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DHCP help please

Regular Visitor

DHCP help please

Hello, read a few posts in here that seem to relate to my issue and @ComcastChe sounds like the goto guru. If you're out there and see this please contact me and let me know what info you need from me to help diagnose. Thank you in advance.

Problem has existed going on 3 weeks now and calliing customer service has proven to be futile. The one time I actually thought i was going to get transferred to tech resulted in the wrong department and then disconnected upon second transfer.

Asus router, error messge states 'DHCP failure contact your ISP provider' This started about  3 weeks ago after a windstorm in my area. Lost modem connectivity and wouldn't comeback so puchased another one. Worked for about a week then issues started again with modem constantly resetting.  Bought a different modem and seemed to work for a couple of days and now same issue again. Don't know if I have 2 problems or if they're connected but, if my flow goes modem into laptop i have internet but if i try to go modem into router then failure. Also, not sure if the storm impacted or exacerbated anything as I had noticed my internet connection resetting pretty regularly in the early morning hours prior to the storm which while aggravating, always returned within a few minutes.

I have checkd all my internal wiring and connections and do not have any splitters. When I sign into the modem admin (arris sb6190) this is the info on the status page:

Acquire Downstream Channel Locked
Connectivity StateOKOperational
Boot StateOKOperational
Configuration FileOK 
DOCSIS Network Access EnabledAllowed 


Downstream Bonded Channels
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectedUncorrectables
1Locked256QAM13531.00 MHz-1.80 dBmV38.61 dB00
2Locked256QAM9507.00 MHz-2.10 dBmV38.98 dB00
3Locked256QAM10513.00 MHz-2.50 dBmV38.61 dB00
4Locked256QAM11519.00 MHz-2.60 dBmV38.61 dB00
5Locked256QAM12525.00 MHz-2.40 dBmV37.64 dB00
6Locked256QAM14537.00 MHz-1.90 dBmV38.61 dB10
7Locked256QAM15543.00 MHz-1.80 dBmV38.61 dB00
8Locked256QAM16549.00 MHz-2.20 dBmV38.61 dB130
9Locked256QAM17555.00 MHz-2.30 dBmV38.61 dB10
10Locked256QAM18561.00 MHz-2.10 dBmV38.61 dB00
11Locked256QAM19567.00 MHz-1.90 dBmV38.61 dB70
12Locked256QAM20573.00 MHz-1.70 dBmV38.61 dB80
13Locked256QAM21579.00 MHz-1.70 dBmV38.61 dB00
14Locked256QAM22585.00 MHz-1.80 dBmV38.61 dB00
15Locked256QAM23591.00 MHz-1.90 dBmV38.61 dB00
16Locked256QAM24597.00 MHz-1.40 dBmV38.61 dB10
17Locked256QAM25603.00 MHz-1.10 dBmV38.98 dB00
18Locked256QAM26609.00 MHz-1.20 dBmV38.98 dB00
19Locked256QAM27615.00 MHz-1.80 dBmV38.61 dB60
20Locked256QAM28621.00 MHz-2.20 dBmV38.98 dB00
21Locked256QAM29627.00 MHz-2.00 dBmV38.61 dB50
22Locked256QAM30633.00 MHz-2.00 dBmV38.61 dB30
23Locked256QAM31639.00 MHz-1.00 dBmV38.61 dB130
24Locked256QAM32645.00 MHz-0.70 dBmV38.61 dB00
25Locked256QAM33651.00 MHz-0.80 dBmV38.60 dB00
26Locked256QAM34657.00 MHz-1.00 dBmV38.60 dB10
27Locked256QAM35663.00 MHz-0.80 dBmV38.60 dB00
28Locked256QAM36669.00 MHz-1.10 dBmV38.60 dB00
29Locked256QAM37675.00 MHz-1.00 dBmV38.60 dB00
30Locked256QAM38681.00 MHz-1.30 dBmV38.20 dB10
31Locked256QAM39687.00 MHz-1.50 dBmV38.20 dB10
32Locked256QAM40693.00 MHz-1.30 dBmV38.60 dB00


Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
2LockedATDMA25120 kSym/s30.10 MHz57.00 dBmV


Current System Time: Thu Oct 22 23:00:24 2020


The modem event log lists the folllowing:


Thu Oct 22 22:11:17 20206TLV-11 - unrecognized OID;CM-MAC=98:f7:81:56:3e:ad;CMTS-MAC=cc:8e:71:68:1b:24;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 22 22:11:35 20204TCS Fail on all Upstream Channels;CM-MAC=98:f7:81:56:3e:ad;CMTS-MAC=cc:8e:71:68:1b:24;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 22 22:11:35 20203Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=98:f7:81:56:3e:ad;CMTS-MAC=cc:8e:71:68:1b:24;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 22 22:11:36 20203No Ranging Response received - T3 time-out;CM-MAC=98:f7:81:56:3e:ad;CMTS-MAC=cc:8e:71:68:1b:24;CM-QOS=1.1;CM-VER=3.0;


I have the 600 internet service only, the arris modem and an asus router (RT-N66R)


Thank you for any help.


Re: DHCP help please

The upstream power is too high / out of spec. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels (you only have one. Should be 4-5).

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.

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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Regular Visitor

Re: DHCP help please

Thank you for your response.
After searching info on the net regarding upstream power levels, it would appear I have 2 problems. As I mentioned in my original post, I do not have any splitters, so I am going to hook the modem up directly to where the signal enters the house and get an upstream power level from that point.


In regards to the DHCP issue, I recall reading a post where @ComcastChe was able to assist another member with reprovisioning the boot file? Apologies if I'm not saying it correctly but as I gather this is different from the standard reset signal Comcast sends out.

If anyone is available to assist and offer input into the DHCP issue I would be most appreciative. Thank you.


Re: DHCP help please

Get the upstream power fixed, that random DHCP error may disappear. YMMV.


Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.
Good luck !

I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!