C7800

Have the ISP check the signal and line quality UP to the modem. 
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 

Please edit out any MAC and WAN IP address information before posting in public forums. 

Thank you, 

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ThrowAwayName4 wrote:

Hi Everyone,
 I bought the C7800 to use at my house with Comcast being my ISP. When I hook it up I get the 'Firmware is being updated' message (I have V3.01.40) Nothing happens after that. I've been on the phone with Customer Support for both Netgear and Comcast. Netgear just provided the usual 'Factory Reboot' suggestion after spending about 2 hours on the phone with them (It did not work for me). I've probably spent about 6 hours on the phone with Comcast so far troubeshooting. I have a phone call again with them Wednesday but here is where we left off before calling it a night. I'll keep this updated so others can perhaps learn from this. This is far from an isolated incident and seems to have started 9 months ago. This also happened with a second C7800 I bought thinking perhaps the first one was broken.

1. We were able to get a connection that was really slow for downloading (2 mbps) but decent for upload (30 mpbs)
2. The firmware stayed the same.
3. Here are the logs I was able to see.

admin login] from source 192.168.0.2, Tue, Jul 07, 2020 01:56:13
[Time synchronized with NTP server] Tue, Jul 07, 2020 01:52:09
[Internet connected] IP address: 76.100.225.0, Thu, Jan 01, 1970 00:04:36
[admin login] from source 192.168.0.2, Thu, Jan 01, 1970 00:01:54
[admin login] from source 192.168.0.2, Thu, Jan 01, 1970 00:01:53
[DHCP IP: (192.168.0.3)] to MAC address 9c:b6:d0:67:4c:57, Thu, Jan 01, 1970 00:00:59
[DHCP IP: (192.168.0.2)] to MAC address 30:9c:23:13:af:7b, Thu, Jan 01, 1970 00:00:24
[Initialized, firmware version: V3.01.40] Thu, Jan 01, 1970 00:00:06

Second log

2020-07-06, 20:54:22 Critical (3) No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
2020-07-06, 20:54:22 Error (4) SW upgrade Failed after download - SW File corruption
2020-07-06, 20:51:42 Critical (3) No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
2020-07-06, 20:51:35 Notice (6) SW Download INIT - Via Config file d11_m_c7800_gigabit_c01.cm
2020-07-06, 20:51:32 Critical (3) No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
2020-07-06, 20:51:17 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;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=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:01:5c:6e:18:60;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=bc:a5:11:8c:13:c4;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Warning (5) Lost MDD Timeout;CM-MAC=bc:a5:11:8c:13:c4;CMTS-MAC=00:00:00:00:00:00;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=bc:a5:11:8c:13:c4;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

 

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