What could explain packet loss for a specific host until pfSense is rebooted?
I ran into an issue today where my server (running Smokeping) started reporting ~8% packet loss for every single host I was monitoring outside of my network.
pfSense itself was reporting 0% packet loss on the WAN, and when I ran ping tests from a computer on the same VLAN as my server I was seeing 0% packet loss as well.
My first attempt was to reboot the server, but that had no affect. Then I rebooted the modem, and that also had no affect. But after rebooting pfSense the packet loss reported by Smokeping was gone and it's back to 0% packet loss across the board.
I haven't seen anything like this before. Usually if Smokeping is reporting packet loss, I'll also see my WAN on pfSense reporting packet loss as well. But in this specific case it appears that the packet loss was limited to a specific host on my network (or rather, of the 4 hosts I checked from, only 1 was reporting packet loss).
I'm not sure what rebooting pfSense cleared up. I did try to reset all of the states at one point but that also had no affect. This issue did crop up after I was tinkering with two different things:
1.) Enabling two new IPSec tunnels (using split tunnels). But disabling these tunnels had no affect
2.) I have been enabling IPv6 on multiple different VLAN's of mine. After I finish setting everything up, I go to my WAN interface and save the page, then apply changes, which seems to kick everything into working. I've done this about 8 different times this week with no issue, but this specific issue happened close to the time when I started seeing packet loss on this server of mine. Could be a lucky coincidence though.
Has anyone else ever seen anything like this before? If I see this again, what else should I try looking into? I would typically say this is a server issue, switch issue, or cabling issue... but restarting pfSense fixed this... so... I dunno :).