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started unicast maintenance ranging - no response received

Regular Visitor

started unicast maintenance ranging - no response received

Hoping to get someone to look at my stats and offer suggestions. I'm getting "started unicast maintenance ranging - no response received" a few times per day and it seems to be increasing. I have an Arris SB8200. Below is an example of the error and the stats once the modem reconnected.

 

8-7-2018, 14:49:2

Critical(3)

"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:da:f9:16:41:15;CMTS-MAC=00:01:5c:a5:f2:65;CM-QOS=1.1;CM-VER=3.1;"

 

 

 

Connection

The status listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem.

Startup Procedure

Procedure

Status

Comment

Acquire Downstream Channel

663000000 Hz

Locked

Connectivity State

OK

Operational

Boot State

OK

Operational

Configuration File

OK

 

Security

Enabled

BPI+

DOCSIS Network Access Enabled

Allowed

 

 

Downstream Bonded Channels

Channel ID

Lock Status

Modulation

Frequency

Power

SNR/MER

Corrected

Uncorrectables

 

30

Locked

QAM256

663000000 Hz

-4.1 dBmV

37.8 dB

0

0

 

1

Locked

QAM256

489000000 Hz

-1.7 dBmV

39.4 dB

0

0

 

2

Locked

QAM256

495000000 Hz

-1.7 dBmV

39.3 dB

0

0

 

3

Locked

QAM256

501000000 Hz

-1.7 dBmV

39.0 dB

0

0

 

4

Locked

QAM256

507000000 Hz

-2.0 dBmV

39.1 dB

0

0

 

5

Locked

QAM256

513000000 Hz

-2.1 dBmV

38.9 dB

0

0

 

6

Locked

QAM256

519000000 Hz

-2.0 dBmV

39.1 dB

0

0

 

7

Locked

QAM256

525000000 Hz

-2.0 dBmV

39.2 dB

0

0

 

8

Locked

QAM256

531000000 Hz

-2.1 dBmV

39.1 dB

0

0

 

9

Locked

QAM256

537000000 Hz

-2.4 dBmV

39.0 dB

0

0

 

10

Locked

QAM256

543000000 Hz

-2.7 dBmV

38.8 dB

0

0

 

11

Locked

QAM256

549000000 Hz

-2.5 dBmV

38.9 dB

0

0

 

12

Locked

QAM256

555000000 Hz

-2.5 dBmV

38.9 dB

0

0

 

13

Locked

QAM256

561000000 Hz

-2.4 dBmV

38.9 dB

0

0

 

14

Locked

QAM256

567000000 Hz

-2.2 dBmV

39.2 dB

0

0

 

15

Locked

QAM256

573000000 Hz

-2.2 dBmV

39.2 dB

0

0

 

16

Locked

QAM256

579000000 Hz

-2.1 dBmV

39.3 dB

0

0

 

17

Locked

QAM256

585000000 Hz

-2.4 dBmV

39.1 dB

0

0

 

18

Locked

QAM256

591000000 Hz

-2.6 dBmV

39.0 dB

0

0

 

19

Locked

QAM256

597000000 Hz

-3.3 dBmV

38.5 dB

0

0

 

20

Locked

QAM256

603000000 Hz

-3.2 dBmV

38.5 dB

0

0

 

21

Locked

QAM256

609000000 Hz

-3.3 dBmV

38.5 dB

0

0

 

22

Locked

QAM256

615000000 Hz

-3.3 dBmV

38.4 dB

0

0

 

23

Locked

QAM256

621000000 Hz

-3.6 dBmV

38.2 dB

0

0

 

24

Locked

QAM256

627000000 Hz

-3.7 dBmV

38.2 dB

0

0

 

25

Locked

QAM256

633000000 Hz

-3.7 dBmV

38.1 dB

0

0

 

26

Locked

QAM256

639000000 Hz

-3.8 dBmV

38.3 dB

0

0

 

27

Locked

QAM256

645000000 Hz

-3.7 dBmV

38.2 dB

0

0

 

28

Locked

QAM256

651000000 Hz

-3.9 dBmV

38.0 dB

0

0

 

29

Locked

QAM256

657000000 Hz

-4.2 dBmV

37.8 dB

0

0

 

31

Locked

QAM256

669000000 Hz

-4.3 dBmV

37.8 dB

0

0

 

33

Locked

Other

732000000 Hz

-4.7 dBmV

34.8 dB

0

0

 

 

Upstream Bonded Channels

Channel

Channel ID

Lock Status

US Channel Type

Frequency

Width

Power

1

2

Locked

SC-QAM

29600000 Hz

6400000 Hz

55.8 dBmV

2

1

Locked

SC-QAM

36100000 Hz

6400000 Hz

53.8 dBmV

3

3

Locked

SC-QAM

23000000 Hz

6400000 Hz

57.0 dBmV

4

4

Locked

SC-QAM

16500000 Hz

6400000 Hz

59.0 dBmV

 

Current System Time: Tue Aug 7 14:53:41 2018

 

 

Diamond Problem Solver

Re: started unicast maintenance ranging - no response received

The upstream power is too high / out of spec and may be intermittently fluctuating even higher out of spec. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.

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.


Regular Visitor

Re: started unicast maintenance ranging - no response received

What is the correct range for upstream power?

Diamond Problem Solver

Re: started unicast maintenance ranging - no response received

That info is here in the troubleshooting tips;

 

https://forums.xfinity.com/t5/Your-Home-Network/Xfinity-Internet-Connection-Troubleshooting-Tips/m-p...

 

45 dB would be desirable.

Expert

Re: started unicast maintenance ranging - no response received


@DTM2 wrote:

What is the correct range for upstream power?


Downstream Power Levels: -13dBmV to  +13dBmV

Downstream Signal to Noise Ratio (SNR):  >33dB 

Upstream Power Level:  +25dBmV to +54dBmV

Upstream Signal to Noise Ratio (uSNR): >31dB  

Upstream Receive Power: -2dBmV to +2dBmV

See the troubleshooting guide.


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Regular Visitor

Re: started unicast maintenance ranging - no response received

Thanks for the quick replies. I just checked and I don't have any splitters on my setup. I just have internet (no TV). I have a single cable running directly from the outside demark to the modem. I'm going to schedule a Comcast tech to come out and adjust the power.

Expert

Re: started unicast maintenance ranging - no response received

@DTM2

 

I've asked a Comcast employee to help you schedule an appointment. You should expect a reply in this thread. 




I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Regular Visitor

Re: started unicast maintenance ranging - no response received

Thank you

Diamond Problem Solver

Re: started unicast maintenance ranging - no response received


@DTM2 wrote:

I'm going to schedule a Comcast tech to come out and adjust the power.


Good luck with it ! Please post back with how things turn out.

Silver Problem Solver

Re: started unicast maintenance ranging - no response received

I have good upstream numbers in the mid-upper 40's, but I also occasionally get those ranging errors. I can go weeks with no issues, then several times a day.

Official Employee

Re: started unicast maintenance ranging - no response received

 

Hello DTM2, I can get a tech scheduled to repair your signal. To better assist you, please send me a private message with your full name and account number.