NTP Synchronization
Servers
* 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 runs the central ntp server used by martian. This is run through ntp daemon with configuration file present in /etc/ntp.conf
* fb1 uses nodus and caltech ntp server (131.215.239.14 or ntp-02.caltech.edu)
* All FE computers use fb1 and nodus as the ntpservers and run ntp client using ntp daemon service.
* The configuration files for FE ntp service is present in on fb1 /diskless/root.jessie/etc/ntp.conf
* To change anything in FE computers, one needs to chroot into the root.jessie chroot jail which is exported to the FEs as their os.
chroot /diskless/root.jessie /bin/bash
* This will take you to 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 ntp service by:
sudo systemctl status ntp
and
ntpd -pn