Visitor
•
5 Messages
Periodic packet loss every 13 seconds
For the last two weeks or so, I've been experiencing packet loss and latency issues. Packet loss only occurs to external destinations, not within my home network, and it happens with routes as short as to my gateway (68.39.72.1).
--- 68.39.72.1 ping statistics ---
124 packets transmitted, 112 received, 9.67742% packet loss, time 24745ms
rtt min/avg/max/mdev = 9.797/16.643/160.792/14.973 ms
Performing a flood ping reveals that every 13 seconds or so, all packets are dropped for 1.1-1.2 seconds. After each loss period, latency is about 10x higher for the first few packets.
...
64 bytes from 68.39.72.1: icmp_seq=549 ttl=254 time=11.0 ms
64 bytes from 68.39.72.1: icmp_seq=550 ttl=254 time=10.7 ms
64 bytes from 68.39.72.1: icmp_seq=551 ttl=254 time=12.5 ms
<- packets dropped
64 bytes from 68.39.72.1: icmp_seq=563 ttl=254 time=219 ms <- high latency
64 bytes from 68.39.72.1: icmp_seq=564 ttl=254 time=116 ms <- high latency
64 bytes from 68.39.72.1: icmp_seq=565 ttl=254 time=14.8 ms <- normal
64 bytes from 68.39.72.1: icmp_seq=566 ttl=254 time=11.3 ms
64 bytes from 68.39.72.1: icmp_seq=567 ttl=254 time=26.0 ms
...
This happens even when my computer is connected directly to the modem and both my computer and the modem have been restarted. The lights on the modem indicate a normal connection. No hardware has changed on my end and I haven't requested any changes in service. I've already spoken with customer service over the phone. They remotely rebooted my modem and confirmed it is working within recommended parameters. My next door neighbor also has Xfinity internet and I confirmed the same loss pattern on their connection. They also said their problems started roughly the same time mine did, so the problem is undoubtedly on Xfinity's end. Please don't ask me to reboot my modem again. Check your own hardware.
kmarzotto
Visitor
•
5 Messages
3 years ago
In the ping output above, the first used a 0.2 second interval and the second used a 0.1 second interval.
0
0
BruceW
Gold Problem Solver
•
26.3K Messages
3 years ago
Network connection problems are often due to poor coax connections or damaged coax cable, usually in or near your home. If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you still need help, please post your Internet plan speed and the following information from your modem or gateway (from http://192.168.100.1 or http://10.0.0.1):
If you can't find the problem or you'd rather have Comcast take care of it, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. It's not likely they can fix the problem remotely. If not, insist they send a tech out to identify the cause and correct it.
If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit ($70-$100) unless you have their Service Protection Plan ( https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device or anything outside your home you shouldn't be charged.
Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post (by scrolling down to "Comment on this post here...") the author of the post you are Commenting on is notified of your response. But if you Reply, the author of the post you are Replying to is NOT notified and may not be aware of your response.
0
0
kmarzotto
Visitor
•
5 Messages
3 years ago
Thank you for the reply. I have the Blast! Internet plan, 300Mbps down, 10Mbps up. The modem is connected with a single coax cable to the wall outlet, no splitters or amplifiers.
Arris Surfboard SB6190
Time
Priority
Description
Fri Apr 01 14:53:32 2022
3
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:53:32 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:53:32 2022
3
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:53:32 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:53:38 2022
5
Lost MDD Timeout;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:53:47 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 14:55:35 2022
3
No Ranging Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:40 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:40 2022
3
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:40 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:41 2022
3
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:41 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:11:46 2022
5
Lost MDD Timeout;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:12:14 2022
5
RCS Partial Service;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Fri Apr 01 15:19:27 2022
3
No Ranging Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Sun Apr 03 13:07:09 2022
4
DHCP RENEW sent - No response for IPv6;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Sun Apr 03 13:07:59 2022
3
No Ranging Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Sun Apr 03 21:21:31 2022
6
TLV-11 - unrecognized OID;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Sun Apr 03 21:21:33 2022
3
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
Sun Apr 03 21:26:54 2022
3
No Ranging Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.0;
0
0
BruceW
Gold Problem Solver
•
26.3K Messages
3 years ago
Downstream power levels are slightly high, but probably not high enough to cause problems. The other signals are all OK, but there are others that the modem does not report, there may be an intermittent problem, and the event log suggests that all is not well.
If Internet Troubleshooting Tips doesn't help you work out the problem your best be is probably to have Comcast send out a premise tech as described previously, especially if nearby neighbors are having the same problem. If the tech can't clear it up they are responsible for passing it up the line to someone who can.
Keep leaning on them until they fix this!
Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post (by scrolling down to "Comment on this post here...") the author of the post you are Commenting on is notified of your response. But if you Reply, the author of the post you are Replying to is NOT notified and may not be aware of your response.
(edited)
0
0
kmarzotto
Visitor
•
5 Messages
3 years ago
After several full outages from Friday through Tuesday -- which I assume were caused by maintenance -- the dropped packet problem went away without further action on my part. Thanks for the assistance!
0
0