Specify a Remote NTP Server

Description

Depending on specific functional requirements of a concrete production environment, the Alibaba Cloud Linux 2 system can be configured to utilize the services of the chronyd NTP daemon (the default), or services of the ntpd NTP daemon. Refer to https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/system_administrators_guide/ch-configuring_ntp_using_the_chrony_suite for more detailed comparison of the features of both of the choices, and for further guidance how to choose between the two NTP daemons.
To specify a remote NTP server for time synchronization, perform the following:

• if the system is configured to use the chronyd as the NTP daemon (the default), edit the file /etc/chrony.conf as follows,
• if the system is configured to use the ntpd as the NTP daemon, edit the file /etc/ntp.conf as documented below.

Add or correct the following lines, substituting the IP or hostname of a remote NTP server for ntpserver:

server ntpserver

This instructs the NTP software to contact that remote server to obtain time data.

Rationale

Synchronizing with an NTP server makes it possible to collate system logs from multiple sources or correlate computer events with real time events.