help with attbi - 3com "tailfin" - intermittent connectivity

help with attbi - 3com "tailfin" - intermittent connectivity

Post by davexne » Wed, 25 Jun 2003 11:58:05



Hello,
for about the last 7 days, I've been experiencing intermittent
service.  It's accessing the 'net at full speed for perhaps
5 - 10 minutes, then it hangs, I get the error beep from the modem,
and then it appears to attempt to recover.  Sometimes the service will
resume in a few minutes, sometimes not.  Rebooting the modem
manually recovers, but only for a short while.

The guy from Attbi/Comcast is coming to my house on Thursday
to take a look, but I was interested if any body had any
insight based on the log I have captured: (192.168.100.1):

                CM RESET REASON ID       2 0:0:2.0 1\1\1970 +0:0 ROOT
1 ********************************************************
3 0:0:3.0 1\1\1970 +0:0 cmmr 1    ***** CMM ***** Acquiring Freq
0739786900 Hz
4 0:0:4.0 1\1\1970 +0:0 bcmr 1
Downstream Information
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Tuner Freq    : 739.7869 MHz
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 CurFreqErr    : 000000
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Symbol Rate   : 5.056941 MHz
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Lock Threshold: 20.50 dB
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 SNR Value     : 29.53 dB
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 QAM mode      : 64
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Interleave Depth : 32,4,32
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 QAM and FEC locked
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Uncorrectable Errors: 0
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Downstream Power Level:   4.8
4 0:0:4.0 1\1\1970 +0:0 bcmr 1 Acquiring Time Sync
6 0:0:6.0 1\1\1970 +0:0 bcmr 1 Course sync check is valid
6 0:0:6.0 1\1\1970 +0:0 bcmr 1 Fine sync check is valid
7 0:0:7.0 1\1\1970 +0:0 cmmr 1 Upstream symbol rate:  2.560 MHz
7 0:0:7.0 1\1\1970 +0:0 cmmr 1 Upstream center frequency: 25.328 MHz
7 0:0:7.0 1\1\1970 +0:0 cmmr 1    UCD collection Completed; Select a
UCD
7 0:0:7.0 1\1\1970 +0:0 cmmr 1    CMM Primary SID updated: 0
7 0:0:7.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 06 ChgCnt: 1F
7 0:0:7.0 1\1\1970 +0:0 cmmr 1    ***** CMM ***** Start Broadcast
Ranging TS=00000C68
7 0:0:7.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 8.0 power level
8 0:0:8.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
8 0:0:8.0 1\1\1970 +0:0 cmmr 1  Setting power level to 16.0
8 0:0:8.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 16.0 power level
8 0:0:8.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
8 0:0:8.0 1\1\1970 +0:0 cmmr 1  Setting power level to 25.0
8 0:0:8.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 25.0 power level
8 0:0:8.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
8 0:0:8.0 1\1\1970 +0:0 cmmr 1  Setting power level to 33.0
9 0:0:9.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
9 0:0:9.0 1\1\1970 +0:0 cmmr 1  Setting power level to 41.8
9 0:0:9.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 41.8 power level
9 0:0:9.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
9 0:0:9.0 1\1\1970 +0:0 cmmr 1  Setting power level to 49.9
9 0:0:9.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 49.9 power level
9 0:0:9.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
9 0:0:9.0 1\1\1970 +0:0 cmmr 1  Setting power level to 58.0
10 0:0:10.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 58.0 power
level
 xxxxxxxxxxxxxxx
10 0:0:10.0 1\1\1970 +0:0 cmmr 1 sound_play_file error22.wav volume =
3
11 0:0:11.0 1\1\1970 +0:0 cmmr 1 Upstream symbol rate:  2.560 MHz
11 0:0:11.0 1\1\1970 +0:0 cmmr 1 Upstream center frequency: 25.328 MHz
11 0:0:11.0 1\1\1970 +0:0 cmmr 1    CMM Primary SID updated: 0
11 0:0:11.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 01 ChgCnt: 1F
11 0:0:11.0 1\1\1970 +0:0 cmmr 1  Setting power level to 8.0
11 0:0:11.0 1\1\1970 +0:0 cmmr 1    ***** CMM ***** Start Broadcast
Ranging TS=000012AA
11 0:0:11.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 8.0 power level
12 0:0:12.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
12 0:0:12.0 1\1\1970 +0:0 cmmr 1  Setting power level to 16.0
12 0:0:12.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 16.0 power
level
12 0:0:12.0 1\1\1970 +0:0 cmmr 1  Setting power level to 25.0
12 0:0:12.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 25.0 power
level
12 0:0:12.0 1\1\1970 +0:0 fdsp 1 sound_play_file connect22.wav volume
= 3
12 0:0:12.0 1\1\1970 +0:0 fdsp 1 Successfully added route to CPE
12 0:0:12.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
12 0:0:12.0 1\1\1970 +0:0 cmmr 1  Setting power level to 33.0
13 0:0:13.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 33.0 power
level
13 0:0:13.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
13 0:0:13.0 1\1\1970 +0:0 cmmr 1  Setting power level to 41.8
13 0:0:13.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 41.8 power
level
14 0:0:14.0 1\1\1970 +0:0 cmmr 1  Setting power level to 49.9
14 0:0:14.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 49.9 power
level
14 0:0:14.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
14 0:0:14.0 1\1\1970 +0:0 cmmr 1  Setting power level to 58.0
15 0:0:15.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 58.0 power
level
15 0:0:15.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
15 0:0:15.0 1\1\1970 +0:0 cmmr 1  Setting power level to 12.0
16 0:0:16.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 12.0 power
level
17 0:0:17.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
17 0:0:17.0 1\1\1970 +0:0 cmmr 1  Setting power level to 20.0
17 0:0:17.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
17 0:0:17.0 1\1\1970 +0:0 cmmr 1  Setting power level to 29.0
18 0:0:18.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 29.0 power
level
18 0:0:18.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
18 0:0:18.0 1\1\1970 +0:0 cmmr 1  Setting power level to 37.0
18 0:0:18.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 37.0 power
level
19 0:0:19.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
19 0:0:19.0 1\1\1970 +0:0 cmmr 1  Setting power level to 46.3
19 0:0:19.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 46.3 power
level
19 0:0:19.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
20 0:0:20.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 54.4 power
level
20 0:0:20.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
20 0:0:20.0 1\1\1970 +0:0 cmmr 1    Max random backoff reached -- OR
--
                        All Tx power levels have been exercised!
20 0:0:20.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 02 ChgCnt: 1F
20 0:0:20.0 1\1\1970 +0:0 cmmr 1 Upstream symbol rate:  2.560 MHz
20 0:0:20.0 1\1\1970 +0:0 cmmr 1 Upstream center frequency: 25.328 MHz
20 0:0:20.0 1\1\1970 +0:0 cmmr 1    CMM Primary SID updated: 0
20 0:0:20.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 02 ChgCnt: 1F
20 0:0:20.0 1\1\1970 +0:0 cmmr 1  Setting power level to 8.0
20 0:0:20.0 1\1\1970 +0:0 cmmr 1    ***** CMM ***** Start Broadcast
Ranging TS=0000207D
21 0:0:21.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
21 0:0:21.0 1\1\1970 +0:0 cmmr 1  Setting power level to 16.0
21 0:0:21.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 16.0 power
level
22 0:0:22.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
22 0:0:22.0 1\1\1970 +0:0 cmmr 1  Setting power level to 25.0
22 0:0:22.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 25.0 power
level
22 0:0:22.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
22 0:0:22.0 1\1\1970 +0:0 cmmr 1  Setting power level to 33.0
22 0:0:22.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 33.0 power
level
23 0:0:23.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
23 0:0:23.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 41.8 power
level
23 0:0:23.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
23 0:0:23.0 1\1\1970 +0:0 cmmr 1  Setting power level to 49.9
24 0:0:24.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 49.9 power
level
24 0:0:24.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
24 0:0:24.0 1\1\1970 +0:0 cmmr 1  Setting power level to 58.0
24 0:0:24.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 58.0 power
level
24 0:0:24.0 1\1\1970 +0:0 cmmr 1 sound_play_file error22.wav volume =
3
24 0:0:24.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 01 ChgCnt: 00
25 0:0:25.0 1\1\1970 +0:0 cmmr 1 Upstream symbol rate:  2.560 MHz
25 0:0:25.0 1\1\1970 +0:0 cmmr 1    CMM Primary SID updated: 0
25 0:0:25.0 1\1\1970 +0:0 cmmr 1 Prog UsChanId: 01 ChgCnt: 1F
25 0:0:25.0 1\1\1970 +0:0 cmmr 1  Setting power level to 8.0
25 0:0:25.0 1\1\1970 +0:0 cmmr 1    ***** CMM ***** Start Broadcast
Ranging TS=0000288F
25 0:0:25.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 8.0 power level
26 0:0:26.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
26 0:0:26.0 1\1\1970 +0:0 cmmr 1  Setting power level to 16.0
26 0:0:26.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 16.0 power
level
26 0:0:26.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
26 0:0:26.0 1\1\1970 +0:0 cmmr 1  Setting power level to 25.0
26 0:0:26.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
26 0:0:26.0 1\1\1970 +0:0 cmmr 1  Setting power level to 33.0
26 0:0:26.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 33.0 power
level
27 0:0:27.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
27 0:0:27.0 1\1\1970 +0:0 cmmr 1  Setting power level to 41.8
27 0:0:27.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 41.8 power
level
27 0:0:27.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
27 0:0:27.0 1\1\1970 +0:0 cmmr 1  Setting power level to 49.9
28 0:0:28.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 49.9 power
level
28 0:0:28.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
28 0:0:28.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 58.0 power
level
28 0:0:28.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
28 0:0:28.0 1\1\1970 +0:0 cmmr 1  Setting power level to 12.0
29 0:0:29.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 12.0 power
level
29 0:0:29.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
29 0:0:29.0 1\1\1970 +0:0 cmmr 1  Setting power level to 20.0
29 0:0:29.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 20.0 power
level
29 0:0:29.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
29 0:0:29.0 1\1\1970 +0:0 cmmr 1  Setting power level to 29.0
30 0:0:30.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 29.0 power
level
30 0:0:30.0 1\1\1970 +0:0 cmmr 1  Setting power level to 37.0
31 0:0:31.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 37.0 power
level
31 0:0:31.0 1\1\1970 +0:0 cmmr 1    DOCSIS T3 timeout!
31 0:0:31.0 1\1\1970 +0:0 cmmr 1  Setting power level to 46.3
32 0:0:32.0 1\1\1970 +0:0 cmmr 1 Range Request sent at 46.3 power
level
32 0:0:32.0 1\1\1970 +0:0 ...

read more »

 
 
 

help with attbi - 3com "tailfin" - intermittent connectivity

Post by Jerr » Wed, 25 Jun 2003 13:37:55


Just my 2cents:

Quote:> Tuner Freq    : 739.7869 MHz
> Lock Threshold: 20.50 dB
> SNR Value     : 29.53 dB
> Downstream Power Level:   4.8

4.8 digital signal, 15dB down from analog signal of approx. 19.8 -- TOO HIGH
Is this modem hooked up after a house amplifier? Looks to me like your
over-powering it.

Quote:> Setting power level to 58.0
> Range Request sent at 58.0 power level
>  xxxxxxxxxxxxxxx
> All Tx power levels have been exercised!
> mcns: power level adjust (1/4 dB) = 007
> Setting power level to 39.0
>     ***** CMM ***** Ranging Complete,
> Tx Power:      39.0
>    ***** CMM ***** MAC Registration Complete
> 36 1:57:11.0 6\24\2003 +6:0 cmmr 1 ********** START FORWARDING DONE|
> **********

>  There seems to be retries at different power levels, but I not
> sure what this indicates.
> I have added xxxxxxxxxx to the log at the point an error is
> acknowledged.
> Any info appreciated!
> Dave

Modem was maxing out on transmit power (can only do 60dB).
May have been due to an outage in your area. Ask tech if he/she has
knowledge of any.
I like to find the downstream SNR at 32dB, or more, with an analog signal
level of between 3 and 8dB on channel
3 at the modem. The modem should be on a clean line by itself, only one
splitter (or DC) and the ground block between the modem and the cable drop.
Also, check the AC wall outlet that the modem is attached to for proper
polarity and ground. ANY voltage on the neutral or ground wire will cause
the modem to reboot alot. I've come across hot grounds and miss-wired
outlets (or clipped grounding plugs) that play havoc with the modem, not to
mention the shock- and fire-hazard.
Jerry

 
 
 

help with attbi - 3com "tailfin" - intermittent connectivity

Post by davexne » Wed, 25 Jun 2003 14:24:17




Thanks for your comments -

>Just my 2cents:


>> Tuner Freq    : 739.7869 MHz
>> Lock Threshold: 20.50 dB
>> SNR Value     : 29.53 dB
>> Downstream Power Level:   4.8

>4.8 digital signal, 15dB down from analog signal of approx. 19.8 -- TOO HIGH
>Is this modem hooked up after a house amplifier? Looks to me like your
>over-powering it.

No - it's connected directly to the line coming from the outside
pole.
I don't have a splitter, as I am not connecting any TV's.
Quote:>> Setting power level to 58.0
>> Range Request sent at 58.0 power level
>>  xxxxxxxxxxxxxxx
>> All Tx power levels have been exercised!
>> mcns: power level adjust (1/4 dB) = 007
>> Setting power level to 39.0
>>     ***** CMM ***** Ranging Complete,
>> Tx Power:      39.0
>>    ***** CMM ***** MAC Registration Complete
>> 36 1:57:11.0 6\24\2003 +6:0 cmmr 1 ********** START FORWARDING DONE|
>> **********

>>  There seems to be retries at different power levels, but I not
>> sure what this indicates.
>> I have added xxxxxxxxxx to the log at the point an error is
>> acknowledged.
>> Any info appreciated!
>> Dave

>Modem was maxing out on transmit power (can only do 60dB).
>May have been due to an outage in your area. Ask tech if he/she has
>knowledge of any.

I spoke to the level 1 tech, she wasn't aware of any outages.
The only thing she could confirm was that it was indeed
"dropping" sigal (she could see from her end).
Then a few days later, did a "live chat" and they were not aware of
anything either.  Nor did they have a clue of what to do - that's
why they suggested sending a body.
Quote:>I like to find the downstream SNR at 32dB, or more, with an analog signal
>level of between 3 and 8dB on channel
>3 at the modem. The modem should be on a clean line by itself, only one
>splitter (or DC) and the ground block between the modem and the cable drop.
>Also, check the AC wall outlet that the modem is attached to for proper
>polarity and ground. ANY voltage on the neutral or ground wire will cause
>the modem to reboot alot. I've come across hot grounds and miss-wired
>outlets (or clipped grounding plugs) that play havoc with the modem, not to
>mention the shock- and fire-hazard.
>Jerry

Very interesting, I do have one of those cheap 3-prong testers.
Although since the power is supplied via 3com's small
DC transformer, it seems unlikely to me that this could affect it.
(Of course, I could be wrong)

Dave