Chrony is an open source free software, it can keep the system clock with the clock server (NTP) synchronization, allowing accurate time-keeping.
It consists of two programs: chronyd and chronyc.
chronyd is a daemon running in the background, the system clock and the clock running in the kernel server is used to adjust the synchronization.
It determines the ratio of increase or decrease in computer time and compensate for this.
For an isolated system, the user may enter the correct time periodically (by chronyc) manually.
In both cases, chronyd determine the ratio of the speed of the computer and correct it.
chronyd realized the NTP protocol and can act as a server or a client.
chronyc chronyd is used to monitor the performance and configuration parameters of the user interface thereof.
He can control the machine and chronyd processes running on other computers.
The main Chrony talk about the installation and configuration of:
【Service-Terminal】
•installation
yum install -y chrony
• edit the configuration file
vim /etc/chrony.conf
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
server 1.centos.pool.ntp.org iburst
server 2.centos.pool.ntp.org iburst
server 3.centos.pool.ntp.org iburst
Replace NTP_SERVER use NTP server name or IP address. Supports a plurality of server configuration values, using the above four default.
allow 192.168.128.0/24
Allow client access
• Restart Service
systemctl enable chronyd
systemctl start chronyd
• Check Time Synchronization
chronyc sources
[Client]
•installation
yum install -y chrony
• edit the configuration file
vim /etc/chrony.conf
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
# server 0.centos.pool.ntp.org iburst
# server 1.centos.pool.ntp.org iburst
# server 2.centos.pool.ntp.org iburst
# server 3.centos.pool.ntp.org iburst
server controller2.service iburst
Comment out this four NTP_SERVER, using our own server-side IP as NTP_SERVER.
• Restart Service
systemctl enable chronyd
systemctl start chronyd
• Check Time Synchronization
chronyc sources
