 2.4.0. Now we are having all sorts of little issues.

We were working in a 20 MHz band and the PER on a few clients (less than a block away with clear LOS) was high. We increased the power on the A5 and changed to 40 MHz. The PER is now much better, but we have had various things that are strange.

On one AP, we had to power cycle the client 3 or 4 times in order to get a connection and IP address from the router. I think 2.4.0 may have introduced an issue that seemed to have been fixed in 2.3.0. Nothing has physically changed in our network and we may be having DHCP issues again. We use Mikrotik routers to hand out DHCP at each tower.

I’d be curious if anyone else is seeing anything strange with the new 2.4.0 firmware. It’s not consistent, so could be a client router or something else. I know there do not seem to be issues with a G2 behind the C5.



I upgraded 4 A5c’s to the 2.4.0 firmware and its pretty much been smooth sailing. I don’t use SRS so maybe that helps. The only problem i’ve had is I went to save the CPE Data port VLAN and it wouldn’t save. I needed to reboot the AP (yes other customers didn’t like it) then it allowed me to save.

There is one other issue, but not sure its related to the firmware version. One of the A5c’s has decided the GPS signal is ‘bad’. Even through it’s 110mtrs above ground level of the surrounding town and can see the sky pretty well :slight_smile:

No DHCP problems once the VLAN’s were saved though.

We downgraded 2 APs to 2.3.3 and the problems went away. We had one customer in particular that had their C5 connected, but could not pass traffic. We had them connect directly to the PoE and also provided them with tested routers all with no luck. At the 2nd site, they also had no connectivity but after the downgrade, everything worked with nothing else changing.

We are not running VLANs in our setup but do run DHCP from the MIkrotik behind the A5.

For GPS, we have 19 satellites all with -45 or better. This is on 2.3.3, but I know I checked on 2.4 as soon as it rebooted and things seemed fine (the dashboard said good). We checked because we had a failure early on with an A5-18 after upgrade. Same scenario that you described. That unit ultimately needed to be replaced.

One thing you really need to check if you haven’t done so is how the mimosa has changed the SSID Settings.

There is no longer a VLAN Passthrough option. You need to change you Radio to Trunk Mode in the SSID settings. without this it will not pass any VLAN Traffic. Trunk does just what it implies. It works as a switching trunk port.

When we first upgrade to 2.4 we had the same problem your describing until we read the docs and realized we needed to change the mode from Fixed CP or Hotspot to Trunk. after we did that we have seen enormous performance and stability improvements. especially in WIFI Interop.

Just finished upgrading to 2.4.0.

Cloud FW upgrade went through swimmingly. All associations came back. Upgrade process was flawless this go around as compared to previous FW upgrades.

Will watch performance.

Running in SRS mode.


I have had very similar issues myself. I am not sure if they directly coincide with the 2.4 rollout or not, but it seems that our PER and data rates totally went to ■■■■. It was blamed on noise, but I don’t think my noise levels have increased that much.

We also saw performance issues as a result of upgrading to 2.4. PER rose and throughput dropped operating in SRS mode.

GPS signal did intermittently report as “Bad” from the dashboard.

Have rolled back to 2.3.3 for the time being and everything has stabilised for the most part. Im not 100% that the rise in PER was as a direct result of the 2.4 upgrades as this was isolated to a few sites, however the “Bad” GPS signal is concerning.

Does anyone have an update on the “Bad GPS” Issue? We have been hunting something that sounds like this for months in our A5s with the Mimosa Help Desk guys and we have found nothing that has helped, I was hoping the 2.4.0 Firmware might have the key, but no dice…

William, Bad GPS is either a blocked line of site or interference with either LTE or FM broadcast transmitters. We do suggest running either 2.3.3 or the newly available pre-release of However while these two firmware builds have a number of improvements and fixes; they probably won’t impact the availability of the GPS signal. I did check the A5c that you reported GPS problems with, all show good GPS signal except for one which is not connected to the Mimosa Cloud at this time. But it also showed good GPS signal the last time it was connected to the Mimosa Cloud. If you are still having GPS or any other problems, please reengage with our Support team.

Thanks DavidD, Ya, I know, your support has made that very clear to me. But the issue is not consistent and as I told the support guys (Call out for my guys Ibrahim and Ahmet, some of the best support I have ever received, give those guys a raise) We have clear LOS and not another tower of any significance for miles. So I have to wait for my boss to have time to climb the tower and swap radios to see what we can see. We have the problem mitigated, for now, but I was hopeful someone else was smarter then me and had found something I have missed for months…

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