A71
Spectator

Modem Random Reboots Daily

Since the week of Memorial Day, I have had pretty much daily, sometimes multiple times a day, internet drops.  They are random, and only lasts for a few minutes.  I normally would just ignore this and deal with it, but, the drops are now happening during the normal work day hours, and, I work from home, so this is cutting into my productive time. I managed to get into the modem logs and saw this:

 

Upstream

UCID
Freq
Power
Channel Type
Symbol Rate
Modulation
Upstream 1
1
17.80 MHz
57.00 dBmV
DOCSIS2.0 (ATDMA)
5120 kSym/s
64QAM

 

Instead of the normal 4 upstream channels I was used to seeing, with power levels in the mid 40's, I just have 1 channel with power levels in the high 50's.

 

Downstream

DCID
Freq
Power
SNR
Modulation
Octets
Correcteds
Uncorrectables
Downstream 1
9
489.00 MHz
6.30 dBmV
40.95 dB
256QAM
91258287
0
0
Downstream 2
2
447.00 MHz
6.00 dBmV
40.95 dB
256QAM
19737863
10
0
Downstream 3
3
453.00 MHz
6.20 dBmV
43.38 dB
256QAM
17329574
0
0
Downstream 4
4
459.00 MHz
6.20 dBmV
43.38 dB
256QAM
23531285
15
0
Downstream 5
5
465.00 MHz
6.10 dBmV
40.95 dB
256QAM
22039462
0
0
Downstream 6
6
471.00 MHz
6.20 dBmV
43.38 dB
256QAM
21222292
0
0
Downstream 7
7
477.00 MHz
6.00 dBmV
40.95 dB
256QAM
17997030
0
0
Downstream 8
8
483.00 MHz
5.90 dBmV
40.95 dB
256QAM
17596857
0
0
Downstream 9
1
435.00 MHz
5.80 dBmV
40.95 dB
256QAM
22226220
0
0
Downstream 10
10
495.00 MHz
5.90 dBmV
43.38 dB
256QAM
18347905
0
0
Downstream 11
11
501.00 MHz
6.10 dBmV
40.95 dB
256QAM
18400832
0
0
Downstream 12
12
507.00 MHz
5.70 dBmV
40.95 dB
256QAM
17303171
0
0
Downstream 13
13
513.00 MHz
5.60 dBmV
40.37 dB
256QAM
17118242
0
0
Downstream 14
14
519.00 MHz
5.40 dBmV
40.95 dB
256QAM
17526013
0
0
Downstream 15
15
525.00 MHz
5.80 dBmV
40.95 dB
256QAM
18331567
0
0
Downstream 16
16
531.00 MHz
5.60 dBmV
40.95 dB
256QAM
18573675
0
0
Downstream 17
17
537.00 MHz
5.80 dBmV
40.95 dB
256QAM
20150201
0
0
Downstream 18
18
543.00 MHz
5.40 dBmV
40.37 dB
256QAM
20039437
0
0
Downstream 19
19
549.00 MHz
5.30 dBmV
40.95 dB
256QAM
16810647
0
0
Downstream 20
20
555.00 MHz
5.20 dBmV
40.37 dB
256QAM
18324217
0
0
Downstream 21
21
561.00 MHz
5.00 dBmV
40.37 dB
256QAM
16735119
0
0
Downstream 22
22
567.00 MHz
5.00 dBmV
40.37 dB
256QAM
22479751
0
0
Downstream 23
23
573.00 MHz
5.10 dBmV
40.95 dB
256QAM
22069007
0
0
Downstream 24
24
579.00 MHz
5.00 dBmV
40.37 dB
256QAM
20770115
0
0

 

 

My modem is fairly new, Arris, and all of the cables and connections in the house are fine; I do have a splitter (which I cannot get rid of), and a tech earlier this year installed a power inserter, I think that is what it is called, because my upstream speed was so high, and after installing it, the upstream power went down to the low 40's,  but its back up again.  Before I call for a tech visit, can someone check out this log for me?  I'm not very techie, so not sure exactly what to look for.

10 REPLIES 10
Community Manager

Re: Modem Random Reboots Daily


Upstream

UCID
Freq
Power
Channel Type
Symbol Rate
Modulation
Upstream 1
1
17.80 MHz
57.00 dBmV
DOCSIS2.0 (ATDMA)
5120 kSym/s
64QAM


 

@A71 , 

 

There is definitely something not right with this modem.  As well, I deleted the Downstream portion you posted for privacy as it included a MAC address.  For the upstream, it is showing one channel and DOCSIS 2.0.  Please start by trying a pinhole reset of the modem.  This will reset all settings, so you will need to reconfigure any settings on the modem, including  the wireless network.  If the issue is not resolved, please contact us directly by private message so we can troubleshoot further.  

 

Proven Sharer

Re: Modem Random Reboots Daily

DOCSIS 2.0 is normal on the uplink side, but only one channel running at +57 dBmV definitely is not.  There is a Spectrum network problem on the upstream side somewhere between the modem and the CMTS.  The subscriber's comment about a tech adding a power inserter is curious since there was no mention of an amplifier.  User needs a site tech visit to perform a signal level check and investigate the newly added "power inserter" device. 

A71
Spectator

Re: Modem Random Reboots Daily

Just did the pin hole reset, and will wait and see if helps. If not, I might switch from the Spectrum modem to one of my own.
Community Manager

Re: Modem Random Reboots Daily

 


@karlbeckman wrote:

DOCSIS 2.0 is normal on the uplink side, but only one channel running at +57 dBmV definitely is not.  There is a Spectrum network problem on the upstream side somewhere between the modem and the CMTS.  


Thanks, @karlbeckman.  The DOCSIS 2.0  stuck out and I was thinking the two were related.  I apprecitate the explanation.  

Community Manager

Re: Modem Random Reboots Daily

@A71 , 

 

Based on the explanation from @karlbeckman , I'd recommend a service call as well.  Let us know if we can assist with setting one up for you.  

A71
Spectator

Re: Modem Random Reboots Daily

The pin hole reset worked temporarily.  The modem was fine all day, had 4 upstream channels, with power levels at 47.  Just a few minutes ago, same issue came up, down to 1 upstream channel, with 57 dbmv power level.  Did the pin hole reset again, but no luck, still just the 1 channel. I'll have to set up a service call and see when I can get a tech visit. Thanks for the help.

Proven Sharer

Re: Modem Random Reboots Daily

Check your in-house cabling & connectors one more time (just to avoid possible embarrassment), then schedule that service call now.  Something on Spectrum's network is intermittent, causing failure of the return signal heading upstream.  Could be a broken wire or a loose connector, or even a tap housing filling with water during a rainstorm.  For internet speeds up to 100 Mbps your modem needs 8 downstream and 4 upstream data channels . 

Sharer

Re: Modem Random Reboots Daily

@karlbeckman brought up an unfortunately fairly common point... weather is a far more common culprit than many realize. Especially in older neighborhoods.

And it isn't just the variations in resistance because of hotter and colder seasons. Some of the pedestals can wind up taking on water, which can send signalling awol.

We suffer that in our neighborhood often. We have a sort of "tombstone" setup, where the hrdware is installed close to the ground, and there is a big plastic cover that drops on top of it. The casing doesn't seal properly, and it has been there so long the ground has risen up a bit so there isn't much height left to the surround. Doesn't take much heavy rainfall to "flood" the install--and we are in hurricane season now, which means lots of rain in our market.

May want to "eyeball" the outside infrastructure to see if it looks like a similar scenario for you. Even something like water pooling where a cable runs can present problems. May need to put some countermeasures in place to help direct water away from potentially vulnerable components.
A71
Spectator

Re: Modem Random Reboots Daily

After still having dropped connections, I went ahead and exchanged the modem for another Spectrum one, and they gave me one of the Spectrum routers.  So far, so good.  Now, I just need to figure out how to get to the modem logs to check on the upstream and downstream channels, just in case I have the issue again. The last modem I had, checking the logs was easy, this new one, not so much.