Over the past 4 days, have had more frequent outages. Called Xfinity 3 times, and Netgear 4 times. Comcast said things looked good to them, and that they were unable to send a tech out due to pandemic here (understandable--we're bad now). Netgear had me do multiple interventions, and is sending me out a new modem (cm7800 nighthawk), but they aren't sure what's up. My modem has worked fine for 2 months. However, no one is able to tell me if it's the cable signal or the modem. Can you tell from the modem log? I tried to educate myself, but I cannot get an answer ("dirty signal upstream?" vs modem issue). Here is a log of a recent interruption (reverse time order). Thanks for any help...
2020-07-05, 14:53:18
Warning (5)
MDD message timeout;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:53:03
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:53:02
Warning (5)
Dynamic Range Window violation
2020-07-05, 14:53:02
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
Time Not Established
Notice (6)
Honoring MDD; IP provisioning mode = IPv6
Time Not Established
Critical (3)
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:50:24
Critical (3)
Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:50:24
Critical (3)
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:48:34
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:48:14
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:48:02
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:48:00
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:54
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:42
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:39
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:34
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:09
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:07
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:47:00
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:46:58
Critical (3)
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
2020-07-05, 14:46:22
Critical (3)
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=bc:a5:11:89:85:7c;CMTS-MAC=00:9e:1e:59:0b:20;CM-QOS=1.1;CM-VER=3.1;
Please also post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.
Thanks for the reply. The Netgear folks had me chack last week. The range was -0.1 to about 1.9. They said that was fine.
However, this AM when it went out, things were different. I checked and saw upstream and downstream were all 0.
Here was part of the log from the most recent outage (from a screenshot):
[admin login] from source 192.168.0.4, Mon, Jul 06, 2020 14:55:12
[Internet disconnected] Mon, Jul 06, 2020 14:53:52
[admin login] from source 192.168.0.4, Mon, Jul 06, 2020 14:53:42
[DHCP IP: (192.168.0.3)] to MAC address 00:18:61:28:cc:ab, Mon, Jul 06, 2020 14:52:55
[DoS attack: Echo char gen] from source: 83.97.20.35, port 58136, Mon, Jul 06, 2020 14:20:56
[DHCP IP: (192.168.0.15)] to MAC address 18:55:e3:77:1f:a7, Mon, Jul 06, 2020 13:51:11
[DHCP IP: (192.168.0.10)] to MAC address 18:55:e3:65:e3:21, Mon, Jul 06, 2020 13:46:17
[DoS attack: Echo char gen] from source: 52.73.169.169, port 51121, Mon, Jul 06, 2020 12:16:32
[DoS attack: Echo char gen] from source: 83.97.20.35, port 57532, Mon, Jul 06, 2020 09:27:41
[DoS attack: UDP Scan] from source: 202.115.254.100, port 59111, Mon, Jul 06, 2020 08:44:25
[DoS attack: Echo char gen] from source: 80.82.77.139, port 29921, Mon, Jul 06, 2020 08:06:33
[DoS attack: Echo char gen] from source: 172.104.7.170, port 40602, Mon, Jul 06, 2020 08:03:32
[DoS attack: UDP Scan] from source: 109.123.117.247, port 19, Mon, Jul 06, 2020 03:44:16
[DoS attack: UDP Scan] from source: 71.6.233.146, port 17, Mon, Jul 06, 2020 03:12:16
[DHCP IP: (192.168.0.18)] to MAC address 74:54:7d:ff:b7:10, Mon, Jul 06, 2020 01:50:41
[DoS attack: Echo char gen] from source: 184.105.139.101, port 49077, Mon, Jul 06, 2020 01:20:17
[DoS attack: Echo char gen] from source: 146.88.240.4, port 56517, Mon, Jul 06, 2020 00:32:55
Also, everytime there's an outage, I reboot the modem and it comes back (at least for a while). Does this mean it's the modem/router, or is a bad or dirty data stream/signal from the ISP?
Would you please post a screenshot or paste the text of the entire signal status page for us to see.
Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.
It won't let me upload pics...here is the data:
downstream: power range -1.7 to +1.7 dBmV (channel 21-28 is all 0). SNR all 38.3-38.8 dB
upstream: power: 34.5-37.3 dBmV (channels 6-8 are not locked, and 0 power)
Thanks!