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IPv4 connectivity itermittent issues

New Poster

IPv4 connectivity itermittent issues

Hi,

 

I struggle with this issue for a few months now. IPv4 strarts timing out after 2-10 minutes. IPv6 works fine all the time.

 

To fix IPv4 I disconnect and reconnect to wifi; it works every time.

Another workaround I found is to ping CMTS -t; it works most of the time.

 

I found a thread with a similar issue http://forums.businesshelp.comcast.com/t5/Connectivity/IPv6-working-but-not-IPv4/td-p/25725 where the root cause was duplicated IPv4 address.

I called Comcast and asked for a new IPv4 address. They sent a message to the modem claiming it will get a new IPv4 address but, no, I still have the old one. I think they may just have reset the modem.

 

Can you please help here? What exactly should I ask Comcast on the phone to verify that my IPv4 address is not duplicated or simply get a new IPv4 address? Should a supervisor be able to help?

 

Thanks a lot in advance for help!

 

Some data about my hardware.

Modem: Arris 6190

SNR > 40dB

Power > 6.40 dBmV

I used Arris modem HFC MAC Address for provisioning.

Router: Linksys EA7500 v2 

New Poster

Re: IPv4 connectivity itermittent issues

Thanks in advance for help!

Authorized Vendor

Re: IPv4 connectivity itermittent issues

SB6190 doesnt get an address for CPE your router does..  You can see if your router has a option to change the MAC Address of the WAN interface..  When you do this you will need to reboot your modem or it will not get an address at all..

-------------------------------------
Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
New Poster

Re: IPv4 connectivity itermittent issues

Thanks a lot!

 

Yes, I cloned the MAC and got a different IPv4 address for the router. Unfortunately it did not solve the issue, I still see IPv4 timing out after a few minutes. Smiley Sad

 

I will try next eliminating the router from the equation although it is a brand new replacement - the old one had the same issue. The modem also is brand new.

 

Any other ideas on how to troubleshoot next or what may be the issue?

 

Thanks in advance!

Authorized Vendor

Re: IPv4 connectivity itermittent issues

Try a traceroute the next time..  also can you post your signals and logs..  Make sure to remove your CM-MAC..

-------------------------------------
Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
Contributor

Re: IPv4 connectivity itermittent issues

I have an Arris SB8200 and it loses IPV4 at different times weekly and IPV6 stays connected also.

 

I restart the modem via mobile app and ipv4 comes back online.  SB8200 connected to pFsense appliance latest code.  gigabit tier speed.

 

Standard Specification Compliant DOCSIS 3.1
Hardware Version 4
Software Version D31CM-PEREGRINE-1.0.1.0-GA-04-NOSH

 

Is this the latest code for Comcast/Xfinity?  

 

nothing in event logs since feb,

 

Connection details.

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 519000000 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
5 Locked QAM256 519000000 Hz 4.5 dBmV 41.3 dB 26 107
1 Locked QAM256 495000000 Hz 4.6 dBmV 41.3 dB 31 110
2 Locked QAM256 501000000 Hz 4.7 dBmV 41.3 dB 26 106
3 Locked QAM256 507000000 Hz 4.7 dBmV 41.3 dB 33 103
4 Locked QAM256 513000000 Hz 4.7 dBmV 41.4 dB 26 106
6 Locked QAM256 525000000 Hz 4.3 dBmV 41.3 dB 25 118
7 Locked QAM256 531000000 Hz 3.9 dBmV 40.9 dB 27 112
8 Locked QAM256 537000000 Hz 3.6 dBmV 41.0 dB 24 117
9 Locked QAM256 543000000 Hz 3.2 dBmV 40.9 dB 26 126
10 Locked QAM256 549000000 Hz 2.8 dBmV 40.6 dB 26 121
11 Locked QAM256 555000000 Hz 2.5 dBmV 40.4 dB 21 131
12 Locked QAM256 561000000 Hz 2.3 dBmV 40.4 dB 33 127
13 Locked QAM256 567000000 Hz 2.1 dBmV 40.3 dB 31 124
14 Locked QAM256 573000000 Hz 2.2 dBmV 40.3 dB 38 117
15 Locked QAM256 579000000 Hz 2.2 dBmV 40.5 dB 35 121
16 Locked QAM256 585000000 Hz 2.4 dBmV 40.5 dB 29 119
17 Locked QAM256 591000000 Hz 2.9 dBmV 40.6 dB 28 131
18 Locked QAM256 597000000 Hz 3.4 dBmV 40.6 dB 28 131
19 Locked QAM256 603000000 Hz 3.5 dBmV 40.7 dB 33 128
20 Locked QAM256 609000000 Hz 3.6 dBmV 40.7 dB 31 129
21 Locked QAM256 615000000 Hz 3.5 dBmV 40.7 dB 44 131
22 Locked QAM256 621000000 Hz 3.3 dBmV 40.5 dB 21 145
23 Locked QAM256 627000000 Hz 3.0 dBmV 40.6 dB 31 139
24 Locked QAM256 633000000 Hz 3.0 dBmV 40.5 dB 42 134
159 Locked Other 666000000 Hz 5.2 dBmV 36.5 dB 1652084 1

 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 5 Locked SC-QAM 36500000 Hz 6400000 Hz 39.3 dBmV
2 6 Locked SC-QAM 30100000 Hz 6400000 Hz 39.8 dBmV
3 7 Locked SC-QAM 23700000 Hz 6400000 Hz 40.3 dBmV

 

Current System Time: Sun Mar 4 13:04:02 2018

 

 

Authorized Vendor

Re: IPv4 connectivity itermittent issues


@persesthagreek wrote:

I have an Arris SB8200 and it loses IPV4 at different times weekly and IPV6 stays connected also.

 

I restart the modem via mobile app and ipv4 comes back online.  SB8200 connected to pFsense appliance latest code.  gigabit tier speed.

 


If I took a guess i would say your RF is having issues and when your pFsense is doing the half-life renewal it fails and pFsense then drops v4..  DHCP for v4 is less forgiving then v6..  I would check your connections in the house make sure everything is tight and any splitters in the way are removed if possible..

-------------------------------------
Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
Authorized Vendor

Re: IPv4 connectivity itermittent issues


@persesthagreek wrote:

Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
5 Locked QAM256 519000000 Hz 4.5 dBmV 41.3 dB 26 107
1 Locked QAM256 495000000 Hz 4.6 dBmV 41.3 dB 31 110

 

 

Oh one mroe thing..  If the Uncorrectables are over a couple of days then no big deal it happens to drop packets at times..  But if this was reset within a couple minutes of capturing this data then that could be a problem as well, but once again this points to an RF issue..

-------------------------------------
Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
Contributor

Re: IPv4 connectivity itermittent issues

Ok, thank you for the info.  I replaced the cable and then swapped the splitter with a balanced -5.5 3way and the power level was higher in 8 dBmV and same SNR.

 

I swapped back to a unbalanced -3.5 and (2) -7 and moved the modem up to the -3.5 and higher power levels again.

 

Moved it back to -7 and here are the results.

 

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.

 

Speed is good and before cable and splitter swap haven't had any issues.  fast.com speedtest 640Mbps during the day.

 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 615000000 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
21 Locked QAM256 615000000 Hz 5.1 dBmV 41.1 dB 0 0
1 Locked QAM256 495000000 Hz 5.2 dBmV 41.4 dB 0 0
2 Locked QAM256 501000000 Hz 5.6 dBmV 41.5 dB 0 0
3 Locked QAM256 507000000 Hz 6.1 dBmV 41.6 dB 0 0
4 Locked QAM256 513000000 Hz 6.4 dBmV 41.6 dB 0 0
5 Locked QAM256 519000000 Hz 6.3 dBmV 41.7 dB 0 0
6 Locked QAM256 525000000 Hz 6.0 dBmV 41.7 dB 0 0
7 Locked QAM256 531000000 Hz 5.6 dBmV 41.5 dB 0 0
8 Locked QAM256 537000000 Hz 5.1 dBmV 41.2 dB 0 0
9 Locked QAM256 543000000 Hz 4.6 dBmV 41.1 dB 0 0
10 Locked QAM256 549000000 Hz 4.3 dBmV 40.9 dB 0 0
11 Locked QAM256 555000000 Hz 4.0 dBmV 40.8 dB 0 0
12 Locked QAM256 561000000 Hz 3.7 dBmV 40.7 dB 0 0
13 Locked QAM256 567000000 Hz 3.4 dBmV 40.6 dB 0 0
14 Locked QAM256 573000000 Hz 3.5 dBmV 40.5 dB 0 0
15 Locked QAM256 579000000 Hz 3.5 dBmV 40.8 dB 0 0
16 Locked QAM256 585000000 Hz 3.8 dBmV 40.8 dB 0 0
17 Locked QAM256 591000000 Hz 4.3 dBmV 40.9 dB 0 0
18 Locked QAM256 597000000 Hz 4.7 dBmV 41.1 dB 0 0
19 Locked QAM256 603000000 Hz 5.0 dBmV 41.3 dB 0 0
20 Locked QAM256 609000000 Hz 5.1 dBmV 41.2 dB 0 0
22 Locked QAM256 621000000 Hz 4.8 dBmV 41.0 dB 0 0
23 Locked QAM256 627000000 Hz 4.6 dBmV 40.9 dB 0 0
24 Locked QAM256 633000000 Hz 4.3 dBmV 40.8 dB 0 0
159 Locked Other 666000000 Hz 6.7 dBmV 38.8 dB 86959 0

 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 5 Locked SC-QAM 36500000 Hz 6400000 Hz 38.3 dBmV
2 6 Locked SC-QAM 30100000 Hz 6400000 Hz 39.3 dBmV
3 7 Locked SC-QAM 23700000 Hz 6400000 Hz 39.8 dBmV

 

Current System Time: Wed Mar 14 14:14:05 2018