Hi all,
ntpd emits IP/UDP packets with ToS field set to 0xc0.
So that is quite similar to the other issue I (and many others) have with RPI3 when operated over WiFi internal interface.
EDIT:
As workaround, add the following command
Code: Select all
/sbin/iptables -t mangle -I POSTROUTING 1 -o wlan0 -p udp --dport 123 -j TOS --set-tos 0x00
to the file
/etc/rc.local
before the
exit 0 line.
Next reboot and check the sync state of NTP daemon as follows
Code: Select all
ntpq -cpeers
remote refid st t when poll reach delay offset jitter
==============================================================================
-kazan.admin.sar 212.45.144.3 3 u 7 64 3 20.413 1.826 2.975
+vodka.sublink.O 193.204.114.233 2 u 7 64 3 29.012 0.479 1.871
+kraken2.bilink. 193.204.114.232 2 u 7 64 3 29.342 1.270 3.581
*nettuno.ntp.irh 193.204.114.232 2 u 7 64 3 26.978 0.728 3.038
That points to some firmware/driver defect in RPI3 (it seems unable to forward IP packets with ToS != 0).