DHCP FAILED / NO RANGING (BFECMU10)

[joejoefta2]

Is there an thing I can do to prevent the modem for changing downstream channel? Several times in a day and sometime it will just rng-rsp untill it locks onto a channel.

Here is what I get from serial output:
===> Entry already exists.
Scanning DS Channel at 747000000 Hz...
Found carrier at 747000000 Hz!
Signal quality = 29.6 dB SNR

RNG-RSP Adj: tim=-11 power=20 freq=0 Stat=Continue
5.1.2 to agent
===> Entry already exists.
Scanning DS Channel at 717000000 Hz...
dB SNR
t=Continue
xists.
Scanning DS Channel at 735000000 Hz...
Found carrier at 735000000 Hz!
Signal quality = 29.7 dB SNR
ue

RNG-RSP Adj: tim=0 power=19 freq=0 Stat=Success
Enabling network access for all CPE ports.
BcmCmDocsisStatusEventCodes::kCmIsOperational
BcmCmDocsisStatusEventCodes::kCmIsOperational
VendorCtrl: HFC up
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
Found carrier at 723000000 Hz!
Signal quality = 28.9 dB SNR
=Success
Enabling network access for all CPE ports.
BcmCmDocsisStatusEventCodes::kCmIsOperational
BcmCmDocsisStatusEventCodes::kCmIsOperational
VendorCtrl: HFC up
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.
===> WARNING: Failed to register TabularMibBridge 1.3.6.1.2.1.85.1.2 to agent
===> Entry already exists.

This is from modem log:

2012-11-09 13:03:31 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 13:00:14 critical No Ranging Response received - T3 time-out
2012-11-09 13:00:07 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:56:45 critical No Ranging Response received - T3 time-out
2012-11-09 12:56:41 critical SYNC Timing Synchronization failure - Failed to acquire FEC framing
2012-11-09 12:56:36 critical SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2012-11-09 12:56:24 critical No UCD's Received - Timeout
2012-11-09 12:56:12 critical No UCD's Received - Timeout
2012-11-09 12:55:15 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:51:56 critical No Ranging Response received - T3 time-out
2012-11-09 12:51:50 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:48:35 critical No Ranging Response received - T3 time-out
2012-11-09 12:48:30 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:45:15 critical No Ranging Response received - T3 time-out
2012-11-09 12:45:12 critical Init RANGING Critical Ranging Request Retries exhausted
2012-11-09 12:45:12 critical No Ranging Response received - T3 time-out
2012-11-09 12:41:15 critical No UCD's Received - Timeout
2012-11-09 12:38:09 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:34:53 critical No Ranging Response received - T3 time-out
2012-11-09 12:34:50 critical Init RANGING Critical Ranging Request Retries exhausted
2012-11-09 12:34:50 critical No Ranging Response received - T3 time-out
2012-11-09 12:31:47 critical DHCP FAILED - Discover sent, no offer received
2012-11-09 12:28:31 critical No Ranging Response received - T3 time-out

[ABMJR]

fix your rf issues 1st

[joejoefta2]

Are you referring to cable connection into the modem?

[ABMJR]

Found carrier at 723000000 Hz!
Signal quality = 28.9 dB SNR
=Success

min SNR is 30 Db> or greater

thus the channel change

[joejoefta2]

I guess all the splitters before the cable modem doesn't help. Let me relocate the modem before the splitters to see if it helps.

[joejoefta2]

Got it to 31.6dB. Hopefully this will prevent it from changing DS channel.

Symbol Rate 5360.537 Ksym/sec
Downstream Power -7.9 dBmV
SNR 31.6 dB