Setup guides should include setup for systemd/timesyncd

[Michael Rothwell]

https://developers.google.com/time/guides

e.g.,

1) make  /etc/systemd/timesyncd.conf look like:

[Time]

NTP=time1.google.com time2.google.com time3.google.com time4.google.com

2) enable ntp

# timedatectl set-ntp true

3) restart timesyncd

# systemctl restart systemd-timesyncd.service

4) check the status ("Synchronized to time server..." should say time1.google.com or similar)

# systemctl status systemd-timesyncd.service

● systemd-timesyncd.service - Network Time Synchronization

   Loaded: loaded (/lib/systemd/system/systemd-timesyncd.service; enabled; vendor preset: enabled)

  Drop-In: /lib/systemd/system/systemd-timesyncd.service.d

           └─disable-with-time-daemon.conf

   Active: active (running) since Mon 2018-03-26 01:20:53 UTC; 5min ago

     Docs: man:systemd-timesyncd.service(8)

 Main PID: 4212 (systemd-timesyn)

   Status: "Synchronized to time server 216.239.35.0:123 (time1.google.com)."

    Tasks: 2

   Memory: 268.0K

      CPU: 8ms

   CGroup: /system.slice/systemd-timesyncd.service

           └─4212 /lib/systemd/systemd-timesyncd

Mar 26 01:20:53 b systemd[1]: Starting Network Time Synchronization...

Mar 26 01:20:53 b systemd[1]: Started Network Time Synchronization.

Mar 26 01:20:53 b systemd-timesyncd[4212]: Synchronized to time server 216.239.35.0:123 (time1.google.com).

5) timedatectl should report network time on/synced

# timedatectl status

      Local time: Mon 2018-03-26 01:26:41 UTC

  Universal time: Mon 2018-03-26 01:26:41 UTC

        RTC time: Mon 2018-03-26 01:26:41

       Time zone: Etc/UTC (UTC, +0000)

 Network time on: yes

NTP synchronized: yes

 RTC in local TZ: no