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AF-5XHD - TX modulation stuck low until reboot?

I have a link running 1.1.2 and I just now noticed that sometime around March 8th the link suddenly went from a fairly steady 8X TX rate to a fixed 6X rate.

 

When I logged into the Master/Slave they both had an alert for "interference" that was hurting the link.  I checked Airview on both sides and based on my Airview scans and my Signal+CINR I could not find any interference.

 

Well I had to reboot the slave due to an SNMP bug and after the reboot the Slave went back to a solid 8X and the GUI no longer reported any performance alerts of interference.

 

Could they have been a brief spurt of interference on March 8th that after it was gone the link did not properly recover from and go back to the proper TX rates?

 

Capture.PNGSlave Stats - Dropped to 6X

 

 

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Re: AF-5XHD - TX modulation stuck low until reboot?


@sbyrd wrote:

I have a link running 1.1.2 and I just now noticed that sometime around March 8th the link suddenly went from a fairly steady 8X TX rate to a fixed 6X rate.

 

When I logged into the Master/Slave they both had an alert for "interference" that was hurting the link.  I checked Airview on both sides and based on my Airview scans and my Signal+CINR I could not find any interference.

 

Well I had to reboot the slave due to an SNMP bug and after the reboot the Slave went back to a solid 8X and the GUI no longer reported any performance alerts of interference.

 

Could they have been a brief spurt of interference on March 8th that after it was gone the link did not properly recover from and go back to the proper TX rates?

 

Capture.PNGSlave Stats - Dropped to 6X

 

 


@sbyrd so far I wasn't able to reproduce it. Was this link mostly idling or it has some load all the time? I guess the sup file I received for SNMP issue is the same. right?

 

-Edmundas

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Re: AF-5XHD - TX modulation stuck low until reboot?


@UBNT-Edmundas wrote:

 


@sbyrd so far I wasn't able to reproduce it. Was this link mostly idling or it has some load all the time? I guess the sup file I received for SNMP issue is the same. right?

 

-Edmundas


This link as not idle.  The Slave received around 200Mbps at peak hours and 10-12Mbps sent.  Yes you are correct the support file for the SNMP issue is the same.

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Re: AF-5XHD - TX modulation stuck low until reboot?

[ Edited ]

@UBNT-EdmundasI've got a v1.1.2 link that dropped to a low TX rate for no reason as well after several weeks of uptime. Just chaning the value of Max TX Rate on the MASTER caused it to jump right back up again.

 

speedchange3.png

 

speedchange4.png

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Re: AF-5XHD - TX modulation stuck low until reboot?

I've had a similar thing happen twice on a link. I didn't try changing any of the radio settings, I just rebooted one end of the link and the modulation was restored. (both ends are running v1.1.2.

 

AF-5XHD-demodulation.png

 

This is a backup link for a AF-24 link so normally it has no traffic. Unfortunately, the link is a bit too far to use DFS for a quieter frequency.  And while things are a tad noisy at the far end, overall I think the link is in pretty good shape. 

 

AF-5XHD-dashboard.png

 

My biggest concern is knowing when the link demodulates so I can give it a kick...

 

 

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Re: AF-5XHD - TX modulation stuck low until reboot?

So far it looks like TX Rate drops after about 50days uptime... Found couple links which dropped yesterday and developers are investigating.

 

-Edmundas

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Re: AF-5XHD - TX modulation stuck low until reboot?

We have 3 AF-5XHD links and this has only happened to one of them. All of the links are running v1.1.2.

 

The only link this has happened to is the one that is a backup and normally does not carry traffic.

 

After the first demodulation event, we rebooted the slave on Dec 17. It demodulated again on Mar 5.

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Re: AF-5XHD - TX modulation stuck low until reboot?

@UBNT-Edmundas  I just noticed another 5XHD Slave doing the same thing.  This Slave is set to 6X max and suddenly early this morning the slave TX rate dropped to 4X and the Slave GUI is reporting issues.  I suspect a reboot of th slave (scheduled for 3am tomorrow) will fix it.

 

Capture.PNG

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Re: AF-5XHD - TX modulation stuck low until reboot?

@sbyrd looks like it's the issue with rate drop after 50days uptime we have figured out and fix is coming in v1.3.0-Beta3 release.

 

-Edmundas

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Re: AF-5XHD - TX modulation stuck low until reboot?

@UBNT-Edmundas Is this specific to 50 days? I have had similar issues with a link of mine that drops after a long period of time, but its always fixed one i "reconnect" them. I don't even have to fully reboot it.

I also confirm interference by using the airviews on both sides and compare them to my initial airviews when setting up the link. Very low noise levels.
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Re: AF-5XHD - TX modulation stuck low until reboot?


@JPenner wrote:
@UBNT-Edmundas Is this specific to 50 days? I have had similar issues with a link of mine that drops after a long period of time, but its always fixed one i "reconnect" them. I don't even have to fully reboot it.

I also confirm interference by using the airviews on both sides and compare them to my initial airviews when setting up the link. Very low noise levels.

Yes. It's specific to 49days+ uptime. Reconnect is enough to fix it. v1.3.0-BETA3 will include fix and planning to release it to BETA forum early next week.

 

-Edmundas

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Re: AF-5XHD - TX modulation stuck low until reboot?

Also fixable without causing a link outage by changing the maximum modulation from 10x to 12x or any different value and then back again.

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Re: AF-5XHD - TX modulation stuck low until reboot?

Thanks! This is really good to know Man Happy
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Registered: ‎04-17-2018

Re: AF-5XHD - TX modulation stuck low until reboot?

Oh really? So far i have had to drop the link. I'll try it next time. Thanks for the info!
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Re: AF-5XHD - TX modulation stuck low until reboot?

We have seen this issue on 1.1.1 as well, I can confirm that changing just the max modulation without any reboot indeed fixes the issue. No need for reboot, nor for changing the auto modulation to fixed.

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Re: AF-5XHD - TX modulation stuck low until reboot?

This is really good to know! Thank you very much!