07-18-2012 05:04 AM
Apparently, my Motorola sb 6120 has been having fits last night and one just now (e.g. 4:50-ish am EST). This is the weirdest (to me):
|Jan 01 1970 00:00:31||3-Critical||D05.0||TFTP failed - Request sent - No Response|
That one just occurred - the rest of the log are filled with Jan 01 entiries.
Is this "TFTP" something extraordinarily bad? Any advice, please?
Thanks in advance.
07-18-2012 05:42 AM
UPDATE: Just power-cycled modem, cleared cache/cookies and dns cache and ONLY ONE CHANNEL BONDED. Used to be two channels as of a month or so ago.
Is it Comcast with the issues, or just lucky me?
Thanks in advance.
07-18-2012 08:10 AM
07-18-2012 08:17 AM
Thanks, but now what do I need to do for the correct configuration file? Do I HAVE to call Comcast ? If so, any suggested verbage to tell them?
I'm noticing it is taking a-g-e-s to connect to anything on Comcast and my upload speed is like 87kb. Grrr.
07-18-2012 08:34 AM
07-18-2012 12:16 PM - edited 07-18-2012 12:21 PM
What do the modem's signal stats look like ? Try getting them here; http://192.168.100.1
Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.
Any type of RF signal, connection quality, upstream or downstream path impairment that causes the modem and the CC system (CMTS) to not be able to talk to / hear each other can cause this to occur. Out of spec signal stats and/or noise ingress are the typical offenders.
As far as the "single channel" that the modem is now connected to now, this can be due to the CMTS calling for a DCC (Dynamic Channel Change) where a bad (noisey or congested) channel gets disabled in favor of a cleaner channel to communicate on. This happens on the fly and can change again at any given moment.
07-18-2012 12:29 PM
Here are current modem stats. FWIW, can't even run ShaperProbe and the other 'speed' tests show 0.01 upload speed, lol. Comcast swapping modem tomorrow (hopefully). Comcast phone agent said she saw my modem not getting power frequently. THANKS FOR ANY OTHER ADVICE.
|Frequency||579000000 Hz||585000000 Hz||591000000 Hz||597000000 Hz|
|Signal to Noise Ratio||37 dB||37 dB||37 dB||37 dB|
|Power Level |
|4 dBmV||4 dBmV||4 dBmV||5 dBmV|
|Ranging Service ID||194|
|Symbol Rate||5.120 Msym/sec|
|Power Level||42 dBmV|
|Upstream Modulation|| QPSK|
07-18-2012 12:33 PM
The stats as read at the modem level at that moment in time were o/k. But there are two additional signal stats which can't be read at the modem level. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.
They are the 'Upstream Receive Power Level' and the 'Upstream uSNR' (upstream Signal To Noise Ratio). Both of these are as equally important in diagnosing connectivity issues as are the modem's stats.
You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -10dB to +10dB with 0dB being in the middle and perfect.
The Upstream SNR should be least 30dB, and the higher it is the better. You could have a noise ingress issue in the upstream channel/s only
07-19-2012 11:13 AM
Comcast tech grudgingly (!!) replaced my leased s/b 6120 with an Arris. Would someone here kindly look at my modem power levels below and advise if they are okay, please. Also, is this Arris WBM760a actually DOCSIS 3.0 ? (The tech was really surly so not sure if I should believe him.)
THANKS IN ADVANCE ..!
|Downstream 1||60||597.00 MHz||1.73 dBmV||37.09 dB||256QAM||6603302||0||0|
|Downstream 2||57||579.00 MHz||1.62 dBmV||37.09 dB||256QAM||6322512||0||0|
|Downstream 3||58||585.00 MHz||1.33 dBmV||37.09 dB||256QAM||6992038||0||0|
|Downstream 4||59||591.00 MHz||1.28 dBmV||36.84 dB||256QAM||5735372||0||0|
|Reset FEC Counters|
|UCID||Freq||Power||Channel Type||Symbol Rate||Modulation|
|Upstream 1||2||27.90 MHz||42.00 dBmV||DOCSIS2.0 (ATDMA)||5120 kSym/s||64QAM|
07-19-2012 11:37 AM
Thanks, EG .. you "guys" here are The Best.
Appreciate you having a look at power levels. New modem, new things to worry about :-)
07-20-2012 03:34 PM
Yes that is indeed good, but I will add that a reboot erases the previous data and starts the counters going again, so the length of the time period that these errors are being recorded needs to be factored in.
07-21-2012 08:09 AM
Help again - please ...! This new Arris has dropped in and out 3x since 2 a.m. NOW I have 3 upload channels (what happened to #2?) and lots of uncorrectables.
WORSE, when I was directly connected I got directed to a Comcast sign up page because the tech supposedly didn't register my modem correctly?
|Downstream 1||60||597.00 MHz||0.93 dBmV||37.09 dB||256QAM||19937695||0||0|
|Downstream 2||57||579.00 MHz||1.09 dBmV||37.09 dB||256QAM||18680789||0||0|
|Downstream 3||58||585.00 MHz||0.81 dBmV||37.09 dB||256QAM||18282113||13||592|
|Downstream 4||59||591.00 MHz||0.83 dBmV||36.84 dB||256QAM||17981632||47||647|
Upstream 1 2 27.90 MHz 42.00 dBmV DOCSIS2.0 (ATDMA) 5120 kSym/s 64QAM
Upstream 3 1 34.80 MHz 42.50 dBmV DOCSIS2.0 (ATDMA) 5120 kSym/s 64QAM
Upstream 4 3 22.60 MHz 41.50 dBmV DOCSIS1.x (TDMA) 2560 kSym/s 16QAM
07-21-2012 10:53 AM
You signals are fine and there is nothing wrong with having three bonded upstreams now unless they are noisey. Seems that the modem may have went down at that time due to them upgrading the upstream. The overnight hours are their maintenance window. Not much else that we can do for you here, you need to call this in.
07-21-2012 10:56 AM
Thanks. Sounds like I don't need to call then if levels not noisy ?
Really DO apologize if being a worrisome pest (beats cleaning litter trays). *sends brownies as Thank You*
07-21-2012 11:06 AM
No worries. Only they can see from their end if the upstreams are noisey. See what happens over the next couple of days as the bugs typically need to be worked out. If you still have a problem then you need to call in and report it.
©2011 Comcast | Investor Relations | Press Room | Corporate Blog | Privacy Statement | Visitor Agreement | Comcast.com Feedback | Site Map