Extreme Packet Loss (30+%) multiple hours per day

@flatlander3​ It's just a default x-fi gateway (the tall white rectangles). I don't have any other pieces of equipment. The xFi gateway hooked up to the wall with coax and the ethernet goes directly from the gateway to my computer. I don't have any networking equipment in the loop that isn't provided by comcast. 

@user_9e68ac​ Similar, Black Xfinity gateway, I had a splitter but removed it (had issues before removing splitter as well). I dont know how to provide logs, I am willing to do so if you can explain.

@flatlander3​ Found it, login > troubleshoot > logs

The main event log i have is this 

[Dhcpc][****]: erouter0 T1 Expired, Enter Renew State 

I dont know if the numbers are important so I censored them.

This happens every hour .

Also 

[Dhcpc][*****]: erouter0 got new IP********

occurreda few times  

@Izik​   Ok.  So about every hour for DHCP request.  Every hour is pretty frequent even for ipv6.  When I see that in my market?  They're working on stuff.  I expect some issues.  I preemptively disable ipv6 on my gear (dedicated firewall) because I know their implementation is pretty flaky here and have dealt with it for 2 years.  You don't have the option on Xfinity gear.

The T3 time-outs could be a red hearing, but there are an awful lot of them in a short time and are not helpful.  That's a com error between you and the CTMS.  It can be noise getting injected into the line from someplace.  You are also right.  It might not even be in your building.  In an apartment, you wouldn't have the option to take the gateway outside on a sunny day and trying it where the coax runs into the building so that's out.

So Speculation?  When those DHCP requests are going on, that's UDP.  UDP protocol is a bit lossy.  There is no re-transmit unlike TCP.  If you are hitting timeouts or rebonding channels while that request is happening, you'll break the DHCP conversation.  It will retry at a random interval, but in the mean time, your routing will be broken.  If you look at the gui page that shows you the external IP addresses, the IPV4 or IPV6 may be blank during that time if this is true. Usually, you'd release an address before a rebind/renew, and that's true on most gear.  Normally, it doesn't matter.  You wouldn't notice it in human time.  You can override that on other equipment, and prefer IPV4 over IPV6 for some stability, but you don't have that option either.  It won't fix the problem, but you could make it less frequent.

If you can link the times when you are out, with those DHCP messages happening more frequently than an hour, and a blank IP address, at least you'll know that is a likely candidate for what is going on.  It could just be broken on their end too.   

In any case, I'd pester them again and see if you can get up a tier or two in support.  There are other statistics they can look at from their end and perhaps get someone to take a look at the neighborhood. Some infrastructure dates back to the late 70's and 80's.  

@Izik​ What's your signal table look like?  (power up/downstream/snr/errors etc) .  The original had decent stats.  do you?

In the most ridiculous update I have ever seen, apparently logs now refresh every single day for the xFi routers https://forums.xfinity.com/conversations/your-home-network/modem-gateway-logs-what-do-you-see-is-mine-different/63b313b0507b4d3af9e15222. Ridiculous decision as it makes them useless for troubleshooting persistent issues. I'll throw up the only logs I have from today. I haven't noticed any issues, but googling the forums for the error im seeing seems to indicate it is the potential root cause. I will continue to pull these up whenever i notice extreme problems and upload them here.

Firewall Logs

I also can't seem to find anything in the GUI indicating my external facing IP, I had to go to a third party website that gave me my external facing ipv4 and ipv6 addresses. 

@user_9e68ac​  The firewall won't tell you anything.  It's also pretty light as far as blocked traffic goes.  You should see the logs from known hostile actors, and general background script kid nonsense at some rack space I lease.

Their equipment is worthless for debugging anything, and you don't have any control over anything anyway.  You got the line stats, and that's pretty much it.

If you want to see what's going on for networking, control everything, and be able to debug everything, get a cheap WiFi access point, toss your gateway in bridge mode, and build your own firewall.  I made my own custom distribution out of this one:  https://docs.opnsense.org/  Bridge mode turns your gateway into a pass through device.  The firewall then does the networking. 

@XfinitySara​ Hi, I would like to schedule a tech to come out. I know it is a hardware problem that is out of my control so a tech needs to check all of the external connections that are present as one of them is definitely faulty. The past 2 days, it has been consistent for over 6 hours in the afternoon/evening. I can't play online games at all since I just teleport all over the place and using voice calls is a nightmare because I only hear chunks of what other people are saying. If I run the test in the xfinity app when I'm having these packet loss problems, I am getting results like 2.5mbps, 8mpbs, etc. It is constantly saying I am getting 0% to 5% of my speed. As far as I understand, the test failing in the xfinity app means that it is 100% not a problem internal to my network as that strictly tests the speed to the gateway itself. To reiterate, I would like to schedule a tech to come out and look as I would like to be able to use my internet without the potential for it to become completely unusable.

@user_9e68ac Thanks for following up, we're happy to help troubleshoot and send a tech out if it doesn't work. Please send us a direct chat message with your full name and complete service address to “Xfinity Support”.To do so, click on the chat icon located at the top right of this forums page.

Here's the detailed steps to direct message us:
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