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Re: Cm600 connection issues xfinity
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I spoke to support desk for xfinity and they said my line is clean and shows a healthy signal. They suggested I try manufacture support and here I am.
Any help would be appreciated.
Thanks
Checking on the cm600 logs I noticed that I only have 1 Upstream bonded channel locked, but should have more.
1 Locked ATDMA 3 5120 Ksym/sec 22800000 Hz 57.0 dBmV
Here's the event log
Time Priority Description
2024-12-11, 12:49:18 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:48:29 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:48:23 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:47:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:47:31 Critical (3) No UCDs Received - Timeout;;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:47:11 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:46:26 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:46:22 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:49 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:27 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:23 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:22 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:11 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:10 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:07 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:45:00 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:44:57 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:44:04 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:43:17 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:43:13 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:42:22 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:41:31 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:41:24 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:40:41 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:39:50 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:38:13 Critical (3) No UCDs Received - Timeout;;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:37:56 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:37:51 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:37:43 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:37:31 Critical (3) REG RSP not received;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:36:05 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:36:00 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:35:13 Critical (3) No UCDs Received - Timeout;;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:34:56 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:34:51 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:34:03 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.0;CM-VER=3.0;
2024-12-11, 12:33:57 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:33:40 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=04:2a:e2:c6:49:5d;CM-QOS=1.1;CM-VER=3.0;
2024-12-11, 12:33:08 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:45:5a:d0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
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I'm also getting a new modem this weekend and went with a surfboard sb8200.
Thanks everyone for the help and input. It's much appreciated. Happy Holidays
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Re: Cm600 connection issues xfinity
Any Criticals, Errors or Warnings seen in the event logs needs to be reviewed and resolved by the ISP. Indicates a signal issue on the ISP line up to the modem.
Please post a copy and paste of the modems connection status log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-m...
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Re: Cm600 connection issues xfinity
Frequency start Value | |
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect. | |
|
Startup Procedure
Procedure | Status | Comment |
Acquire Downstream Channel | 459000000 Hz | Locked |
Connectivity State | OK | Operational |
Boot State | OK | Operational |
Security | Enable | BPI+ |
IP Provisioning Mode | Honor MDD | IPv6 only |
<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
Channel | Lock Status | Modulation | Channel ID | Frequency | Power | SNR | Correctables | Uncorrectables |
1 | Locked | QAM256 | 5 | 459000000 Hz | -0.1 dBmV | 42.5 dB | 0 | 0 |
2 | Locked | QAM256 | 22 | 561000000 Hz | 0.3 dBmV | 41.9 dB | 0 | 0 |
3 | Locked | QAM256 | 23 | 567000000 Hz | 0.4 dBmV | 42.1 dB | 0 | 0 |
4 | Locked | QAM256 | 24 | 573000000 Hz | 0.6 dBmV | 42.2 dB | 1 | 0 |
5 | Locked | QAM256 | 1 | 435000000 Hz | 0.4 dBmV | 42.4 dB | 0 | 0 |
6 | Locked | QAM256 | 2 | 441000000 Hz | -0.1 dBmV | 42.0 dB | 0 | 0 |
7 | Locked | QAM256 | 3 | 447000000 Hz | -0.7 dBmV | 41.8 dB | 0 | 0 |
8 | Locked | QAM256 | 4 | 453000000 Hz | 0.6 dBmV | 42.9 dB | 0 | 0 |
9 | Locked | QAM256 | 6 | 465000000 Hz | 0.4 dBmV | 42.8 dB | 0 | 0 |
10 | Locked | QAM256 | 7 | 471000000 Hz | 0.6 dBmV | 42.8 dB | 0 | 0 |
11 | Locked | QAM256 | 8 | 477000000 Hz | -0.4 dBmV | 42.0 dB | 0 | 0 |
12 | Locked | QAM256 | 9 | 483000000 Hz | 0.6 dBmV | 42.6 dB | 0 | 0 |
13 | Locked | QAM256 | 10 | 489000000 Hz | 0.1 dBmV | 42.3 dB | 0 | 0 |
14 | Locked | QAM256 | 11 | 495000000 Hz | -0.1 dBmV | 42.4 dB | 0 | 0 |
15 | Locked | QAM256 | 12 | 501000000 Hz | 0.7 dBmV | 43.0 dB | 0 | 0 |
16 | Locked | QAM256 | 13 | 507000000 Hz | 0.3 dBmV | 38.6 dB | 0 | 0 |
17 | Locked | QAM256 | 14 | 513000000 Hz | -0.4 dBmV | 42.4 dB | 0 | 0 |
18 | Locked | QAM256 | 15 | 519000000 Hz | -0.5 dBmV | 42.0 dB | 0 | 0 |
19 | Locked | QAM256 | 16 | 525000000 Hz | -1.0 dBmV | 41.9 dB | 0 | 0 |
20 | Locked | QAM256 | 17 | 531000000 Hz | -0.4 dBmV | 41.9 dB | 0 | 0 |
21 | Locked | QAM256 | 18 | 537000000 Hz | -0.6 dBmV | 41.9 dB | 0 | 0 |
22 | Locked | QAM256 | 19 | 543000000 Hz | -0.5 dBmV | 41.8 dB | 0 | 0 |
23 | Locked | QAM256 | 20 | 549000000 Hz | -0.1 dBmV | 41.9 dB | 0 | 0 |
24 | Locked | QAM256 | 21 | 555000000 Hz | -0.3 dBmV | 41.9 dB | 1 | 0 |
<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel | Lock Status | US Channel Type | Channel ID | Symbol Rate | Frequency | Power |
1 | Locked | ATDMA | 3 | 5120 Ksym/sec | 22800000 Hz | 57.0 dBmV |
2 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
3 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
4 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
5 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
6 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
7 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
8 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
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Re: Cm600 connection issues xfinity
Cable Connections data is good.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
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.
Start with removing any amplifiers, signal attenuators, or splitters from the coax.
From there check the line for kinks, damage, moisture in the line.
Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
https://highspeed.tips/docsis-events/
The CM600 is of older model so you may need to upgrade the modem at some point.
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Re: Cm600 connection issues xfinity
Your connection status sheet shows only one upstream bonded channel. I would expect at least four. That is an issue Xfinity should correct.
Your CM600 is an older DOCSIS 3.0 modem, I echo the recommendation from @FURRYe38 that you should consider replacement sometime soon.
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Re: Cm600 connection issues xfinity
Your cable connection is not good. At an upstream of 57dbmv, we'd expect your downstream to be pretty low. Probably in the -7.5 to -15dbmv. That high of an upstream indicates the modem has to send significant power just to reach the hub/cmts. And it tends to be reciprocal. So, if it's takes that much power for the modem to send data to the hub/cmts, it should have lower downstream values. Yours doesn't. It's sitting about 0 (ish). Something in the line is causing resistance one way (like specific attenuators or cable connection issues), or you're using an amplifier to boost a sketchy signal.
Back to checking the line for amplifiers or other issues because that isn't a good signal level. They need to be roughly representative of each other's values.
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Re: Cm600 connection issues xfinity
and @Kitsap is correct. You're coming up on end of life for the cm600. Xfinity is pushing docsis 3.1 devices for speed tiers.
Keep on eye on their mid-split list for the modems with the higher upstream. You don't think you need it until you have it and appreciate the faster uploads.
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I'm also getting a new modem this weekend and went with a surfboard sb8200.
Thanks everyone for the help and input. It's much appreciated. Happy Holidays
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