No Ranged Response Received and T3 Time Out

[grayfitz]

Hi all,

We've been experiencing a lot of brief dropout over the last few days on our home network. After a bit of searching I think we need to call an engineer out, but was hoping for an opinion from more knowledge people first! I confirmed through the Virgin Media network service checker (0800 561 0061) that there's no issues in the area.

Downstream bonded channels

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

1	203000000	-1.2	38	256 qam	9
2	211000000	-1.2	38	256 qam	10
3	219000000	-1.2	38	256 qam	11
4	227000000	-1.4	38	256 qam	12
5	235000000	-1.5	38	256 qam	13
6	243000000	-1.5	38	256 qam	14
7	251000000	-1.7	38	256 qam	15
8	259000000	-1.5	38	256 qam	16
9	267000000	-1.5	38	256 qam	17
10	275000000	-1.7	38	256 qam	18
11	283000000	-1.9	38	256 qam	19
12	291000000	-2	38	256 qam	20
13	299000000	-1.7	38	256 qam	21
14	307000000	-1.4	38	256 qam	22
15	315000000	-1	38	256 qam	23
16	323000000	-0.7	38	256 qam	24
17	331000000	-0.7	38	256 qam	25
18	339000000	-0.2	38	256 qam	26
19	347000000	-0.2	38	256 qam	27
20	355000000	0	38	256 qam	28
21	363000000	0	38	256 qam	29
22	371000000	0	38	256 qam	30
23	379000000	0	38	256 qam	31
24	387000000	0.2	38	256 qam	32

Downstream bonded channels

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

1	Locked	38.9	78	0
2	Locked	38.9	39	0
3	Locked	38.6	70	0
4	Locked	38.6	73	0
5	Locked	38.9	77	0
6	Locked	38.9	92	0
7	Locked	38.9	111	0
8	Locked	38.6	101	0
9	Locked	38.9	92	0
10	Locked	38.6	109	0
11	Locked	38.9	156	0
12	Locked	38.9	233	0
13	Locked	38.6	205	0
14	Locked	38.6	123	0
15	Locked	38.9	97	0
16	Locked	38.9	84	0
17	Locked	38.6	85	0
18	Locked	38.6	57	0
19	Locked	38.9	49	0
20	Locked	38.9	70	0
21	Locked	38.9	40	0
22	Locked	38.9	40	0
23	Locked	38.6	34	0
24	Locked	38.9	74	95

[grayfitz]

Upstream bonded channels

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

1	53700625	49	5120	16 qam	2
2	39399991	49	5120	64 qam	4
3	46200029	49	5120	32 qam	3
4	60299551	48.8	5120	32 qam	1

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1	ATDMA	0	0	126	0
2	ATDMA	0	0	0	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0

Network Log

Time Priority Description

24/05/2022 20:22:27	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:18:44	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:12:49	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:11:1	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:10:53	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:10:52	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:10:52	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 20:10:50	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 11:24:24	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/05/2022 00:44:39	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
01/01/1970 00:01:42	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
21/05/2022 16:26:59	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
21/05/2022 05:47:34	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
20/05/2022 02:34:52	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:41:21	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:41:21	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:41:21	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:40:36	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:40:35	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
19/05/2022 20:40:35	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

[newapollo]

The down stream is odd in showing that you have 95 post RS errors on channel 24.  There are usually more pre RS errors than post RS errors.

You seem to have a lot of T3 errors. They mean the hub has not had a response from the CMTS to its upstream ranging requests that keep everything working at the right frequency and power, often due to upstream RF noise 

I suggest that you check all your cabling, especially the white coaxial cable. Ensure it is snug and tight with no kinks, it can often work loose, especially if the other half is hoovering and moves the wires 😉

Loose wiring may also explain why the upstream modulation isn't right. They should all be 64 qam. Upstream bonded channels. Check and tighten the cables and then post your stats again, for one of the morelknowlegable members to check what the problem is and offer assistance. We have some pretty good online guru's on the forum.

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

1	53700625	49	5120	16 qam	2
2	39399991	49	5120	64 qam	4
3	46200029	49	5120	32 qam	3
4	60299551	48.8	5120	32 qam	1

[gnome]

An interesting assessment but I have no idea what it means, due to my lack of understanding.

Is there an easy to understand website that explains what all this stuff means, RS errors, CMTS, etc as I have often wondered what all the Downstream/Upstream figures mean, so that I can understand what is happening at my own router

[newapollo]

Hi @gnome,

You should have a read of the following thread.

community.virginmedia.com/t5/Speed/Hub-status-data-understanding-network-log-messages/