Our modem is a NETGEAR CM500 and in the morning when I woke up, the internet wasn't working. I looked at the modem and the downstream light was blinking green with the other lights solid green besides the Ethernet light which always blinks quick. I have tried resetting it, using a different coax cable, and rebooting it several of times. When I called Spectrum, they said it came through fine on their end. I later found a site NETGEAR provides which shows the logs and the status shows normal on there. This is what the website shows under the Startup Procedure:
Procedure | Status | Comment |
Acquire Downstream Channel | 627000000 Hz | Locked |
Connectivity State | OK | Operational |
Boot State | OK | Operational |
Security | Enabled | BPI+ |
IP Provisioning Mode | IPv6 Only | ipv6Only(1) |
This is what it shows under the "Downstream Bonded Channels (partial service)":
Channel | Lock Status | Modulation | Channel ID | Frequency | Power | SNR | Correctables | Uncorrectables |
1 | Locked | QAM256 | 1 | 627000000 Hz | 3 dBmV | 40 dB | 0 | 0 |
2 | Locked | QAM256 | 4 | 645000000 Hz | 3.6 dBmV | 39.9 dB | 9 | 0 |
3 | Not Locked | Unknown | 5 | 651000000 Hz | 0.0 dBmV | 0.0 dB | 0 | 0 |
4 | Locked | QAM256 | 6 | 657000000 Hz | 3.7 dBmV | 40 dB | 3 | 0 |
5 | Locked | QAM256 | 7 | 663000000 Hz | 4.6 dBmV | 40.2 dB | 2 | 0 |
6 | Locked | QAM256 | 8 | 669000000 Hz | 4.2 dBmV | 40.1 dB | 3 | 0 |
7 | Locked | QAM256 | 9 | 675000000 Hz | 1.7 dBmV | 39.3 dB | 5 | 0 |
8 | Locked | QAM256 | 10 | 681000000 Hz | 2.8 dBmV | 39.7 dB | 3 | 0 |
9 | Locked | QAM256 | 12 | 693000000 Hz | 3.3 dBmV | 39.9 dB | 1 | 0 |
10 | Locked | QAM256 | 13 | 699000000 Hz | 2.4 dBmV | 39.7 dB | 3 | 0 |
11 | Locked | QAM256 | 14 | 705000000 Hz | 1.9 dBmV | 39.6 dB | 0 | 0 |
12 | Locked | QAM256 | 15 | 711000000 Hz | 3.9 dBmV | 39.9 dB | 0 | 0 |
13 | Locked | QAM256 | 16 | 717000000 Hz | 3.1 dBmV | 39.8 dB | 2 | 0 |
14 | Locked | QAM256 | 18 | 729000000 Hz | 2.5 dBmV | 39.8 dB | 0 | 0 |
15 | Locked | QAM256 | 20 | 741000000 Hz | 2.6 dBmV | 39.6 dB | 2 | 0 |
16 | Locked | QAM256 | 23 | 759000000 Hz | 4.3 dBmV | 40 dB | 1 | 0 |
I dont know if the 3rd channel not being locked is a bad thing. Here is what is under the Upstream Bonded Channels:
Channel | Lock Status | US Channel Type | Channel ID | Symbol Rate | Frequency | Power |
1 | Locked | ATDMA | 82 | 5120 Ksym/sec | 24200000 Hz | 36.5 dBmV |
2 | Locked | TDMA | 81 | 2560 Ksym/sec | 19400000 Hz | 36.5 dBmV |
3 | Locked | ATDMA | 83 | 5120 Ksym/sec | 30600000 Hz | 35.5 dBmV |
4 | Locked | ATDMA | 84 | 5120 Ksym/sec | 37000000 Hz | 38.3 dBmV |
Here is the Event Logs:
Time | Priority | Description |
1970-1-1, 00:00:20 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:36 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:36 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:47 | Critical (3) | DHCP FAILED - Discover sent, no offer received;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:01:5c:8b:50:68;CM-QOS=1.0;CM-VER=3.0; |
2018-6-8, 00:05:15 | Critical (3) | No Ranging Response received - T3 time-out;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:01:5c:8b:50:68;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:21 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:20 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:21 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
1970-1-1, 00:00:28 | Notice (6) | Overriding MDD IP initialization parameters; IP provisioning mode = IPv6 |
2018-6-7, 20:11:03 | Error (4) | Missing BP Configuration Setting TLV Type: 17.8;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:01:5c:8b:50:68;CM-QOS=1.1;CM-VER=3.0; |
2018-6-7, 20:11:03 | Error (4) | Missing BP Configuration Setting TLV Type: 17.9;CM-MAC=2c:30:33:17:53:60;CMTS-MAC=00:01:5c:8b:50:68;CM-QOS=1.1;CM-VER=3.0; |
When I researched this up, it said that it might lie in the coax cable from outside, but I looked out there and everything looked fine from the grounding block. Is there anything you could get from this that explains why the downstream light is blinking and the internet is down?
@rinehartpa wrote:Our modem is a NETGEAR CM500 and in the morning when I woke up, the internet wasn't working. I looked at the modem and the downstream light was blinking green with the other lights solid green besides the Ethernet light which always blinks quick. I have tried resetting it, using a different coax cable, and rebooting it several of times. When I called Spectrum, they said it came through fine on their end. I later found a site NETGEAR provides which shows the logs and the status shows normal on there. This is what the website shows under the Startup Procedure:
Procedure Status Comment Acquire Downstream Channel 627000000 Hz Locked Connectivity State OK Operational Boot State OK Operational Security Enabled BPI+ IP Provisioning Mode IPv6 Only ipv6Only(1) This is what it shows under the "Downstream Bonded Channels (partial service)":
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 1 627000000 Hz 3 dBmV 40 dB 0 0 2 Locked QAM256 4 645000000 Hz 3.6 dBmV 39.9 dB 9 0 3 Not Locked Unknown 5 651000000 Hz 0.0 dBmV 0.0 dB 0 0 4 Locked QAM256 6 657000000 Hz 3.7 dBmV 40 dB 3 0 5 Locked QAM256 7 663000000 Hz 4.6 dBmV 40.2 dB 2 0 6 Locked QAM256 8 669000000 Hz 4.2 dBmV 40.1 dB 3 0 7 Locked QAM256 9 675000000 Hz 1.7 dBmV 39.3 dB 5 0 8 Locked QAM256 10 681000000 Hz 2.8 dBmV 39.7 dB 3 0 9 Locked QAM256 12 693000000 Hz 3.3 dBmV 39.9 dB 1 0 10 Locked QAM256 13 699000000 Hz 2.4 dBmV 39.7 dB 3 0 11 Locked QAM256 14 705000000 Hz 1.9 dBmV 39.6 dB 0 0 12 Locked QAM256 15 711000000 Hz 3.9 dBmV 39.9 dB 0 0 13 Locked QAM256 16 717000000 Hz 3.1 dBmV 39.8 dB 2 0 14 Locked QAM256 18 729000000 Hz 2.5 dBmV 39.8 dB 0 0 15 Locked QAM256 20 741000000 Hz 2.6 dBmV 39.6 dB 2 0 16 Locked QAM256 23 759000000 Hz 4.3 dBmV 40 dB 1 0 I dont know if the 3rd channel not being locked is a bad thing. Here is what is under the Upstream Bonded Channels:
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 82 5120 Ksym/sec 24200000 Hz 36.5 dBmV 2 Locked TDMA 81 2560 Ksym/sec 19400000 Hz 36.5 dBmV 3 Locked ATDMA 83 5120 Ksym/sec 30600000 Hz 35.5 dBmV 4 Locked ATDMA 84 5120 Ksym/sec 37000000 Hz 38.3 dBmV When I researched this up, it said that it might lie in the coax cable from outside, but I looked out there and everything looked fine from the grounding block. Is there anything you could get from this that explains why the downstream light is blinking and the internet is down?
Not too difficult - your modem cannot receive the encrypted digital signal that it expects to find on DS3 (651 MHz). Since the modem can't 'hear' the information supposedly being sent out on channel DS3, it can't assemble complete data packets addressed to your computer.
If you try to call this in to Spectrum's normal "Tier 1" tech resource, they won't know what you are talking about. You need to have a tech come out and view those modem signal level reports. Print out a copy before you unplug power or do a factory reset on the modem - those are Tech Support's two favorite ways to "fix your connection" that also erase the data log in your modem.
The fault is most likely on Spectrum's side at the cable-to-fiber interface out along ther trunk route. It will probably be one bad card in the shelf of eight, or a bad fiber in the bundle from the node.
If you kept the manual for your modem, page 6 of the Netgear CM500 User Guide says:
Table 1. LED descriptions
LED
Description
Power
• Green. Power is supplied to the cable modem.
• Off. No power is supplied to the cable modem.
• Red. The cable modem is too warm and might overheat. For more information about this condition, see Use LEDs to Troubleshoot on page 24.
Downstream
• Solid amber. One downstream channel is locked.
• Blinking amber. The cable modem is scanning for a downstream channel.
• Solid green. More than one downstream channel is locked.
• Off. No downstream channel is locked.
Upstream
• Solid amber. One upstream channel is locked.
• Blinking amber. The cable modem is scanning for an upstream channel.
• Solid green. More than one upstream channel is locked.
• Off. No upstream channel is locked.
Internet
• Solid green. The cable modem is online.
• Blinking green. The cable modem is synchronizing with the cable Internet provider’s cable modem termination system (CMTS).
• Off. The cable modem is offline.
Ethernet
• Green. A powered-on device is connected to the Ethernet port at 1000 Mbps.
• Amber. A powered-on device is connected to the Ethernet port at 10/100 Mbps.
• Blinking green or amber. The Ethernet port is processing traffic.
• Off. No device is connected to the Ethernet port.
@rinehartpa Are you still experiencing issues?
If the issue was resolved did you have to perform any steps? Had you spoken with support?
We would like to have some more detail about how things are going now.
Regards,
Julia R.
Spectrum-Social Media Customer Care
Lead Moderator-Community Forums
So later after this post when I went to plug the modem directly into the computer with an ethernet connection, it was able to load some pages at first very slowly and then a minute later it was able to load pages fine.
When the technican came I was not there, but they said they reset the router and it was working again, to where I am right now. The wifi is working again, but the DS light is still flashing on it. Since I was not there, I was not able to describe to the technician that it was something going on from outside to modem because of the DS light blinking. To karlbeckman, it is flashing green, not amber, and that was not in the manual. I still do not believe the problem has been fixed fully, it was just patched for now.