Synchronising the clock using NTP in Sabayon Linux

In my previous post I explained how to install Sabayon Linux via the command line from the Sabayon Linux ‘SpinBase’ ISO.

If the system clock in your current installation is not being synchronised with an external time server over the Internet, the simplest way to achieve this is to install the net-misc/ntp package and configure systemd as shown below.

Note that I use net-misc/ntp rather than net-misc/chrony because the latter does not work in my Sabayon Linux installation; after I have configured the Chrony daemon, the command ‘systemctl status chronyd‘ returns the error message ‘Can’t initialise from real time clock, driver not loaded’. Of course, if Chrony happens to be installed and is working fine, you don’t need to do anything at all. But if Chrony is not working correctly and you want to try the ntp daemon instead, before performing the steps below you’ll first need to disable Chrony as explained under ‘Caveat’ at the end of this post.

1. Install the ntp package:
   

   # equo install ntp

2. Enable the ntp daemon so that it starts at boot:
   

   # systemctl enable ntpd
# timedatectl set-ntp true

3. Start the ntp daemon running now:
   

   # systemctl start ntpd

4. Check whether the daemon is running:
   

   # systemctl status ntpd

Below I show the console output for the complete sequence from Step 2 to Step 4 with the command ‘timedatectl status‘ between each step so that you can see the effect. Note that I had previously set the hardware clock time (which, by default, systemd assumes to be UTC) to be the same time as local time. Since BST and UTC do not coincide, clearly both clocks should not both contain 10:06, so watch what happens below once the NTP daemon is launched.

sabayon fitzcarraldo # timedatectl status
      Local time: Mon 2014-09-22 10:06:06 BST
  Universal time: Mon 2014-09-22 09:06:06 UTC
        RTC time: Mon 2014-09-22 10:06:07
        Timezone: Europe/London (BST, +0100)
     NTP enabled: no
NTP synchronized: no
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  Sun 2014-03-30 00:59:59 GMT
                  Sun 2014-03-30 02:00:00 BST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  Sun 2014-10-26 01:59:59 BST
                  Sun 2014-10-26 01:00:00 GMT
sabayon fitzcarraldo # systemctl enable ntpd
ln -s '/usr/lib/systemd/system/ntpd.service' '/etc/systemd/system/multi-user.target.wants/ntpd.service'
sabayon fitzcarraldo # timedatectl status
      Local time: Mon 2014-09-22 10:06:39 BST
  Universal time: Mon 2014-09-22 09:06:39 UTC
        RTC time: Mon 2014-09-22 10:06:39
        Timezone: Europe/London (BST, +0100)
     NTP enabled: no
NTP synchronized: no
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  Sun 2014-03-30 00:59:59 GMT
                  Sun 2014-03-30 02:00:00 BST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  Sun 2014-10-26 01:59:59 BST
                  Sun 2014-10-26 01:00:00 GMT
sabayon fitzcarraldo # timedatectl set-ntp true
sabayon fitzcarraldo # timedatectl status
      Local time: Mon 2014-09-22 10:06:57 BST
  Universal time: Mon 2014-09-22 09:06:57 UTC
        RTC time: Mon 2014-09-22 10:06:58
        Timezone: Europe/London (BST, +0100)
     NTP enabled: yes
NTP synchronized: no
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  Sun 2014-03-30 00:59:59 GMT
                  Sun 2014-03-30 02:00:00 BST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  Sun 2014-10-26 01:59:59 BST
                  Sun 2014-10-26 01:00:00 GMT
sabayon fitzcarraldo # systemctl start ntpd
sabayon fitzcarraldo # timedatectl status
      Local time: Mon 2014-09-22 10:07:13 BST
  Universal time: Mon 2014-09-22 09:07:13 UTC
        RTC time: Mon 2014-09-22 09:07:13
        Timezone: Europe/London (BST, +0100)
     NTP enabled: yes
NTP synchronized: yes
 RTC in local TZ: no
      DST active: yes
 Last DST change: DST began at
                  Sun 2014-03-30 00:59:59 GMT
                  Sun 2014-03-30 02:00:00 BST
 Next DST change: DST ends (the clock jumps one hour backwards) at
                  Sun 2014-10-26 01:59:59 BST
                  Sun 2014-10-26 01:00:00 GMT
sabayon fitzcarraldo # systemctl status ntpd
ntpd.service - Network Time Service
   Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled)
   Active: active (running) since Mon 2014-09-22 10:07:11 BST; 23s ago
 Main PID: 2420 (ntpd)
   CGroup: /system.slice/ntpd.service
           └─2420 /usr/sbin/ntpd -g -n

Sep 22 10:07:11 sabayon ntpd[2420]: Listen normally on 5 eth0 fe80::a00:27ff:fe86:21f3 UDP 123
Sep 22 10:07:11 sabayon ntpd[2420]: peers refreshed
Sep 22 10:07:11 sabayon ntpd[2420]: Listening on routing socket on fd #22 for interface updates
Sep 22 10:07:13 sabayon ntpd[2420]: Deferring DNS for 0.gentoo.pool.ntp.org 1
Sep 22 10:07:14 sabayon ntpd[2420]: Deferring DNS for 1.gentoo.pool.ntp.org 1
Sep 22 10:07:15 sabayon ntpd[2420]: Deferring DNS for 2.gentoo.pool.ntp.org 1
Sep 22 10:07:16 sabayon ntpd[2420]: Deferring DNS for 3.gentoo.pool.ntp.org 1
Sep 22 10:07:18 sabayon ntpd_intres[2422]: DNS 0.gentoo.pool.ntp.org -> 85.236.36.4
Sep 22 10:07:18 sabayon ntpd_intres[2422]: DNS 1.gentoo.pool.ntp.org -> 78.46.197.35
Sep 22 10:07:18 sabayon ntpd_intres[2422]: DNS 2.gentoo.pool.ntp.org -> 91.234.160.19
sabayon fitzcarraldo #

Notice that the NTP daemon synchronised the RTC (hardware clock) time to UTC (I had previously set the hardware clock time to be the same as local time to show what would happen when the NTP deamon was launched). That is correct: notice ‘RTC in local TZ: no‘ in the output above, meaning that systemd by default assumes the time in the RTC is UTC.

By the way, in case you’re wondering, the NTP daemon of course synchronises the time in the system clock too. You do not need to worry: the system clock uses the local time of the time zone you previously configured (see my previous post), so the Linux date command and the clock of the Desktop Environment will show you local time by default.

Caveat
Note that I am using the ntp daemon instead of the Chrony daemon or the OpenNTPD daemon. If Chrony happens to be installed and active in your Sabayon Linux installation, before performing any of the above steps you’ll first need to do the following:

1. Uninstall the Chrony package:
   

   # equo remove chrony

2. Disable the Chrony daemon so that it does not start at boot:
   

   # systemctl disable chronyd
# timedatectl set-ntp false

3. Stop the Chrony daemon running now:
   

   # systemctl stop chronyd

4. Check whether the daemon is still running:
   

   # systemctl status chronyd