@GeorgeCZ58 said in Diagnosing latency spikes:
how did you resolve the issue?
Maybe he changed ISP.. nowhere in his testing did he show pfsense had anything to do with this - the only way to show that pfsense adding latency would be to sniff on the in out interfaces..
Here is his test without pfsense..
1. AS??? 10.208.128.1 87.6% 1000 2.2 4.1 1.1 53.3 5.7
To the first hop, but then hops after that show zero.. So that points to the device just not answering.. Now if he showed 87.6 loss or higher on every hop after that - then he could pretty safely say there is an issue with connectivity.
if you show a traceroute and all of sudden somewhere down the line you see loss, and that loss is with every hop after that, then that points to actual loss. But loss to specific hop and then zero or much lower points to the device with high just not answering all of the pings, or not answering them in a timely manner, etc.
Since in his pfsense is not listed as a hop in his first trace, would see he is tracing from pfsense directly - so pfsense isn't even nating or routing the traffic.. But some how it still adds latency to the return of something it sends out?? So what he got the answer but didn't actually process its return for X ms?
There was a recent thread where user thought pfsense was adding latency and showed him how to test..
Here sniffing on wan and lan at same time, from time traffic hit wan and pfsense sent it out lan it added a whole 0.000114 seconds.
https://forum.netgate.com/post/1112354