Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: pfSense and cable modems.  (Read 1202 times)

Chrysalis

  • Content Team
  • Addicted Kitizen
  • *
  • Posts: 7426
  • AAISP CF
pfSense and cable modems.
« on: November 24, 2022, 01:26:02 AM »

Anyone remember this thread?

https://forum.kitz.co.uk/index.php/topic,24600.0.html

To summarise an issue with people on virgin media seeing spikes and loss was eventually discovered to be related to allowing the dns resolver (unbound) to restart on DHCP registrations, but also seemed to get triggered by using the resolver directly without forwarding to another resolver, at the time it didnt make a lot of sense.

So I have been recently doing some tinkering, and then I noticed something very odd in the early hours of yesterday the 23 November.

The gateway monitoring was very spiky for the entire period I was doing some experiments, which were mostly changing configurations around and monitoring the effects on usage, including some occasional throughput testing.  During this period of time the latency was shooting up into the mid to high 100s.  I then checked my TBB graph to see if it was the connection and the spikes were all on that graph.

I left things alone for a short time, the behaviour stopped, I checked the cable modem, not a cable engineer, but everything looked good, proper modulation on every channel, no time outs, no post RS errors.  I then changed the monitoring to ping the cable modem itself 192.168.100.1 instead of the ISP gateway.

First observation a base latency of 2.5ms.  Second if I monitored it at same time as manual pings running both would get packet loss, but ok if only one of the ping tasks running so some kind of rate limiting whilst its in bridge mode.  Third when these spikes resumed, they also affected the LAN pings, so pretty much confirmation not a internet issue but a cable modem or pfSense problem.

I rebooted both devices and it settled down, but the issue is not gone, with me not using the net interactively for several hours it all settled down, but then me merely logging into pfSense and adjusting a firewall rule, caused a 250ms spike on dpinger to 192.168.100.1 as well as  all other configured internet gateways.  There has also been a second spike as I rechecked just now of which I was merely web browsing, very interesting, I probably have tinkered with too much stuff and caused some breakage somewhere.  But I thought worth posting as that older thread left questions unanswered.
Logged

Chrysalis

  • Content Team
  • Addicted Kitizen
  • *
  • Posts: 7426
  • AAISP CF
Re: pfSense and cable modems.
« Reply #1 on: November 24, 2022, 02:48:45 AM »

Culprit, I had disabled this patch yesterday, enabled again now.

https://redmine.pfsense.org/issues/12827
Logged