Forum Discussion

lriley06's avatar
lriley06
On our wavelength
2 months ago

Packet loss, internet dropping out and thousands of post-RS errors per day

Hiya,

I was hoping someone on here could help with this! I'm having realtively frequent issues with my Hub 3 in modem mode - I keep seeing high packet loss or the internet drops out all together for a few seconds from time to time. I have done the oft-quoted steps of "turn off for 5 minutes, check coax connections are all tight and no visible faults in cables, verify post RS error counters have all reset to 0", and I'm still getting issues.

I performed all of those steps last night, and at 16:25 today, I now have thousands of post RS errors on some of the downstream channels. (I will attach info below). I'm not really sure what the issue is though, as I'm pretty sure the power levels and SNRs all look okay?

I haven't had any noticable issues today (although there was apparently a T3 timeout last night!) so there doesn't seem to be anything unusual in the network logs, although you can see messages from some kind of issue a few days ago. Also, the post RS errors have still been creeping up as usual. In fact, before I restarted the Hub 3 last night there were so many post RS errrors that some kind of integer overflow "wraparound" bug seemed to have occured as I was seeing negative Post RS error counts on some channels!

Downstream bonded channels

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

1330750000-1.438256 qam25
2138750000-0.736256 qam1
3146750000-136256 qam2
4154750000-1.237256 qam3
5162750000-1.237256 qam4
6170750000-1.237256 qam5
7178750000-137256 qam6
8186750000-1.237256 qam7
9194750000-1.437256 qam8
10202750000-1.737256 qam9
11210750000-1.937256 qam10
12218750000-238256 qam11
13226750000-2.237256 qam12
14234750000-2.537256 qam13
15306750000-1.938256 qam22
16314750000-1.738256 qam23
17322750000-1.738256 qam24
18338750000-137256 qam26
19346750000-0.938256 qam27
20354750000-0.738256 qam28
21362750000-138256 qam29
22370750000-1.238256 qam30
23378750000-1.938256 qam31
24386750000-2.538256 qam32



Downstream bonded channels

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

1Locked38.920590
2Locked36.64784473978
3Locked36.63577312030
4Locked37.6238340893
5Locked37.3169213407
6Locked37.6128992169
7Locked37.38902261
8Locked37.36109023
9Locked37.9379018
10Locked37.6311180
11Locked37.6236850
12Locked38.6154050
13Locked37.6154470
14Locked37.6161340
15Locked38.638450
16Locked38.629290
17Locked38.622460
18Locked37.623890
19Locked38.616540
20Locked38.612160
21Locked38.69650
22Locked38.67800
23Locked38.67730
24Locked38.9509

0

 

Upstream bonded channels

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

14960001743512064 qam1
22359998843512064 qam5
33009999841.5512064 qam4
43659999641.5512064 qam3
54310000743512064 qam2



Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1ATDMA0000
2ATDMA0000
3ATDMA0000
4ATDMA0000
5ATDMA0010

 

  • Client62's avatar
    Client62
    Alessandro Volta
    2 months ago

    I've occasional seen similar bursts of Post-RS Errors on our Hub,
    it usually occurs when an engineer is connecting a new customer or doing maintenance.

    The signal levels look fine, are the Post-RS error counts still rapidly rising ?
    If the Post-RS errors are now almost static, the local noise fault may be fixed.

  • Beth_G's avatar
    Beth_G
    Forum Team
    2 months ago

    Hi Iriley06

    Thanks for your post. I'm sorry to hear you've been experiencing some packet loss and connection drops recently.

    As Cleint62 has also commented, your signal levels are fine and no issues from our side from what I can see.

    Are you only experiencing these issues in modem mode? 

    If there's been no improvement and you need some help, please pop into router mode for us and let us know when you've done so. We'll then be able to run further diagnostic tests for you.😊

  • lriley06's avatar
    lriley06
    On our wavelength
    2 months ago

    The connection appears to be quite stable now, although I'm still sometimes getting down to 30mbps fairly frequently rather than the usual ~270mbps (yes I tested this when no other devices on my network were using the connection!). The errors are still regularly increasing so I doubt this is down to a maintenance incident. Here are the status pages now (haven't rebooted since the last time I posted them):

    Downstream bonded channels

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

    1330750000-1.238256 qam25
    2138750000-0.536256 qam1
    3146750000-0.737256 qam2
    4154750000-137256 qam3
    5162750000-137256 qam4
    6170750000-0.937256 qam5
    7178750000-0.937256 qam6
    8186750000-137256 qam7
    9194750000-1.238256 qam8
    10202750000-1.437256 qam9
    11210750000-1.537256 qam10
    12218750000-1.738256 qam11
    13226750000-237256 qam12
    14234750000-2.237256 qam13
    15306750000-1.538256 qam22
    16314750000-1.538256 qam23
    17322750000-1.538256 qam24
    18338750000-0.938256 qam26
    19346750000-0.738256 qam27
    20354750000-0.538256 qam28
    21362750000-0.738256 qam29
    22370750000-138256 qam30
    23378750000-1.538256 qam31
    24386750000-2.438256 qam32



    Downstream bonded channels

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

    1Locked38.6339801
    2Locked36.3671945871356
    3Locked37.3503027137663
    4Locked37.3339487516046
    5Locked37.624218397497
    6Locked37.318475143706
    7Locked37.612946741534
    8Locked37.3890789559
    9Locked38.6564685198
    10Locked37.6454623105
    11Locked37.634992136
    12Locked38.62277949
    13Locked37.622848511
    14Locked37.624112040
    15Locked38.6607747
    16Locked38.6465459
    17Locked38.9359505
    18Locked38.6362043
    19Locked38.9262271
    20Locked38.9193860
    21Locked38.6159340
    22Locked38.6131471
    23Locked38.6124310
    24Locked38.68394

    0

     

    Upstream bonded channels

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

    14960001743512064 qam1
    22360000043512064 qam5
    33010000041.5512064 qam4
    43660000041.5512064 qam3
    54310000043512064 qam2



    Upstream bonded channels

    Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

    1ATDMA0000
    2ATDMA0010
    3ATDMA0000
    4ATDMA0040
    5ATDMA0030
  • lriley06's avatar
    lriley06
    On our wavelength
    2 months ago

    And the logs:

    Network Log

    Time Priority Description

    13/12/2024 11:13:6criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    11/12/2024 23:40:55noticeDHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt060-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    11/12/2024 23:40:55ErrorDHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    10/12/2024 21:28:0criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    08/12/2024 11:40:55noticeDHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt060-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    08/12/2024 11:40:55ErrorDHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    07/12/2024 21:31:32criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    06/12/2024 18:29:29noticeLAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    06/12/2024 12:51:19criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    05/12/2024 16:00:21noticeLAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    05/12/2024 03:12:12criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    05/12/2024 00:48:1noticeLAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    04/12/2024 23:40:54noticeDHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt060-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    04/12/2024 23:40:54ErrorDHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    04/12/2024 21:21:9noticeLAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    04/12/2024 04:48:28Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    03/12/2024 19:37:26criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    03/12/2024 13:37:59noticeLAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    02/12/2024 18:42:9criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
    02/12/2024 01:57:25Warning!RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
  • lriley06's avatar
    lriley06
    On our wavelength
    2 months ago

    @Beth_G I would prefer not to put my Hub 3 into modem mode if possible? I'd quite like to avoid disrupting my internet connection as much as possible! I am happy to run any tests that you would like and consider myself reasonbly experienced with networking from my job 🙂

    • Steven_L's avatar
      Steven_L
      Forum Team
      2 months ago

      Thanks for coming back to us lriley06. I would be happy to take a further look into this for you but first I would need to confirm a few details via private message, please look out for my message and we can get started.
      Kind Regards,
      Steven_L