Menu
Reply
HarryBaker
  • 19
  • 0
  • 0
Tuning in
290 Views
Message 1 of 11
Flag for a moderator

High Packet Loss, should I contact VM?

I'm having a lot of high latency and packet drops this morning and a BQM shows that it there as well indicating it's not an internal issue.

 

I've run a test online and it is indicating there are no faults and everything is good. All the equipment in the house has been restarted so there's still clearly an issue somewhere.

Is it worth me contacting VM? Does the graph above prove a line issue?

0 Kudos
Reply
MikeRobbo
  • 15.27K
  • 1.17K
  • 1.94K
Alessandro Volta
286 Views
Message 2 of 11
Flag for a moderator
Helpful Answer

Re: High Packet Loss, should I contact VM?

Please post a 'Live Link' to your BQM on here straight away.

Instructions for posting BQM Live Link

Under your BQM graph are two links in red.

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 in the ‘text to display’ box write My BQM then click OK - you can post the link straight away.


*********************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************
BT Smart Hub 2 with 70Mbs Download,18Mbs Upload, 9.17ms Latency & 0.35ms Jitter.
MikeRobbo
  • 15.27K
  • 1.17K
  • 1.94K
Alessandro Volta
284 Views
Message 3 of 11
Flag for a moderator

Re: High Packet Loss, should I contact VM?

Can you please

Type 192.168.0.1 (192.168.100.1 in Modem mode) into your browser URL bar and press enter. 

Hub 2 & 3 When the page appears DO NOT LOG IN but click ‘Check Router Status’.

Hub 4 When the page appears LOG IN then Advanced Settings > Tools > Network Status.

Please do not use screen shots.

Copy and paste the contents of the Downstream, Upstream, Configuration and Network Log tabs onto here, if you get a yellow / straw box warning click the Post button again.

Use one post for each tab if you wish.

A Guru will be along soon to decipher the info.


*********************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************
BT Smart Hub 2 with 70Mbs Download,18Mbs Upload, 9.17ms Latency & 0.35ms Jitter.
Andruser
  • 5.55K
  • 974
  • 2.29K
Very Insightful Person
Very Insightful Person
282 Views
Message 4 of 11
Flag for a moderator
Helpful Answer

Re: High Packet Loss, should I contact VM?

Yes, contact VM.  The BQM doesn't show persistent packet loss, there's a little bit between 12pm and 2pm, but the red, blue and high yellow spikes suggests a noise or power problem that's interrupting the connection, and that should be resolvable.  Often that's a simple upstream noise or power issue, but there are other possible causes.  You could post the hub's status data here and we could take a look, but any firm conclusions need to be made by VM, and probably resolved by a field technician, so perhaps worth trying the phone.  

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

HarryBaker
  • 19
  • 0
  • 0
Tuning in
262 Views
Message 5 of 11
Flag for a moderator

Re: High Packet Loss, should I contact VM?

Thanks people. Touch wood it seems to have settled down now. I'm working this morning and was making it impossible but has been fine since this post.

 

For reference the live link is here https://www.thinkbroadband.com/broadband/monitoring/quality/share/690052666b1ca5df591395692afd17c923... 

I'll see how it goes and if spikes again check the router status page.

Just out of interest, is there a VM doc anywhere that explains the metrics on the Router Status and what is what? 

0 Kudos
Reply
tehwolf
  • 1.66K
  • 272
  • 408
Superfast
256 Views
Message 6 of 11
Flag for a moderator

Re: High Packet Loss, should I contact VM?


@HarryBaker wrote

Just out of interest, is there a VM doc anywhere that explains the metrics on the Router Status and what is what? 


Not that I am aware of but there is this, written by a community member, that has a lot of info in it...

0 Kudos
Reply
Andruser
  • 5.55K
  • 974
  • 2.29K
Very Insightful Person
Very Insightful Person
245 Views
Message 7 of 11
Flag for a moderator
Helpful Answer

Re: High Packet Loss, should I contact VM?

Sephiroth's primer is a superb resource, but it is a little difficult to pull out values that might indicate a problem for the hub.  The nature of DOCSIS is 5% science, 85% magic, 10% luck, so there's quite a tolerance built in, and usually to confirm a problem you'd want to have evidence of a customer problems (poor or erratic speed, disconnections, latency), and then something in the hub's status that's not right.  You can have values outside of those I suggest below, yet no connection issues whatsoever, because of the levels of tolerance and redundancy that DOCSIS allows.

The numbers I apply, that are not official but have had some limited steering from VM staff, are:

Downstream

Power levels should be above -5 dBmV and below +10 dBmV

Range of power values shouldn't exceed 5 dBmV

Signal to Noise ratio should not be less than 35 dB on any channel

Post-RS error levels should not be increasing across time on any channel.  The odd few may not be an issue, but these are uncorrectable errors and indicate a problem.  The pre-RS error counts are usually not a problem in themselves, although they can be a precursor to other issues.

On a Hub 4 there will be a downstream DOCSIS 3.1 channel as well.  Normally this operates at 4096 QAM, but can go as low as 1024 QAM and (in theory) still be fine.  Power levels should be as above, SNR probably needs to be at least 37 dBmV.

Upstream

Should be four upstream channels

All power levels should be above 35 dBmV, but below 50 dBmV

All 4 channels should be operating at 64 QAM

Timeout errors should not be more than one or two across all channels.

 

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

HarryBaker
  • 19
  • 0
  • 0
Tuning in
228 Views
Message 8 of 11
Flag for a moderator

Re: High Packet Loss, should I contact VM?

Ok so it's gone again so here's the results of the router status:
I can see some of the downstream is -2.7 and -3.2, not sure if that indicates an issue based on @andruser's post?

Downstream bonded channels

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

11387500000.536256 qam1
21467500000.936256 qam2
31547500000.536256 qam3
41627500000.436256 qam4
51707500000.537256 qam5
6178750000036256 qam6
7186750000037256 qam7
8194750000-0.237256 qam8
9202750000-0.537256 qam9
10210750000-137256 qam10
11218750000-137256 qam11
12226750000-237256 qam12
13234750000-237256 qam13
14242750000-2.737256 qam14
15250750000-3.237256 qam15
16258750000-1.437256 qam16
17266750000-1.237256 qam17
18274750000-0.538256 qam18
19282750000-0.437256 qam19
20290750000-0.437256 qam20
21298750000037256 qam21
22306750000-0.238256 qam22
233147500000.538256 qam23
24322750000038256 qam24

 

Upstream bonded channels

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

12579990844512064 qam4
24620000045.3512064 qam1
33940000044.8512064 qam2
43260000044.3512064 qam3



Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1ATDMA0010
2ATDMA0000
3ATDMA0000
4ATDMA0000

 

General Configuration

Network access
Allowed
Maximum Number of CPEs
1
Baseline Privacy
Enabled
DOCSIS Mode
Docsis30
Config file
cmreg-vmdg505-bbt060-b.cm



Primary Downstream Service Flow

SFID47370
Max Traffic Rate230000061
Max Traffic Burst42600
Min Traffic Rate0



Primary Upstream Service Flow

SFID47369
Max Traffic Rate22000061
Max Traffic Burst42600
Min Traffic Rate0
Max Concatenated Burst42600
Scheduling TypeBestEffort

 

Network LogTime Priority Description
16/01/2021 10:49:23criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
16/01/2021 10:32:10criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
16/01/2021 07:56:7criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
16/01/2021 07:50:27criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
16/01/2021 03:19:18criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
15/01/2021 13:13:56criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
15/01/2021 13:11:51Warning!Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:51:4criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:51:2criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:51:1criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:49:37Warning!Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:49:33criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:49:33Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/01/2021 20:49:33criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
01/01/1970 00:01:47criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/01/2021 02:17:11noticeSW download Successful - Via NMS
13/01/2021 02:15:47noticeSW Download INIT - Via NMS
12/01/2021 17:50:8criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/01/2021 14:42:52ErrorDHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/01/2021 11:26:28Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;



Downstream bonded channels

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

1Locked36.314011001089887
2Locked36.6169786520977
3Locked36.68619
4Locked36.611478
5Locked37.38508
6Locked36.6131712
7Locked37.310038
8Locked37.310937
9Locked37.69928
10Locked37.311808
11Locked37.311726
12Locked37.69794
13Locked37.625425
14Locked37.65852
15Locked37.35451
16Locked37.34190
17Locked37.63060
18Locked38.62700
19Locked37.62120
20Locked37.61720
21Locked37.61360
22Locked38.61140
23Locked38.61020
24Locked38.6960

 

 
0 Kudos
Reply
Andruser
  • 5.55K
  • 974
  • 2.29K
Very Insightful Person
Very Insightful Person
204 Views
Message 9 of 11
Flag for a moderator
Helpful Answer

Re: High Packet Loss, should I contact VM?

The downstream power is within the -5 to +10 range, that's OK, the range of power levels is 4.1 dBmV that's a little high, but should be acceptable, but the uncorrected (post-RS) error counts on channels 1 and 2 is far too high, and the network log shows the hub is repeatedly losing synchronisation and dropping channels, which would cause slow speeds and disconnects.

I'll flag this for the forum staff to advise.  Could be an area noise problem, could be unique to your line.  If it's your line they can arrange a technician without having to gamble on the phone response.

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks

HarryBaker
  • 19
  • 0
  • 0
Tuning in
145 Views
Message 10 of 11
Flag for a moderator

Re: High Packet Loss, should I contact VM?

Much appreciated, bad again today and struggling to work so hopefully the forum staff have the answer 🙂

0 Kudos
Reply