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Monte70car's avatar
Monte70car
Aspirant
Jan 17, 2021

Nighthawk c7800 cable modem

Is it a known issue for a cable modem to go out and come back online within a day or two going out? We have had our nighthawk for a year now no issue until October 2020 when we lost internet for a hol...
plemans's avatar
plemans
Guru - Experienced User
Jan 17, 2021

do you have a screen snip of the cable connections page and the logs? 

those help us more than just telling us what some of the values are. 

 

they don't "change" the power levels. to change them they'd actually have to come out and check lines which is why a call rarely helps the first time. 

  • Monte70car's avatar
    Monte70car
    Aspirant
    Jan 17, 2021
    I do have pictures but they won’t load as the format doesn’t match what’s allowed. And the computer isn’t getting out of the internal network. Plemans the sad part is a tech or so called tech was here. Took his little tool connected to the feed line going up to the modem and saw that the modem was offline and he did a reboot via his cell phone.
    • plemans's avatar
      plemans
      Guru - Experienced User
      Jan 17, 2021

      Not giving you grief but if the modem's offline, he couldn't have remote rebooted/reset it. Since it isn't online. 

       

      If you take a screensnip, it should be in the proper format and you can click on "choose file" to add. 

      • Monte70car's avatar
        Monte70car
        Aspirant
        Jan 17, 2021
        Plemans here is what I am able to grab from modem. I’m not 100% but shouldn’t downstream and upstream kinda match? Also the log is here as well second set of line items. As for screen shoots my iPhone comes up as jpeg.
        Downstream OFDM Channels
        Channel Channel ID Indicator Subcarrier Zero Frequency Active Subcarrier Number Range Total Codewords Uncorrectable Codewords
        1 25 Non-Primary 713600000 Hz 1108 ~ 2987 2431991 0
        2 0 Other 0 Hz 0 ~ 0 0 0
        Upstream OFDMA Channels
        Channel UpstreamIsMuted Ranging Status Subcarrier Zero Frequency Active Subcarrier Number Range Symbols Per Frame Tx Power
        1 Other 0 Hz 0 ~ 0 0 0 dBmV
        2 Other 0 Hz 0 ~ 0 0 0 dBmV
        Current System Time: Sun, Jan 17, 2021 18:07:21







        Time Priority Description
        2021-01-17, 11:03:02 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
        Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:48:36 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:47:28 Critical (3) Resetting the cable modem due to docsDevResetNow
        2021-01-17, 08:46:44 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:42:10 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:41:53 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:41:53 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:41:08 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM-QOS=1.1;CM-VER=3.1;
        2021-01-17, 08:41:07 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:ce:b3:00;CMTS-MAC=00:01:5c:71:72:67;CM

        [remote login] from source fe80::1025:7716:83b:2f5b, Sun, Jan 17, 2021 18:05:39
        [admin login] from source 192.168.0.38, Sun, Jan 17, 2021 18:04:22
        [DHCP IP: (192.168.0.38)] to MAC address e2:ce:43:82:94:b9, Sun, Jan 17, 2021 18:03:47
        [DHCP IP: (192.168.0.3)] to MAC address 00:05:cd:39:fb:e0, Sun, Jan 17, 2021 16:58:06
        [Internet connected] IP address: 73.134.72.134, Sun, Jan 17, 2021 16:49:04
        [Internet disconnected] Sun, Jan 17, 2021 16:48:35
        [Internet disconnected] Sun, Jan 17, 2021 16:48:35
        [DHCP IP: (192.168.0.37)] to MAC address d8:0f:99:5f:f5:81, Sun, Jan 17, 2021 16:37:15
        [DHCP IP: (192.168.0.35)] to MAC address 0a:93:e2:1b:e8:27, Sun, Jan 17, 2021 16:30:25
        [DHCP IP: (192.168.0.34)] to MAC address c8:fd:19:80:ce:95, Sun, Jan 17, 2021 16:06:19
        [DHCP IP: (192.168.0.29)] to MAC address 00:7c:2d:2a:45:9e, Sun, Jan 17, 2021 16:05:04
        [DHCP IP: (192.168.0.23)] to MAC address 98:84:e3:db:15:61, Sun, Jan 17, 2021 16:04:25