Menu
Reply
jgtimperley
  • 108
  • 3
  • 39
Up to speed
933 Views
Message 1 of 11
Flag for a moderator

Upstream noise WA15

Hi all,

I'm mainly posting here for a Virgin rep to confirm my diagnosis (upstream noise) and give me a fault ref, but of course other contributions are welcome. I'm a long-time lurker here, so know of the noise issues that can arise on HFC/DOCSIS networks, especially in the lower upstream frequencies.

First of all, all connections are finger tight, cables unkinked and unmodified since my install back in 2017. Connection has been generally reliable over the last 4.5 years with the odd noise issue that was quickly resolved, up until the last few weeks, where noise issues (mainly affecting upstream frequencies) seem to be intermittent but persistent. Download speeds are as expected (350-380Mbps), upload speeds are slightly lower than expected (28Mbps instead of the usual 36Mbps).

Today's graph (link)

Live graph (link)

Stats from this morning, before I rebooted (as seen on the graph around 10AM):

Upstream bonded channels
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 46200000 40 5120 64 qam 11
2 25800000 40.2 5120 16 qam 14
3 32600000 40 5120 64 qam 13
4 39400000 40 5120 64 qam 12


Upstream bonded channels
Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
1 ATDMA 0 0 1 0
2 ATDMA 0 0 208 0
3 ATDMA 0 0 0 0
4 ATDMA 0 0 1 0


Downstream bonded channels
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 330750000 -0.7 40 256 qam 25
2 266750000 -0.7 38 256 qam 17
3 274750000 -0.9 40 256 qam 18
4 282750000 -0.5 40 256 qam 19
5 290750000 -0.5 40 256 qam 20
6 298750000 -0.4 38 256 qam 21
7 306750000 -0.5 40 256 qam 22
8 314750000 -0.7 40 256 qam 23
9 322750000 -0.5 40 256 qam 24
10 338750000 -0.9 38 256 qam 26
11 346750000 -0.9 40 256 qam 27
12 354750000 -0.7 40 256 qam 28
13 362750000 -0.7 40 256 qam 29
14 370750000 -0.7 40 256 qam 30
15 378750000 -0.7 38 256 qam 31
16 386750000 -0.7 40 256 qam 32
17 394750000 -0.5 40 256 qam 33
18 402750000 -0.5 40 256 qam 34
19 410750000 -0.4 40 256 qam 35
20 418750000 -0.2 40 256 qam 36
21 426750000 0 40 256 qam 37
22 434750000 0 40 256 qam 38
23 442750000 0 40 256 qam 39
24 450750000 0 40 256 qam 40


Downstream bonded channels
Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 Locked 40.3 316 0
2 Locked 38.9 229 0
3 Locked 40.3 279 0
4 Locked 40.3 219 0
5 Locked 40.3 166 0
6 Locked 38.6 209 0
7 Locked 40.3 191 0
8 Locked 40.3 256 0
9 Locked 40.3 262 0
10 Locked 38.9 536 0
11 Locked 40.3 560 0
12 Locked 40.3 826 0
13 Locked 40.3 1521 0
14 Locked 40.3 4045 0
15 Locked 38.9 10209 45
16 Locked 40.3 20918 100
17 Locked 40.3 48325 56
18 Locked 40.3 97198 0
19 Locked 40.9 217220 0
20 Locked 40.3 334935 0
21 Locked 40.3 566757 0
22 Locked 40.3 886000 0
23 Locked 40.3 1305665 0
24 Locked 40.9 2000720 0

Stats after reboot:

Upstream bonded channels
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 46200000 40 5120 32 qam 11
2 25800000 40 5120 16 qam 14
3 32600000 40 5120 32 qam 13
4 39400000 40 5120 32 qam 12


Upstream bonded channels
Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
1 ATDMA 0 0 0 0
2 ATDMA 0 0 88 0
3 ATDMA 0 0 0 0
4 ATDMA 0 0 0 0

Downstream bonded channels
Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 Locked 40.9 6 0
2 Locked 40.3 5 0
3 Locked 40.3 7 0
4 Locked 40.3 7 0
5 Locked 40.3 6 0
6 Locked 38.9 5 0
7 Locked 40.3 6 0
8 Locked 40.3 8 0
9 Locked 38.9 6 0
10 Locked 38.9 9 0
11 Locked 40.3 4 0
12 Locked 40.3 12 0
13 Locked 40.3 9 0
14 Locked 40.3 5 0
15 Locked 38.9 10 0
16 Locked 40.9 24 0
17 Locked 40.3 8 0
18 Locked 40.3 6 0
19 Locked 40.3 9 0
20 Locked 40.3 9 0
21 Locked 40.3 7 0
22 Locked 40.3 13 0
23 Locked 40.3 8 0
24 Locked 40.3 0 0

0 Kudos
Reply
jgtimperley
  • 108
  • 3
  • 39
Up to speed
932 Views
Message 2 of 11
Flag for a moderator

Re: Upstream noise WA15

Network Log:

Time Priority Description
30/08/2021 15:22:2 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
28/08/2021 16:59:6 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
28/08/2021 16:50:34 notice DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt062-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
28/08/2021 16:50:34 Error DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
26/08/2021 10:51:34 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
25/08/2021 10:41:55 notice DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt062-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
25/08/2021 10:41:55 Error DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:33:7 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:33:7 critical Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:29:8 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:29:8 critical Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:27:48 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:27:48 critical Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:26:48 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:26:48 critical Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:22:28 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:22:28 critical Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2021 20:19:29 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

0 Kudos
Reply
jgtimperley
  • 108
  • 3
  • 39
Up to speed
921 Views
Message 3 of 11
Flag for a moderator

Re: Upstream noise WA15

Also, status line (0800 561 0061) identifies a fault, and offers to text me a link, which then shows no fault!

Hub 3 is currently in modem mode, happy to switch to router mode for testing if needed.

Internet usability, including Sipgate VoIP is suprisingly fine. Two of us working from home tomorrow could be exciting, we have the mobile hotspots ready for action, although the loss does seem to be low enough for UDP to deal with it for the time being.

0 Kudos
Reply
Paulina_Z
  • 3.58K
  • 126
  • 260
Forum Team
Forum Team
804 Views
Message 4 of 11
Flag for a moderator
Helpful Answer

Re: Upstream noise WA15

Hi @jgtimperley,

 

Welcome back to our Community Forums! Thank you for your post, and I'm sorry to hear that you're experiencing some issues with your upstream noise and connection!

 

I can understand that this can be very frustrating. That is very strange that the text you receive does not state an area fault!

 

After looking into your account, I can confirm, that there is a live SNR (Signal to Noise Ratio) outage in your area. The fault reference number is F009244088, and the area issue has a listed estimated fix date and time for 06/09/21 at 11am.

 

Apologies that you're impacted by this issue. I have raised a Work Order on our system, so we're aware that you're experiencing this issue.

 

Please keep in touch and let us know if you're still experiencing issues after the outage has been resolved, so we can help further if needed.

 

Thank you! 🙂

Paulina_Z
Forum Team



New around here? To find out more about the Community check out our Getting Started guide


jgtimperley
  • 108
  • 3
  • 39
Up to speed
795 Views
Message 5 of 11
Flag for a moderator

Re: Upstream noise WA15


@Paulina_Z wrote:

After looking into your account, I can confirm, that there is a live SNR (Signal to Noise Ratio) outage in your area. The fault reference number is F009244088, and the area issue has a listed estimated fix date and time for 06/09/21 at 11am.

Apologies that you're impacted by this issue. I have raised a Work Order on our system, so we're aware that you're experiencing this issue.


Thank you Paulina_Z, that's very helpful and exactly the confirmation I was looking for. We're away for two weeks after the weekend, so I'll check when I get back and report back here.

In terms of working from home, it's been fairly disruptive. Teams calls work surprisingly well, but with a noticable delay/loss of quality. SSH sessions in particular are frustrating, and are a large part of my job. The upload speed is  down to around 7Mb during the day, which is considerably lower than the 35Mb we usually get.

Today's BQM graph for future reference.

Cheers,

Jon

0 Kudos
Reply
jgtimperley
  • 108
  • 3
  • 39
Up to speed
794 Views
Message 6 of 11
Flag for a moderator

Re: Upstream noise WA15

By the way, has anyone ever seen this many T3 timeouts in ~60 hours?:

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1ATDMA0000
2ATDMA003320
3ATDMA0000
4ATDMA0020
0 Kudos
Reply
Tom_F
  • 4.22K
  • 250
  • 537
Forum Team (Retired)
Forum Team (Retired)
717 Views
Message 7 of 11
Flag for a moderator

Re: Upstream noise WA15

Apologies jgtimperley, we understand these things are never ideal. Rest assured the relevant teams will be working hard to ensure things are back to normal asap - as things stand the estimated fix-time has not changed it's still on track to be fixed by Monday.

 

Tom 

0 Kudos
Reply
jgtimperley
  • 108
  • 3
  • 39
Up to speed
438 Views
Message 8 of 11
Flag for a moderator

Re: Upstream noise WA15

No response needed from VM here, just logged into my account for the first time in a while and noticed I didn't update. Hate to leave things unresolved, especially for future visitors to this forum.

Shortly after we got back from the 2 weeks away in Sept (seems like decades ago now!), I ordered a PlusNet backup line (~30Mb due to long-line to FTTC cab). It's cheap enough considering two of us work from home and rely so much on the internet these days for VoIP and TV/Sonos etc. That being said, we have only had to use it maybe once, as the VM line has been rock solid ever since this noise issue was resolved.

The final resolution seems to have been VM turning off the hugely problematic 25.8Mhz channel (and possibly also addressing some noise that was occasionally bleeding into the other US channels).

Speed and stability now back to the normal, which I'm fortunate to say is good for me/my location. Fingers crossed they don't need to turn 25.8 back on again - I understand this was due to increased upload demand due to home-working. I work in this industry, so fully understand and appreciate the challenges that running an access network presents, and all the hard work that VM put into this (even if it is frustrating at times!).

0 Kudos
Reply
Anonymous
Not applicable
430 Views
Message 9 of 11
Flag for a moderator

Re: Upstream noise WA15

The 25.8 channel is VM's standard channel plan.

If there's enough noise for too long channels can drop offline.

I guess they aren't able to isolate the source of the noise. Blocks of flats are often a culprit. 

jgtimperley
  • 108
  • 3
  • 39
Up to speed
421 Views
Message 10 of 11
Flag for a moderator

Re: Upstream noise WA15

Interesting. I was under the impression that areas could have non-standard channel-plans, to cater for situations like this. Is that not the case? I've not locked onto 25.8 since the issue was fixed, and have rebooted a few times.

Not many blocks of flats around here, and definitely not large ones. I have a reasonable idea of the area the segments cover (the optical node is at the top of my street, and there are a few others relatively close by).
0 Kudos
Reply