Home Network Community > All Threads > Archer C9 v3 - Drops 5GHZ band, Log Errors
< All Threads

Archer C9 v3 - Drops 5GHZ band, Log Errors

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.

Archer C9 v3 - Drops 5GHZ band, Log Errors

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.
Archer C9 v3 - Drops 5GHZ band, Log Errors
Archer C9 v3 - Drops 5GHZ band, Log Errors
2021-07-06 16:06:03 - last edited 2021-07-07 18:27:49
Model: Archer C9  
Hardware Version: V3
Firmware Version: 1.3.1 Build 20171215 rel.35219

5GHZ band randomly resets and drops connection for anything connected to it. The 2.4GHZ band can be switched to and will still work. This happens at least once a day, if not more, at seemingly random times. There is no issue with the power adapter (it's the original), and I tried it on its own outlet, but that did not help, in case it were an issue.

 

(NOTE: This also happened to a v1 version of the same router for me that I could only make work by going to a previous firmware. I do not want to do that since the latest for v3 had a security fix.)

 

Is there a later beta after 2018 for this router that fixes this issue?

 

This results in this set of errors in the log (note the weird dates of 1970 and 2017):

 

Hardware Version: ArcherC9 v3.0
Software Version: 1.3.1 Build 20171215 rel.35219

2021-07-06 11:52:40 locale[14901]: <6> 283051 Language is changed to 'en_US'
2021-07-06 11:52:40 locale[14901]: <7> 283002 Explorer language is 'en_US'
2021-07-06 11:38:41 led-controller[912]: <6> 288051 Start to run WAN1_ON
2021-07-06 11:38:41 led-controller[912]: <7> 288004 WAN1_ON is found
2021-07-06 11:38:41 led-controller[912]: <7> 288003 Led rule name is WAN1_ON
2021-07-06 11:38:41 led-controller[912]: <7> 288001 Receive data length = 132
2021-07-06 11:38:41 led-controller[912]: <6> 288051 Start to run WAN0_OFF
2021-07-06 11:38:41 led-controller[912]: <7> 288004 WAN0_OFF is found
2021-07-06 11:38:41 led-controller[912]: <7> 288003 Led rule name is WAN0_OFF
2021-07-06 11:38:41 led-controller[912]: <7> 288001 Receive data length = 132
2021-07-06 11:38:41 led-controller[912]: <6> 288051 Start to run LAN_ON
2021-07-06 11:38:41 led-controller[912]: <7> 288004 LAN_ON is found
2021-07-06 11:38:41 led-controller[912]: <7> 288003 Led rule name is LAN_ON
2021-07-06 11:38:41 led-controller[912]: <7> 288001 Receive data length = 132
2021-07-06 11:38:36 locale[8077]: <6> 283051 Language is changed to 'en_US'
2021-07-06 11:38:36 locale[8077]: <7> 283002 Explorer language is 'en_US'
2021-07-06 11:38:04 locale[7714]: <6> 283051 Language is changed to 'en_US'
2021-07-06 11:38:04 locale[7714]: <7> 283002 Explorer language is 'en_US'
2021-07-06 11:38:03 locale[7653]: <6> 283051 Language is changed to 'en_US'
2021-07-06 11:38:03 locale[7653]: <7> 283002 Explorer language is 'en_US'
2021-07-06 11:37:57 led-controller[912]: <6> 288051 Start to run WAN1_ON
2021-07-06 11:37:57 led-controller[912]: <7> 288004 WAN1_ON is found
2021-07-06 11:37:57 led-controller[912]: <7> 288003 Led rule name is WAN1_ON
2021-07-06 11:37:57 led-controller[912]: <7> 288001 Receive data length = 132
2021-07-06 11:37:57 led-controller[912]: <6> 288051 Start to run WAN0_OFF
2021-07-06 11:37:57 led-controller[912]: <7> 288004 WAN0_OFF is found
2021-07-06 11:37:57 led-controller[912]: <7> 288003 Led rule name is WAN0_OFF
2021-07-06 11:37:57 led-controller[912]: <7> 288001 Receive data length = 132
2021-07-06 11:37:57 led-controller[912]: <6> 288051 Start to run LAN_ON
2021-07-06 11:37:57 led-controller[912]: <7> 288004 LAN_ON is found
2021-07-06 11:37:57 led-controller[912]: <7> 288003 Led rule name is LAN_ON
2021-07-06 11:37:57 led-controller[912]: <7> 288001 Receive data length = 132
2017-12-15 00:00:33 led-controller[912]: <6> 288051 Start to run WAN1_OFF
2017-12-15 00:00:33 led-controller[912]: <7> 288004 WAN1_OFF is found
2017-12-15 00:00:33 led-controller[912]: <7> 288003 Led rule name is WAN1_OFF
2017-12-15 00:00:33 led-controller[912]: <7> 288001 Receive data length = 132
2017-12-15 00:00:33 led-controller[912]: <6> 288051 Start to run WAN0_ON
2017-12-15 00:00:33 led-controller[912]: <7> 288004 WAN0_ON is found
2017-12-15 00:00:33 led-controller[912]: <7> 288003 Led rule name is WAN0_ON
2017-12-15 00:00:33 led-controller[912]: <7> 288001 Receive data length = 132
2017-12-15 00:00:33 led-controller[912]: <6> 288051 Start to run LAN_ON
2017-12-15 00:00:33 led-controller[912]: <7> 288004 LAN_ON is found
2017-12-15 00:00:33 led-controller[912]: <7> 288003 Led rule name is LAN_ON
2017-12-15 00:00:33 led-controller[912]: <7> 288001 Receive data length = 132
2017-12-15 00:00:29 qos[7015]: <6> 259504 Service start
2017-12-15 00:00:29 qos[7015]: <6> 259503 Function disabled
2017-12-15 00:00:19 factory-reset[5537]: <6> 284504 Service start
2017-12-15 00:00:19 parental-control[5467]: <6> 229504 Service start
2017-12-15 00:00:19 parental-control[5467]: <6> 229503 Function disabled
2017-12-15 00:00:18 access-control[5408]: <6> 239504 Service start
2017-12-15 00:00:18 access-control[5408]: <6> 239503 Function disabled
2017-12-15 00:00:17 nat[4871]: <7> 211001 Flush conntrack
2017-12-15 00:00:17 nat[4871]: <6> 211502 Function enabled
2017-12-15 00:00:17 nat[4871]: <5> 211051 Create NAT chain succeeded
2017-12-15 00:00:16 nat[4871]: <6> 211501 Initialization succeeded
2017-12-15 00:00:16 nat[4871]: <6> 211501 Initialization succeeded
2017-12-15 00:00:15 basic-security[4375]: <6> 219504 Service start
2017-12-15 00:00:15 basic-security[4375]: <5> 219606 Flush conntrack table succeeded
2017-12-15 00:00:14 firewall[1927]: <6> 209504 Service start
2017-12-15 00:00:08 imb[2782]: <6> 218507 Daemon connection succeeded
2017-12-15 00:00:08 imb[2782]: <6> 218012 ARP Binding disabled
2017-12-15 00:00:08 imb[2782]: <6> 218506 Config interface initialization succeeded
2017-12-15 00:00:08 imb[2782]: <6> 218501 Initialization succeeded
2017-12-15 00:00:07 upnp[2597]: <6> 217504 Service start
2017-12-15 00:00:07 upnp[2597]: <6> 217505 Service stop
2017-12-15 00:00:00 led-controller[916]: <6> 288051 Start to run STATUS_SAN
2017-12-15 00:00:00 led-controller[916]: <7> 288004 STATUS_SAN is found
2017-12-15 00:00:00 led-controller[916]: <7> 288003 Led rule name is STATUS_SAN
2017-12-15 00:00:00 led-controller[916]: <7> 288001 Receive data length = 132
1970-01-01 00:00:10 led-controller[916]: <6> 288504 Service start
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led WLAN5G
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led WLAN2G
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led STATUS
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led WAN2
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led WAN1
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led WPS
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led USB3
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led USB1
1970-01-01 00:00:10 led-controller[916]: <7> 288002 Adding led LAN

 

Thanks!

 

Can anyone like @Kevin_Z shed any light?

  0      
 
  0      
 
#1
Options
3 Reply
Re:Archer C9 v3 - Drops 5GHZ band, Log Errors
2021-07-12 08:34:24

@zerbrechen 

 

May I know what kind of devices failed to connect to the 5G network? Was there some specific device that lose the connection, or this happens randomly on all the devices?


When some devices lose the connection, are they far away from the router? Is the signal not good? Try to run a Wi-Fi analyzer to verify which 5G channel is clearer, then try the channel, you can also change the channel width to 40MHz, change security to WPA/WPA2-Personal, WPA2-PSK/AES, then reboot it and confirm.


Is the internet LED on the C9 always green? Who is your ISP? 

Nice to Meet You in Our TP-Link Community. Check Out the Latest Posts: Connect TP-Link Archer BE550 to Germany's DS-Lite (Dual Stack Lite) Internet via WAN Archer GE550 - BE9300 Tri-Band Wi-Fi 7 Gaming Router EasyMesh Is Available When Wi-Fi Routers Work in AP Mode as A Controller. Archer BE550 New Software Enhances System Stability and Optimizes MLO Network Stability. If you found a post or response helpful, please click Helpful (arrow pointing upward icon). If you are the author of a topic, remember to mark a helpful reply as the "Recommended Solution" (star icon) so that others can benefit from it.
  0  
  0  
#2
Options
Re:Archer C9 v3 - Drops 5GHZ band, Log Errors
2021-07-12 13:35:39

@Kevin_Z Thanks for the reply!


 

May I know what kind of devices failed to connect to the 5G network?

Any and all types of devices: laptops may stay connected to the router but show 'no internet connection', cellphone (iphone) drop the connection altogether, chromecasts drop the connection altogether

 

Was there some specific device that lose the connection, or this happens randomly on all the devices?

Nothing specific, seems it affects anything connected


When some devices lose the connection, are they far away from the router? Is the signal not good?

Signal is good in every room that access the router, this can happen on a device connected in the same room as the router, does not make a difference

 

 

Try to run a Wi-Fi analyzer to verify which 5G channel is clearer, then try the channel, you can also change the channel width to 40MHz, change security to WPA/WPA2-Personal, WPA2-PSK/AES, then reboot it and confirm.

I've changed channels and it makes no difference, but I guess I can try changing the width; security was already on those as well - no difference.


Is the internet LED on the C9 always green? Who is your ISP? 

The LEDs stay normal (no orange light); ISP is Verizon FIOS in the US

 

Thanks for any more help with this!

  0  
  0  
#3
Options
Re:Archer C9 v3 - Drops 5GHZ band, Log Errors
2021-07-13 01:12:31

@zerbrechen 

 

Thank you very much for all the details. To locate this issue and try to fix it, we would like to follow up on your case via email. Please check your inbox and provide the information that we need.

Nice to Meet You in Our TP-Link Community. Check Out the Latest Posts: Connect TP-Link Archer BE550 to Germany's DS-Lite (Dual Stack Lite) Internet via WAN Archer GE550 - BE9300 Tri-Band Wi-Fi 7 Gaming Router EasyMesh Is Available When Wi-Fi Routers Work in AP Mode as A Controller. Archer BE550 New Software Enhances System Stability and Optimizes MLO Network Stability. If you found a post or response helpful, please click Helpful (arrow pointing upward icon). If you are the author of a topic, remember to mark a helpful reply as the "Recommended Solution" (star icon) so that others can benefit from it.
  1  
  1  
#4
Options

Information

Helpful: 0

Views: 775

Replies: 3

Related Articles
ARCHER C9 - LOG
537 0
Archer C9 drops connection regularly
1997 0
C9 System Log
264 0
Archer C9 v3 firmware release
2063 0
Archer C9 Drops Internet Connection to ISP
443 0
Online up date, Archer C9 AC1900 Wireless Dual Band Gigabit Router
1168 0
About Us
Press
Copyright © TP-Link Systems Inc. All rights reserved.