Posted On: Nov 29, 2017

The Amazon Time Sync Service provides a highly accurate and reliable time reference that is natively accessible from Amazon EC2 instances.

Built on Amazon's proven network infrastructure, the service utilizes a fleet of redundant satellite-connected and atomic reference clocks in AWS regions to deliver current time readings of the Coordinated Universal Time (UTC) global standard. The service is designed to be highly available with a continuously monitored time infrastructure and provides a low variance reference time source. Leap seconds are known to cause application errors, and can be a concern for developers and system administrators. The Amazon Time Sync Service automatically smooths out (smears) leap seconds that are periodically added to UTC, so that customers do not have to worry about application errors due to their addition. In the future, we will also provide mechanisms for accessing non-leap smeared time. EC2 instances running in Amazon Virtual Private Cloud (VPC) can access this service at a universally reachable IP address.

The Amazon Time Sync Service is available starting today in all AWS public regions. There is no additional charge for using this service. Customers can use standard Network Time Protocol (NTP) clients in their instances to access the service without needing any updates to their VPC configurations. Instructions to configure NTP clients to access the service are available for Linux and Windows.