cancel
Showing results for 
Search instead for 
Did you mean: 

Sync Timing Synchronization Failures

cjb110
On our wavelength

Today my internet has been immensely flakey and looking at the hub logs I'm getting tons of:

03/05/2021 17:57:39 Warning!RCS Partial Service;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;

03/05/2021 17:51:20 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx;CMTS-MAC=xxa;CM-QOS=1.1;CM-VER=3.0;

Repeated every few minutes.

 

Dunno if these Pre/Post RS errors are supposed to be this high either!

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1Locked38.92318181177646
2Locked40.3213949546148
3Locked37.3231253072945
4Locked38.91935654134487
5Locked40.317645138465
6Locked40.3174185735135
7Locked40.3165809551425

 

Rebooted the modem and the router (synology), made no impact, was fine last week, speedtest is 250mbps/34Mbs on the M350 package in the Bristol area.

2 ACCEPTED SOLUTIONS

Accepted Solutions

Can you please upload your router stats and set up a BQM

Type 192.168.0.1 or (192.168.100.1 if you have your Hub in Modem mode) into your address bar at the top of your browser

DO NOT LOG IN, just click “Check Router Status” at the bottom of the page. Sometimes the “Check Router Status” is missing, in this case just go ahead and log in and go to Advanced Settings-> Tools-> Network Status.

Please copy and paste the contents of the Downstream, Upstream, Configuration and Network Log tabs, if you get a yellow warning just click the Post button again.

You can use more than one post for each item if needed!

If you get a warning when you hit “Post” just hit “Post” again and it should work ok!

Please do not use screenshots

Also can you please setup a Broadband Quality Monitor (BQM) at thinkbroadband.com. Just click on Create a new monitor.

Under your graph you just created Click (Share Live Graph)

Copy the text in the “Direct Link” box and paste it on here

***********************************************************************************************************************************
BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
***********************************************************************************************************************************
My Broadband Ping - BT Full Fibre 900

See where this Helpful Answer was posted

Hello cjb110

I am happy to arrange an engineer to come out 

I will need to send you a private message to pass security 
If you can check the purple envelope top right of your screen that would be great 
Regards     
Gareth_L

See where this Helpful Answer was posted

9 REPLIES 9

conman33158
Super solver

Have you tried a full factory reset? Hold in the pinhole at the rear of the router for at least 50 seconds and then release (the lights will flash while holding in the pinhole reset button after about 10-15 seconds) then allow 5 minutes for the router to reboot and re-sync the connection.
Please ensure that your WiFi network password is still readable on the Hub sticker before you do this or that you at least have a copy of your original network password 🙂

***********************************************************************************************************************************
BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
***********************************************************************************************************************************
My Broadband Ping - BT Full Fibre 900

Yep tried that.

It has cleared up for now (possibly with the weather)...but it does suggest there's something wrong somewhere doesn't it? Some bad wind/rain shouldn't cause this.

Can you please upload your router stats and set up a BQM

Type 192.168.0.1 or (192.168.100.1 if you have your Hub in Modem mode) into your address bar at the top of your browser

DO NOT LOG IN, just click “Check Router Status” at the bottom of the page. Sometimes the “Check Router Status” is missing, in this case just go ahead and log in and go to Advanced Settings-> Tools-> Network Status.

Please copy and paste the contents of the Downstream, Upstream, Configuration and Network Log tabs, if you get a yellow warning just click the Post button again.

You can use more than one post for each item if needed!

If you get a warning when you hit “Post” just hit “Post” again and it should work ok!

Please do not use screenshots

Also can you please setup a Broadband Quality Monitor (BQM) at thinkbroadband.com. Just click on Create a new monitor.

Under your graph you just created Click (Share Live Graph)

Copy the text in the “Direct Link” box and paste it on here

***********************************************************************************************************************************
BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
***********************************************************************************************************************************
My Broadband Ping - BT Full Fibre 900

It does look like it was related to the bad weather yesterday (no more of those time sync log errors today), but it was just UK weather and certainly not bad enough to expect this kind of interruption of service.

BQM: bqm (updated link)

Status:

Item Status Comments

Acquired Downstream Channel (Hz)
203000000
Locked
Ranged Upstream Channel (Hz)
60300000
Locked
Provisioning State
Online

 

Downstream:

Downstream bonded channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

12030000002.239256 qam9
22110000002.540256 qam10
32190000002.538256 qam11
42270000002.238256 qam12
52350000002.740256 qam13
62430000002.240256 qam14
72510000002.240256 qam15
82590000002.740256 qam16
92670000002.440256 qam17
102750000002.540256 qam18
112830000002.740256 qam19
122910000002.540256 qam20
132990000003.740256 qam21
143070000003.240256 qam22
153150000003.240256 qam23
16323000000340256 qam24
173630000002.240256 qam25
18371000000240256 qam26
193790000001.438256 qam27
203870000001.538256 qam28
213950000001.238256 qam29
224030000000.940256 qam30
234110000001.740256 qam31
244190000001.238256 qam32



Downstream bonded channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1Locked39.32492512201269
2Locked40.3230089155539
3Locked38.6247192176852
4Locked38.92072864144646
5Locked40.319000239971
6Locked40.9187284740059
7Locked40.3177612054117
8Locked40.316252796633
9Locked40.3153855715387
10Locked40.914268894033
11Locked40.313524873287
12Locked40.312872935262
13Locked40.31186168462
14Locked40.310979531214
15Locked40.31047827510
16Locked40.3998093435
17Locked40.37682377
18Locked40.372830742
19Locked38.97174304
20Locked38.97059810
21Locked38.668040628
22Locked40.364512617
23Locked40.362253771
24Locked38.962078620

 

Upstream:

Upstream bonded channels

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID

16030000049512064 qam1
23940000047.5512064 qam4
34620000049.5512032 qam3
45370000048.3512064 qam2



Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1ATDMA0020
2ATDMA0010
3ATDMA0000
4ATDMA0000

 

 

cjb110
On our wavelength

follow on:

Configuration:

General Configuration

Network access
Allowed
Maximum Number of CPEs
1
Baseline Privacy
Enabled
DOCSIS Mode
Docsis30
Config file
cmreg-vmdg505-bbt062-b.cm



Primary Downstream Service Flow

SFID20260
Max Traffic Rate402500089
Max Traffic Burst42600
Min Traffic Rate0

 

Network Log:

Network Log

Time Priority Description

04/05/2021 00:29:29criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 23:42:20Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 22:48:19criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 21:38:48Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:47:24criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:46:30Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:45:27criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:41:33Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:35:33criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:34:50Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:28:58criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:28:24Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:28:19criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:27:17Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:26:59criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:26:3Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:25:48criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:25:38Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:25:33criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/05/2021 19:11:19Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

 

Your BQM link is not working mate. You should also maybe do a factory reset and see if the errors come back 🙂

 

***********************************************************************************************************************************
BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
***********************************************************************************************************************************
My Broadband Ping - BT Full Fibre 900

doh, fixed the bqm link. though might have to check the ICMP setting on my router.

I did one when it was occuring to no effect, don't really want to do another if I can avoid it, esp in the middle of the working day.

Your BQM looks pretty good at the minute mate, I noticed you have 1 upload stream on 32 QAM instead of 64 but this can fluctuate depending on noise on the line. How are things now after a reset? Are there still Post RS Errors building up and any T3 Time out errors?

If the issue is happening when it rains it would indicate water ingress somewhere outside and you would probably be best calling it in when it happens so they can get an engineer to look into this further.

***********************************************************************************************************************************
BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
***********************************************************************************************************************************
My Broadband Ping - BT Full Fibre 900

Hello cjb110

I am happy to arrange an engineer to come out 

I will need to send you a private message to pass security 
If you can check the purple envelope top right of your screen that would be great 
Regards     
Gareth_L