intermittent dropped connection takes forever to restore

[millsley]

Hello all,

Hope you can help me out, until recently we have had no problems in 5+ years. Two weeks ago we started getting connection issues, several times a day the connection would drop out, we restarted the superhub and the connection would reset, down time ~15-20 minutes in total. We called and complained about these and 2 days ago an engineer called, he said that some of the wiring was very old and replaced all the internal wires and exchanged the suberhub for a new one.  Unfortunately this has made the issue much worse, the last two days we have in total lost internet for several hours.

Now when our connection drops out restarting the hub takes 30-40 minutes for the connection to return. Here is a selection of the network log, it was working away in the same cycle from 13:19 - 13:57;

14/10/2021 13:20	critical	REG RSP not received;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:20	Error	T6 Timeout and retries exceeded;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:20	critical	Registration RSP rejected unspecified reason;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:20	critical	Registration RSP rejected message syntax error;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:20	critical	No Ranging Response received - T3 time-out;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:19	critical	REG RSP not received;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:19	Error	T6 Timeout and retries exceeded;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:19	critical	Registration RSP rejected unspecified reason;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:19	critical	Registration RSP rejected message syntax error;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 13:19	critical	No Ranging Response received - T3 time-out;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;

The first day I called 150 when this issue was ongoing and a nice lady walked me through a hard reset and got the router connected in about 25 minutes. Today I left it and took my wife to work - so she can actually do her job. I called after returning, the connection was back up and so "no issue was found" with our connection, there is an unstable connection warning in the area, but our issue seems to me to be more than that.

There is clearly something wrong with the router/cabinet handshake, here are the up/down logs from the suberhub, down;

Channel	Frequency (Hz)	Power (dBmV)	SNR (dB)	Modulation	Channel ID
1	1.39E+08	0.2	40	256 qam	1
2	1.47E+08	0.2	40	256 qam	2
3	1.55E+08	0	40	256 qam	3
4	1.63E+08	0.4	40	256 qam	4
5	1.71E+08	0.2	40	256 qam	5
6	1.79E+08	0.5	40	256 qam	6
7	1.87E+08	0.4	40	256 qam	7
8	1.95E+08	0.5	40	256 qam	8
9	2.03E+08	0.4	40	256 qam	9
10	2.11E+08	0.2	40	256 qam	10
11	2.19E+08	0.4	40	256 qam	11
12	2.27E+08	0	40	256 qam	12
13	2.35E+08	0.2	40	256 qam	13
14	2.43E+08	0.4	40	256 qam	14
15	2.51E+08	0.9	40	256 qam	15
16	2.59E+08	1.2	40	256 qam	16
17	2.67E+08	1.4	40	256 qam	17
18	2.75E+08	1.5	40	256 qam	18
19	2.83E+08	1.4	40	256 qam	19
20	2.91E+08	1.7	40	256 qam	20
21	2.99E+08	1.9	40	256 qam	21
22	3.07E+08	1.4	40	256 qam	22
23	3.15E+08	2	40	256 qam	23
24	3.23E+08	1.7	40	256 qam	24
Downstream bonded channels
Channel	Locked Status	RxMER (dB)	Pre RS Errors	Post RS Errors
1	Locked	40.9	241805	50179
2	Locked	40.9	158665	8332
3	Locked	40.3	673253	124558
4	Locked	40.3	1012660	301633
5	Locked	40.3	143858	3683
6	Locked	40.9	50152	169
7	Locked	40.3	50962	181
8	Locked	40.3	45304	195
9	Locked	40.9	29728	42
10	Locked	40.3	40436	177
11	Locked	40.3	26383	0
12	Locked	40.9	34778	112
13	Locked	40.9	18825	8
14	Locked	40.9	15973	4
15	Locked	40.3	15541	4
16	Locked	40.3	6449	0
17	Locked	40.3	45076	70
18	Locked	40.9	11894	0
19	Locked	40.9	4578	0
20	Locked	40.3	2589	0
21	Locked	40.9	1130	0
22	Locked	40.3	2129	24
23	Locked	40.3	472	0
24	Locked	40.3	1172	0

and up;

Upstream bonded channels
Channel	Frequency (Hz)	Power (dBmV)	Symbol Rate (ksps)	Modulation	Channel ID
1	46200000	51	5120	32 qam	2
2	53700000	51	5120	64 qam	1
3	32599932	51	5120	64 qam	4
4	39400000	51	5120	64 qam	3
Upstream bonded channels
Channel	Channel Type	T1 Timeouts	T2 Timeouts	T3 Timeouts	T4 Timeouts
1	ATDMA	0	0	1	0
2	ATDMA	0	0	0	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0

I hope someone can help out with whatever issues we have, we can't work from home with unreliable broadband. I've also setup a BQM if it is in any way helpful.

Thanks in advance,

Matt

[jbrennand]

Thats a bad connection - RS error counts way too high, Up power levels high and 1 channel has dropped to 32 qam. May need the tech back - but can you do this first to check.

Check if there is actually a fault by trying the “check service,” Area status webpage" (link at top right of this forum), also try the “free & automated” Service Status number - 0800 561 0061 - which usually gives the most up to date info. and tells you of more local issues down to postcode level.

If nothing shows - do the reset again but do it this way....
_________________

Do a Hub “pinhole reset” - make sure the 2 passwords on the Hub sticker are still there and legible first ! Disconnect any ethernet cables from the Hub (leave the coax connected), and then with the Hub still "switched on" throughout, press pin in firmly with paper clip/SIM tray tool or similar "thin thing" and hold it firmly for at least 60 seconds, release the pin, leave for 5’ to stabilise - dont manually switch it off at any time. See if that sorts it.
__________________________

Also set up a BQM

If you haven’t already, set up a free, secure and “offlsite” - “Broadband Quality Monitor” to continually monitor the state of your connection and record any true network dropouts , latency issues, packet drops, etc - it will thus allow you to differentiate between those and simple wifi dropouts. It does it 24/7/365 and it keeps a visual record of any/all of your network disconnections, useful data to have to match to the Network logs (in your Hub settings) and also in discussions with VM - note it will take a few hours to start seeing a sensible picture - post up the “link” to the “share live graph”. Click the lower link (Share Live Graph) then click generate. Copy the text in the Direct Link box, beware, there may be more text than you can see. On here click the Link icon (2 links chain to the left of the camera icon) In the URL box paste the link you copied and then click OK

https://www.thinkbroadband.com/broadband/monitoring/quality

[millsley]

John, many thanks for your help. 

There was and is no fault on any of the service checkers, online or on the phone. So it seems everything should be working as normal. 

I sorted a BQM and hard reset the superhub as you suggested and have waited nearly 24 hours to see the effects.

the BQM link is here, https://www.thinkbroadband.com/broadband/monitoring/quality/share/dd66c08f749e5d61898ace47587a9c4067... you can see where I hard reset at about 19:30. 

The superhub logs are similar, but perhaps you can see something in them i can't; 

down-

Channel	Frequency (Hz)	Power (dBmV)	SNR (dB)	Modulation	Channel ID
1	138750000	0.9	40	256 qam	1
2	146750000	0.7	40	256 qam	2
3	154750000	0.7	40	256 qam	3
4	162750000	1	40	256 qam	4
5	170750000	0.9	40	256 qam	5
6	178750000	1	40	256 qam	6
7	186750000	0.9	40	256 qam	7
8	194750000	1	40	256 qam	8
9	202750000	0.9	40	256 qam	9
10	210750000	0.7	40	256 qam	10
11	218750000	0.7	40	256 qam	11
12	226750000	0.5	40	256 qam	12
13	234750000	0.7	40	256 qam	13
14	242750000	0.9	40	256 qam	14
15	250750000	1.4	40	256 qam	15
16	258750000	1.7	40	256 qam	16
17	266750000	1.9	40	256 qam	17
18	274750000	2	40	256 qam	18
19	282750000	2	40	256 qam	19
20	290750000	2.2	40	256 qam	20
21	298750000	2.2	40	256 qam	21
22	306750000	1.7	40	256 qam	22
23	314750000	2.5	40	256 qam	23
24	322750000	2	40	256 qam	24
Downstream bonded channels
Channel	Locked Status	RxMER (dB)	Pre RS Errors	Post RS Errors
1	Locked	40.9	97843	7982
2	Locked	40.9	9111	441
3	Locked	40.9	61451	6865
4	Locked	40.9	129885	18396
5	Locked	40.3	9421	357
6	Locked	40.3	1092	172
7	Locked	40.9	1829	88
8	Locked	40.9	9026	218
9	Locked	40.3	2613	70
10	Locked	40.3	7215	184
11	Locked	40.3	6060	116
12	Locked	40.3	4245	98
13	Locked	40.3	1962	101
14	Locked	40.9	403	68
15	Locked	40.3	240	102
16	Locked	40.9	1992	44
17	Locked	40.3	7766	201
18	Locked	40.9	4155	35
19	Locked	40.9	121	29
20	Locked	40.9	80	60
21	Locked	40.9	47	18
22	Locked	40.9	49	33
23	Locked	40.3	116	18
24	Locked	40.3	1043	36

Up -  

Channel	Frequency (Hz)	Power (dBmV)	Symbol Rate (ksps)	Modulation	Channel ID
1	46200000	51	5120	64 qam	2
2	53700000	51	5120	64 qam	1
3	32600000	51	5120	64 qam	4
4	39400000	51	5120	64 qam	3
Upstream bonded channels
Channel	Channel Type	T1 Timeouts	T2 Timeouts	T3 Timeouts	T4 Timeouts
1	ATDMA	0	0	2	0
2	ATDMA	0	0	0	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0

and the network log shows the dropout at 21:30 that we also can see in the BQM - it didn't log the high latency/drop just before 20:00  or any of the later peaks.

14/10/2021 21:33	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;
14/10/2021 21:32	Warning!	RCS Partial Service;CM-MAC=**;CMTS-MAC=**;CM-QOS=1.1;CM-VER=3.0;

Any further advice would be great, perhaps there is something else i can do this end? 

Many thanks again,

Matt

[John_GS]

Hi millsley

Thanks for posting - it needs a tech visit as the upstream is higher than should be.

I'll send you a PM to assist further.

Kind regards,

[millsley]

responded.

Thanks.

M

[John_GS]

Hi @millsley

Thanks for joining me on PM - just to confirm for the thread, the engineer visit has been booked in.

This can be tracked and/or altered in your online account

Let us know how the visit goes.

Best,

[millsley]

Thanks all for the help. 

The engineer came and fixed some external wiring and fiddled with the router. After using the connection for a few days it seems like everything has been resolved.

Ta,

M

[Martin_N]

We're glad to hear this has all been sorted for you millsley.

^Martin