WiFi 5 breaking down every few hours/days | WRT1900ACS

johnnysl · March 21, 2020, 11:38am

I have a wrt1900ac V2, which I think is identical to the ACS? Mine is rock solid, but I build my own image.
DFS detection in the driver is broken beyond help. This is pretty well known. If you really think it is DFS, I could share you a personal build for acs to work around the the issue.

Jamesbe12 · March 21, 2020, 12:02pm

I've just tested it with 8 o'clock.
Did not work?

lede_dude · March 21, 2020, 12:19pm

Hi, cron uses 24 hour clock.

# 8 o'clock in the morning
0 8 * * * wifi   

# 8 o'clock in the evening
0 20 * * * wifi

This site will do it for you, just have a look:

https://crontab-generator.org/

And you need to restart the cron service:

System -> Startup -> cron --- select restart

on4awv · March 25, 2020, 3:27pm

Sorry for this late reply; I took my time digging into internet regarding this issue and I was surprised to note that similar issues have been reported by many other users (including this forum). I have found tickets being "solved"/closed with following very disappointing comment: never use DFS enabled channels . There have been endless discussions regarding proprietary drivers aka binary blobs and related development. In this context I found following link. Up to you to conclude.

Jamesbe12 · March 25, 2020, 6:18pm

I have the same trouble with my 1900acs even with dd wrt and open wrt....

steinmb · April 1, 2020, 11:58am

More DFS information is found in https://github.com/kaloz/mwlwifi/issues/280 it is about WRT3200 though same driver and most of the information is generic anyway. Here is also some information - https://pages.corifeus.com/github/openwrt-insomnia/docs/linksys-wrt-radar-detection.html

I have increased my system log file size and are monitoring for DFS events.

logread | grep DFS

Need more data on what causes my drop of signal though DFS real or fake events is high on my list

steinmb · April 2, 2020, 8:46pm

Here is mine log. DFS activity:

logread | grep DFS
Thu Apr  2 11:32:12 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:32:12 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:32:12 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:32:12 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:32:23 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:32:23 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:32:23 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:32:23 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:32:34 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:32:34 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:32:34 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:32:34 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:32:46 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:32:46 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:32:46 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:32:46 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:35:56 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:35:56 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:35:56 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:35:56 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:36:07 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:36:07 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:36:07 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:36:07 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:36:18 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:36:18 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:36:18 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:36:18 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:36:30 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:36:30 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:36:30 2020 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Thu Apr  2 11:36:30 2020 daemon.notice hostapd: wlan0: interface state DFS->DISABLED
Thu Apr  2 11:40:55 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:40:55 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5680 chan=136 sec_chan=-1, width=0, seg0=134, seg1=0, cac_time=60s
Thu Apr  2 11:41:59 2020 daemon.notice hostapd: wlan0: DFS-CAC-COMPLETED success=1 freq=5680 ht_enabled=1 chan_offset=-1 chan_width=2 cf1=5670 cf2=0
Thu Apr  2 11:42:00 2020 daemon.notice hostapd: wlan0: interface state DFS->ENABLED
Thu Apr  2 11:53:45 2020 daemon.warn hostapd: Failed to check if DFS is required; ret=-1
Thu Apr  2 11:53:45 2020 daemon.warn hostapd: Failed to check if DFS is required; ret=-1
Thu Apr  2 11:53:57 2020 daemon.warn hostapd: Failed to check if DFS is required; ret=-1
Thu Apr  2 11:53:57 2020 daemon.warn hostapd: Failed to check if DFS is required; ret=-1
Thu Apr  2 11:54:06 2020 daemon.notice hostapd: wlan0: interface state HT_SCAN->DFS
Thu Apr  2 11:54:06 2020 daemon.notice hostapd: wlan0: DFS-CAC-START freq=5300 chan=60 sec_chan=1, width=0, seg0=62, seg1=0, cac_time=60s
Thu Apr  2 11:55:08 2020 daemon.notice hostapd: wlan0: DFS-CAC-COMPLETED success=1 freq=5300 ht_enabled=1 chan_offset=1 chan_width=2 cf1=5310 cf2=0
Thu Apr  2 11:55:08 2020 daemon.notice hostapd: wlan0: interface state DFS->ENABLED
Thu Apr  2 12:23:00 2020 daemon.notice hostapd: wlan0: DFS-RADAR-DETECTED freq=5300 ht_enabled=1 chan_offset=1 chan_width=2 cf1=5310 cf2=0
Thu Apr  2 12:23:00 2020 daemon.notice hostapd: wlan0: DFS-NEW-CHANNEL freq=5180 chan=36 sec_chan=1
Thu Apr  2 12:53:04 2020 daemon.notice hostapd: wlan0: DFS-NOP-FINISHED freq=5300 ht_enabled=0 chan_offset=0 chan_width=0 cf1=5300 cf2=0
Thu Apr  2 12:53:04 2020 daemon.notice hostapd: wlan0: DFS-NOP-FINISHED freq=5320 ht_enabled=0 chan_offset=0 chan_width=0 cf1=5320 cf2=0

dyha · October 23, 2020, 9:03am

Hi,
I observed the same behaviour at my router (WRT190ACS).

I found, that the IP/MAC address is not got free after the DFS channel switch.

Observed behaviour:

Two devices are connected to the WiFi5
DFS channel switch
One device works correct, second device can not connect to the WiFi 5
After some time the second device is connected to the WiFi 2,4 (but with fake/new MAC address and becomes IP from the free part of IPs from DHCS)

The look in the log file says, that the MAC/IP address from the second device (which cannot re-connect) is still in use.

Write please, how to set debug log level for this issue and how to write the log file to at dedicated location (/mnt/sdaX/..., 2 GB available space, usb2.0), then I will attached the completed log file.
The standard log level does not contain useful informations about this issue.

Best Regards
dyha

dyha · October 23, 2020, 1:56pm

Hi,
I was wrong, this is not associated witch the channel switch of WiFi5.

This is something wrong with release of a IP after disconnection of a interface. This can happens after channel switch of WiFi5.

The interesting log file is below:

Fri Oct 23 08:56:50 2020 daemon.info dnsmasq-dhcp[5336]: DHCPREQUEST(br-lan) 192.168.0.154 94:de:80:af:46:d2
Fri Oct 23 08:56:50 2020 daemon.info dnsmasq-dhcp[5336]: DHCPACK(br-lan) 192.168.0.154 94:de:80:af:46:d2 KAJTU-Desktop
Fri Oct 23 09:09:49 2020 kern.debug kernel: [34346.405402] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:09:49 2020 kern.debug kernel: [34346.453698] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:09:50 2020 kern.debug kernel: [34347.230656] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:09:50 2020 kern.debug kernel: [34347.283728] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:09:50 2020 kern.debug kernel: [34347.344255] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:09:50 2020 kern.debug kernel: [34347.404475] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:10:54 2020 user.notice nft-qos-monitor: ACTION=remove, MACADDR=38:78:62:5d:21:07, IPADDR=192.168.0.150, HOSTNAME=Ewula-XPERIA
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]: Error: syntax error, unexpected handle
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]: delete handle 9
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]:        ^^^^^^
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]: Error: syntax error, unexpected handle
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]: delete handle 10
Fri Oct 23 09:10:54 2020 daemon.debug dnsmasq-script[5336]:        ^^^^^^
Fri Oct 23 09:10:54 2020 user.notice nft-qos-dynamic: ACTION=remove, MACADDR=38:78:62:5d:21:07, IPADDR=192.168.0.150, HOSTNAME=Ewula-XPERIA
Fri Oct 23 09:11:08 2020 kern.debug kernel: [34425.310646] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:20:07 2020 kern.debug kernel: [34964.206636] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:20:07 2020 kern.debug kernel: [34964.251673] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:20:07 2020 kern.debug kernel: [34964.312651] ieee80211 phy1: Mac80211 start BA 9c:5c:f9:ea:ac:a0
Fri Oct 23 09:21:20 2020 daemon.info hostapd: wlan0: STA f0:ee:10:c2:95:c2 IEEE 802.11: authenticated
Fri Oct 23 09:21:20 2020 daemon.info hostapd: wlan0: STA f0:ee:10:c2:95:c2 IEEE 802.11: associated (aid 2)
Fri Oct 23 09:21:20 2020 daemon.notice hostapd: wlan0: AP-STA-CONNECTED f0:ee:10:c2:95:c2
Fri Oct 23 09:21:20 2020 daemon.info hostapd: wlan0: STA f0:ee:10:c2:95:c2 WPA: pairwise key handshake completed (RSN)

It seems the bug is in the

daemon.debug dnsmasq-script[5336]: Error: syntax error, unexpected handle

Best Regards
dyha