= NTP Synchronization =

== Nodus ==

* Nodus runs an NTP server using chronyd. The configuration files are present at: {{{/etc/chronyd.conf}}}

* Nodus uses 4 servers from rhel.pool.ntp.org as ntp servers.

== FB1 and FE subnetwork ==
This was successfully implemented by Jamie. See elog [[https://nodus.ligo.caltech.edu:8081/40m/16302 | 40m/16302]] for complete details.

=== Server ===

* fb1 runs the ntp server used by FE computers. This is run through ntp with configuration file present in {{{/etc/ntp.conf}}}

* fb1 uses 4 servers from debian.pool.ntp.org as ntp servers.

* ntp is configured to serve the front end network by using: broadcast 192.168.123.255

=== Clients ===

* All FE computers use fb1 at the ntpservers.

* The configuration files for FE ntp service is present in on fb1 {{{/diskless/root/etc/systemd/timesyncd.conf}}}

* To change anything in FE computers, one needs to chroot into the root chroot jail which is exported to the FEs as their os.

   {{{
   sudo chroot /diskless/root.jessie /bin/bash
   }}}

* This will take you to the terminal in debian os which is exported to FEs. You can use apt-get to install anything here.

* Logging into FEs themselves, one can not edit or add any file as the whole filesystem is read-only and imported from fb1. But one can check the status of timesyncd service and  ntp synchronization status by:
{{{
sudo systemctl status systemd-timesyncd
}}}
{{{
timedatectl
}}}