time-ubuntu.md

Managing time in ubuntu

Configure Timekeeping

Ubuntu has time synchronization built in and activated by default using systemd’s timesyncd service. Verify it’s running correctly.

$ timedatectl

The NTP service should be active. If not then run:

$ sudo timedatectl set-ntp on

Change time

Since systemd was introducted in Ubuntu, the correct way is:

$ timedatectl set-time "RFC 3339-compliant string"

e.g.

$ timedatectl set-time "2002-10-02T10:00:00-05:00"
$ timedatectl set-time "10:35"
$ timedatectl set-time "+2 hours"

This also works with e.g. sudo date --set="+2 hours", which is exactly what I needed.

Setting time zones

Setting time zones: timedatectl set-timezone Australia/Melbourne 

Getting time from command line

sean@sean-B550-AORUS-PRO-AX:~/oxen-core/src/rpc$ date
Thu 19 May 2022 12:59:44 AEST
sean@sean-B550-AORUS-PRO-AX:~/oxen-core/src/rpc$ date -u
Thu 19 May 2022 02:59:46 UTC
sean@sean-B550-AORUS-PRO-AX:~/oxen-core/src/rpc$ date +%s
1652929188