Users needed to test Wi-Fi stability on Linksys WRT3200ACM & WRT32X on OpenWrt 21.02

A post was split to a new topic: WRT1900AC DHCP settings

Hey there.
I have this trouble of intermittent wifi cutouts on my iPhone when on my wrt3200acm.

My actual version is:
OpenWrt 21.02.1 r16325-88151b8303

When I upgrade, I don’t keep settings but I keep a list of packages installed with opkg save and restore, hotplug, etc.

I wonder if this way of preserving packages will move the problem back to my new installation.

Can I just downgrade the packages instead of upgrading the whole thing. And should I put a hold on those package version so they are not upgraded later ?

Losing every settings is a pain :slight_smile: I have wireguard, a lot of firewall customisations, etc. and I would prefer if I can just downgrade the packages instead.

Hello all, I've started bisecting OpenWRT to find the issue with DFS. I'm only getting started, but my results so far:

I started with ea91ebedce8051e4a3bf84586b589e918d1fc08c (mac80211: fix regression in SSN handling of addba tx) cherry-picked on top of ed2015c38617ed6624471e77f27fbb0c58c8c660 (mac80211: Update to version 5.8-rc2-1). 5 GHz was stable but DFS did cause issues with iPhones and others. There also may be a second bug here - my Roku was unable to find the network at all, and had previously worked fine. I will be testing that one later.

Next, I tried 600416d5c14663faa3e2eb42ff71a41d4fa8e0f6, which is the commit immediately before the ones before where mac80211 was updated. There was no cherry-pick here as it was not relevant. I started here instead of a proper bisect in order to get firm start and end points for the bisection. I did find issues with 5 GHz DFS on this branch. The Roku issue was not present.

I am currently trying the release 19.07.8 to get a lower bound on git revisions. I don't think DFS was an issue in 19.07 but I'm just covering my bases.

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Excellent. I appreciate the work that you are doing and it’s great to see people still digging into issues related to the wifi on these devices.

I have been conducting a 30+ day study related to the wifi as well. Although not specifically DFS. My testing has been related to the crashing of the 5 GHz radio and thorough testing of specific channels, transmit power, etc.

I have been successful in solving the issue of the 5 GHz radio crashing on my own WRT3200. But I still have a few more days of testing before I am ready to present my findings here.

I have 16 days of uptime now without a single 5 GHz radio crash. I wouldn’t be surprised if these other underlying wifi issues with mwlwifi could also be related to the issues you have with DFS.

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I have been successful in solving the issue of the 5 GHz radio crashing on my own WRT3200

Do you have anything new to share? Or is this the bugfix that was committed to master earlier on?

Honestly, the fix for almost all mwlwifi 5 GHz radio issues is to use channel 36. Channel 36 and life is golden.

All of my 5 GHz radio crashes (that required reboot) we’re on higher channels such as 149 which I had used for years.

The closed source firmware blob enforces TX Power regardless of what LuCI shows in the UI. The higher channels use 30, while the lower channels use 23, as far as I know.

I even tried channel 149 with TX Power manually set to 23 in LuCI. It still caused a 5 GHz radio crash.

But the question still remains, what could be causing the crash?

It has happened before with mwlwifi and previous releases of OpenWrt. However, with 21.02.x releases, it seems to trigger the crash much more frequently. I had experienced the crash every 2-3 days.

Except… on channel 36.

I am on 16 days uptime now with channel 36 and also did another 12 days or so earlier in testing also with no crash.

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I always use it on channel 36 but recently it's got very unstable. Only reducing "Width" to 40 MHz seems to have helped in my case. Wi-Fi speed is slower because of this (~150mbps) but at least it's stable.

P.S. I just did a quick speedtest and I was able to see 300mbps, FYI.

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Good afternoon, I have installed the version OpenWrt 21.02-SNAPSHOT r16473-1472a8fa42 on my linksys wrt1900ac V1, and everything works perfectly, the wifi stability problems disappeared.

Maybe I did something wrong but wrt32x, snapshot r18614-46ce629fe0 (sysupgrade from v1) and Wi-Fi is still unstable, not assigning ip on 5GhZ, disconnecting and all that trouble. Sorry for such report

The snapshots from 21.02 are here:
https://downloads.openwrt.org/releases/21.02-SNAPSHOT/targets/mvebu/cortexa9

Search and install from scratch the version for your router you will not have such problems anymore

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Thanks for the hint, will try tomorrow

Bummer... I have 4 of these, so using 36 is only an option on 1.

Channel 149 works perfectly fine here for weeks, cannot comment on longer since it isn't running longer than that. I never really had issues on 5Ghz, only on 2,4Ghz. This on a WRT32X

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I'm on a 1900acs (v2) and this is killing me as of late. Wifi drops every 30 minutes or so and comes back. Hoping 21.02.2 comes out soon as I am not wanting to risk installing a snapshot build.

EDIT: I'm going to try the 36 channel and see if it helps.

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The 21.02.2 will be released from the same 21.02 branch as the daily 21.02 snapshots are built. The stable branch rarely gets commits, so its nature is quite different from the development master.

Trying the 21.02 snapshot is rather small risk in a dual firmware router...

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I took your advice and installed the latest snapshot about an hour ago. I'll keep an eye on the network over the next few days and report back.

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Well, my 2.4GHz problems kept on going. Some devices had no issues, while a few did have issues.

One really concrete issue, a strange one but consistent, my Harmony Hubs wouldn't connect when on channel 11, but it worked on channel 1. Though my solar panel wireless adapter was the other way around.

I now installed 19.07.8 and no issues of the sort. So there still are issues with the latest snapshots.

19.07.8 is still being maintained in regards to security issues isn't it? Or are there any other real important reasons not to stay on that version? I don't mind not going to 21.02 if there are no real issues.

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Following up: I had post-radar detected disconnects on release builds of 19.07.8 and 18.06.9. So it seems this issue's been lurking around a while. I don't know why I didn't run into it before. Maybe I wasn't using DFS channels as aggressively, maybe it is something newly exposed by driver changes to the non-router hardware.

With a lack of upstream support, especially on the binary blob half of the driver, it seems like this isn't getting a fix and should just get a documented workaround - is there anyone with Wiki credentials willing to throw a note in on the wrt3200acm page?

The issue with the Roku was either ephemeral or fixed by the time of the 21.02 branch.

So my final conclusion here is to agree with Mr. Design:

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I don't know if there will be further service releases for 19.07.x or not, but you could ask in the following thread if no one answers here: OpenWrt 19.07.8 service release - #40 by Saidiadude1

I've been using my WRT32X's 5GHz on channel 149 since your comment. It's stable for me too.

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