Uncertain Time

Questioning authority of time.
Uncertain time is a basic NTP Server messing with time.

Requirements

A public IP and port 123 pre-routed to port 1234 for accepting and responding to NTP datagrams is required.

For ufw in /etc/ufw/before.rules that looks like

:PREROUTING ACCEPT [0:0]
-A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 8080
-A PREROUTING -p udp --dport 123 -j REDIRECT --to-port 1234
COMMIT

Time on Mac OS

What time is it?

Misc information and discussion
1 2 3

query the time server

ntpq -p  
sntp -d uncertaintime.com

setting the timeserver
systemsetup -setnetworktimeserver uncertaintime.com

set local time to NTP
sudo ntpdate -u uncertaintime.com

NTP servers status
ntpq -p

drift file
cat /var/db/ntp.drift

current time server config
cat /private/etc/ntp.conf

Cool terms

stratum

false ticker

pacemaker

skew