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Internet and voice go out for hours at a time - critical errors in modem log

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Frequent Visitor

Internet and voice go out for hours at a time - critical errors in modem log

As the subject says, internet and voice go out for hours at a time, sometimes 12+ hours like last night (went out around 6pm, came back 7am). I've about had it. I've had technicians out three times, including a supervisor, and the issue I'm having still isn't fixed and they can't find anything wrong.

The lines inside and out - from the box on the street, to the modem in my living room - have been replaced. I cut out our router and just use just the modem (XB6 - replaced twice by technicians) as a router now. Disconnected all non-essential ethernet devices and just have one desktop connected now, which I did unplug while experiencing these outages and nothing changed even after unplugging the modem for 30 seconds (supervisor technician said it could be feedback caused by ethernet cables or devices, that's why I cut out all non-essential ones).

Comcast claims everything on their end is fine - clearly it isn't. There are multiple people posting about this issue, latest one besides me is from yesterday, seen here: https://forums.xfinity.com/t5/Your-Home-Network/XB6-Gateway-keeps-dropping-connection-throughout-day... we have the same errors in our modem's error log which I'll post below.

Before you ask, here's the downstream and upstream levels while internet and voice were out:

Downstream
Channel Bonding Value
Index
25
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
26
27
28
29
30
31
32
0
 
Lock Status
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
Locked
NotLocked
Locked
Frequency
603000000
459000000
465000000
471000000
477000000
483000000
489000000
495000000
501000000
507000000
513000000
519000000
525000000
531000000
537000000
543000000
549000000
555000000
561000000
567000000
573000000
579000000
585000000
591000000
597000000
609000000
615000000
621000000
627000000
633000000
639000000
645000000
 
641600000
SNR
40.366287
40.946209
40.366287
40.366287
40.366287
40.366287
40.946209
40.366287
40.946209
40.366287
40.946209
40.946209
40.946209
40.366287
40.366287
40.946209
40.366287
40.946209
40.366287
40.946209
40.946209
40.366287
40.366287
40.366287
40.946209
40.366287
40.946209
40.366287
40.366287
40.366287
40.946209
40.366287
 
NA
Power Level
6.900002
6.400002
6.199997
6.199997
5.800003
5.699997
6.099998
6.099998
6.199997
6.099998
6.099998
6.300003
6.300003
6.099998
6.199997
6.300003
6.599998
6.599998
6.599998
6.699997
6.800003
7.000000
7.000000
6.900002
7.099998
7.000000
6.699997
6.599998
6.500000
6.199997
6.300003
5.900002
 
NA
Modulation
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
QAM256
UNSUPPORTED
OFDM

 

Upstream
Channel Bonding Value
Index
1
2
3
4
Lock Status
Locked
Locked
Locked
Locked
Frequency
30100000
17300000
23700000
36500000
Symbol Rate
5120 KSym/sec
5120 KSym/sec
5120 KSym/sec
5120 KSym/sec
Power Level
33.020599
32.520599
32.520599
33.020599
Modulation
64QAM
64QAM
64QAM
64QAM
Channel Type
US_TYPE_ATDMA
US_TYPE_ATDMA
US_TYPE_ATDMA
US_TYPE_ATDMA


Here are the the last few hours of various critical errors in the modem's log that show up while internet and voice are out (pastebin link as there are too many to post here): https://pastebin.com/UU4dMdjq

I will post a select few so people searching for these errors can find this thread:

DHCPv4[8303]: 72001008-DHCPv4 - No Offer or Ack Received 28 times
DHCPv4[8303]: 72001003-DHCPv4 Provision - 4 Retries Attempted. Last attempted at Fri Apr 3 10:58:30 2020
ti_dhcp6c[11122]: 72001011-DHCPv6 - Missing Required Option 24
ti_dhcp6c[11122]: 72001011-DHCPv6 - Missing Required Option 82
ti_dhcp6c[11122]: 72001014-DHCPv6 Failed - No Address Available
ti_dhcp6c[11122]: 72001015-DHCPv6 Failed - No Prefix Available
ti_dhcp6c[4705]: 72001004-DHCPv6 Provision - 13 Retries Attempted with Last attempt at Fri Apr 3 10:48:05 2020
ti_dhcp6c[4705]: 72001009-DHCPv6 - No Advertise or Reply Received 4 times

Anyone out there able to help?

Edit: here are firewall messages on the modem that seem to showcase the issue as well.

FW.IPv6 INPUT drop , 193 Attempts, 2020/4/07 15:51:43
FW.IPv6 FORWARD drop , 907 Attempts, 2020/4/07 14:52:37
FW.WANATTACK DROP , 104 Attempts, 2020/4/07 03:20:10

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Frequent Visitor

Re: Internet and voice go out for hours at a time - critical errors in modem log

Still happening to me, is anyone able to help?
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Frequent Visitor

Re: Internet and voice go out for hours at a time - critical errors in modem log

Edited the original post to include firewall entries that seem relevant.