Configure the NTP service for containers - Elastic Container Instance

Time drift in containers causes subtle but serious problems: distributed systems produce inconsistent data, log timestamps become unreliable for debugging, and requests signed with skewed clocks are rejected. Configure the Network Time Protocol (NTP) service for your Elastic Container Instance (ECI) to keep container clocks accurate.

NTP configuration is only available through the API. You cannot configure it from the console.

Prerequisites

Before you begin, ensure that you have:

An Alibaba Cloud account with permission to call the ECI CreateContainerGroup API operation
The address of at least one NTP server

Configure NTP when creating a container group

Pass one or more NTP server addresses using the NtpServer.N parameter when calling CreateContainerGroup.

Parameter	Type	Example	Description
`NtpServer.N`	Array	`ntp.aliyun.com`	The address of the NTP server. Use `NtpServer.1`, `NtpServer.2`, and so on for multiple servers.

The following example creates a container group named test-ntp with a custom NTP server:

ContainerGroupName=test-ntp
NtpServer.1=100.100.XX.XX
Container.1.Name=nginx
Container.1.Image=registry-vpc.cn-hangzhou.aliyuncs.com/eci_open/centos:7
Container.1.Command=sleep
Container.1.Arg=3600

Verify NTP synchronization

After the container group starts, connect to a container and run:

chronyc sources

If chrony is not installed, you can run the yum -y install chrony command to install chrony.

A successful response lists the configured NTP server:

210 Number of sources = 7
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^* 100.100.XX.XX                 1   4   177    13    +22us[ +153us] +/-   10ms

Confirm NTP is working by checking that your configured server IP address appears in the output and that the MS column shows ^* next to it.