Crazy high TX error rates

Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Broadcom SoC based Hardware
Author Message
roger.knobbe
DD-WRT Novice


Joined: 12 Oct 2020
Posts: 5

PostPosted: Tue Oct 13, 2020 16:14    Post subject: Crazy high TX error rates Reply with quote
I've got Firmware: DD-WRT v3.0-r44483 std (10/02/20) running on 2 Netgear boxes, one r7000p, and one r6400v2. I'm seeing REALLY high eth TX error rates on both. Where should I look first to diagnose this?

Both boxes have been up for about 3 days, and have the following error counts in ifconfig:

Code:

root@r7000p:~# ifconfig
...
eth1      Link encap:Ethernet  HWaddr CC:40:D0:FC:FF:EB
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:6467330 errors:0 dropped:192 overruns:0 frame:6553611
          TX packets:18102521 errors:8338638 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:3307752212 (3.0 GiB)  TX bytes:2868682903 (2.6 GiB)
          Interrupt:163

eth2      Link encap:Ethernet  HWaddr CC:40:D0:FC:FF:FC
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:8879174 errors:0 dropped:241 overruns:0 frame:0
          TX packets:28474442 errors:0 dropped:4360945 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2088051706 (1.9 GiB)  TX bytes:2411759896 (2.2 GiB)


Code:

root@R6400v2:~# ifconfig
...
eth1      Link encap:Ethernet  HWaddr 9C:3D:CF:1E:AE:73
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:10172253 errors:0 dropped:942 overruns:0 frame:1511235
          TX packets:10135778 errors:6400801 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:295514007 (281.8 MiB)  TX bytes:1312352401 (1.2 GiB)
          Interrupt:163

eth2      Link encap:Ethernet  HWaddr 9C:3D:CF:1E:AE:84
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3597403 errors:0 dropped:368 overruns:0 frame:17192
          TX packets:16502840 errors:2474739 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2905539360 (2.7 GiB)  TX bytes:3751549221 (3.4 GiB)
          Interrupt:169


Last edited by roger.knobbe on Tue Oct 13, 2020 16:39; edited 1 time in total
Sponsor
roger.knobbe
DD-WRT Novice


Joined: 12 Oct 2020
Posts: 5

PostPosted: Tue Oct 13, 2020 16:21    Post subject: Reply with quote
More details:

Both are running as APs inside my home network, WAN connection "Disabled", WAN port assigned to switch, DHCP servers disabled, Operating mode "Router".

r6400v2 has only one LAN connection, in port 2, connected to an upstream gig switch.

r7000p has ports W, 1, 2, 3 connected. 4 is down. All ports are assigned to the LAN bridge.

Wifi is enabled on both, although I currently have turned off wl0 on r6400v2 trying to troubleshoot this problem.

My network is flat. Everything is in 192.168.1.0/24
Wildlion
DD-WRT Guru


Joined: 24 May 2016
Posts: 1084

PostPosted: Tue Oct 13, 2020 22:50    Post subject: Reply with quote
something is not right with that.

I think that we need more information though.

How is everything connected? Are those the wireless interfaces?

Have you tried new cables to connect?

I would try things like wireshark to monitor connections from clients.
roger.knobbe
DD-WRT Novice


Joined: 12 Oct 2020
Posts: 5

PostPosted: Tue Oct 13, 2020 23:50    Post subject: Reply with quote
r6400v2 is simple, single store-bought cat 5e cable to linksys gigabit switch, then upstream to larger gigabit switch, then upstream to cable modem. total cable distance from r6400v2 port 2 through 2 switches to cable modem is about 50 feet.

r7000p is more of a workhorse but same basic setup. Handmade cable from r7000p port (can't recall which one) to wall jack up through attic to larger gigabit switch, then upstream to cable modem. Similar overall cable length.

I don't know how to map from physical ports to eth1, eth2 ports. I'd appreciate some help. However, based on where the error counts show up in the web UI, those errors are coming from the wifi side not the ethernet side.

current r6400v2 after upgrading to DD-WRT v3.0-r44538 std (10/13/20) and running for just a few minutes is


Wireless Packet Info (wl0)
Received (RX)3260 OK, no error
Transmitted (TX)11299 OK, 12369 errors

Wireless Packet Info (wl1)
Received (RX)5082 OK, 12 errors
Transmitted (TX) 34203 OK, 3608 errors


Code:


clients
MAC Address   Radioname   Interface   Uptime   TX Rate   RX Rate   Info   Signal   Noise   SNR   Signal Quality
B8:27:EB:CC:D4:C0      wl0   0:09:41   72M   65M   HT20SGI   -52   -90   38   96%
F0:D5:BF:01:3B:F0      wl1   0:11:38   400M   400M   VHT80SGI   -53   -92   39   94%


AfterShock
DD-WRT User


Joined: 17 May 2010
Posts: 128

PostPosted: Wed Oct 14, 2020 2:53    Post subject: Reply with quote
I've always had high tx errors on wl0 which only seems to happen when using my laptop with an intel adapter, in total I have 21 devices connected through wifi and as long as the laptop isn't connected the tx errors stay between 3-15. what is your percentage bar reading? Mine is 100% with the worst i've seen being 99%
egc
DD-WRT Guru


Joined: 18 Mar 2014
Posts: 7693
Location: Netherlands

PostPosted: Wed Oct 14, 2020 7:09    Post subject: Reply with quote
The routers must be on separate channels and channels must be far apart.
Search for free channels with Wifi Analyzer on your phone

Also do not use 40 MHz band with.
Do not increase transmit power above defaults
Do not use Turbo QAM.

See the wireless DDWRT wiki

_________________
Routers:Netgear R7800, R6400v1, R6400v2, Linksys EA8500, EA6900 (XvortexCFE), E2000 (converted WRT320N), WRT54GS v1.
WireGuard Documents & Guides:https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=327397
OpenVPN Documents & Guides: https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=327398
IPSET: https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=327261
Install guide R6400v2:http://forum.dd-wrt.com/phpBB2/viewtopic.php?t=316399
Install guide R7800: https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=320614
Forum Guide Lines (important read):https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=324087
roger.knobbe
DD-WRT Novice


Joined: 12 Oct 2020
Posts: 5

PostPosted: Wed Oct 14, 2020 16:10    Post subject: Reply with quote
egc wrote:
The routers must be on separate channels and channels must be far apart.

Copy. r7000p is on 11+9 and r6400v2 is on channel 1

egc wrote:

Search for free channels with Wifi Analyzer on your phone

I'm in a pretty congested suburban environment, and 1/11 are about as good as any.

egc wrote:


Also do not use 40 MHz band with.

Copy. I'm using 20Mhz on both routers

egc wrote:

Do not increase transmit power above defaults

Copy. I'm using "Auto" TX power

egc wrote:

Do not use Turbo QAM.

Thanks, I disabled on the r7000p. No impact.

egc wrote:

See the wireless DDWRT wiki


Thanks, I'm setting some of the other recommendations, eg decreasing beacon interval, setting ACK timing to 0.

However, I'm still seeing right around 50% of my TX packets resulting in errors on r6400v2 wl0. 67% OK on r7000p wl0
roger.knobbe
DD-WRT Novice


Joined: 12 Oct 2020
Posts: 5

PostPosted: Thu Oct 15, 2020 14:00    Post subject: kernel.log for anyone interested Reply with quote
I'm seeing "INFO: rcu_sched self-detected stall on CPU" and stack traces in the kernel.log of r6400v2. I've posted https://0x0.st/iGkd.log here in case somebody wants to take a look.
Display posts from previous:    Page 1 of 1
Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Broadcom SoC based Hardware All times are GMT

Navigation

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum