2021-07-02
Be very careful of what you measure
I realized the high maximum IPv4 ping times never showed up when I redid the measurement by hand, and IPv4 was the first test in the crontab line. So I guess a lot of scripts ping ping.xs4all.nl every 5 minutes and it's a bit congested at exactly that time. I added a small delay before the start of the measurement and suddenly the strange peaks are gone.