Ubuntu 20.04 time sync problems and possibly incorrect status information

 admin@ubuntu:~$ sudo timedatectl

[sudo] password for admin: 
               Local time: Fri 2020-07-10 09:14:14 EDT  
           Universal time: Fri 2020-07-10 13:14:14 UTC  
                 RTC time: Fri 2020-07-10 13:14:14      
                Time zone: America/New_York (EDT, -0400)
System clock synchronized: no                           
              NTP service: n/a                          
          RTC in local TZ: no                           
admin@ubuntu:~$ 

The timedatectl command reports that NTP is in use when either chronyd or systemd-timesyncd is enabled and running. 

timesyncd and ntpd are both time synchronization services available in Linux, but they differ significantly in terms of functionality, complexity, and use cases. Here's a breakdown of the key differences and insights on which might be better depending on your needs.
1. Purpose and Use Cases
- systemd-timesyncd:
Purpose: A simple NTP client built into systemd for basic time synchronization with remote NTP servers.
Use Case: Suitable for desktop users, lightweight servers, or environments where you need reliable, accurate time synchronization without the need for advanced features like custom time configurations.
- ntpd (Network Time Protocol Daemon):
Purpose: A full-featured, standalone NTP implementation that provides both time synchronization and advanced configuration options.
Use Case: Ideal for environments where high precision, custom configurations, or time server capabilities are required, such as in data centers, enterprise systems, or networks with complex timekeeping needs.
2. Functionality and Features
- systemd-timesyncd:
Simple NTP client.
Uses fewer system resources and has low overhead.
Primarily synchronizes time with external NTP servers, without providing time to other systems.
Does not support advanced NTP features like hardware timestamping, precise timekeeping, or local clock stratum levels.
- ntpd:
A full NTP implementation, supporting both client and server modes.
Can serve as an NTP server, distributing time to other systems.
Supports complex configurations (e.g., peering between NTP servers, multiple time sources, clock discipline, leap second handling).
Provides higher precision, including microsecond-level accuracy, depending on the hardware and network conditions.
Can be configured to use hardware reference clocks (e.g., GPS receivers) for high-precision timekeeping.
3. Ease of Use and Configuration
- systemd-timesyncd:
Easy to use and configure, with minimal setup required.
Configuration is done through a basic /etc/systemd/timesyncd.conf file or automatically via DHCP.
Suitable for users who just need accurate time synchronization without delving into detailed configurations.
- ntpd:
More complex to set up and configure due to its extensive feature set.
Requires manual configuration of NTP servers in /etc/ntp.conf.
Offers more detailed control over time synchronization, but may require deeper knowledge of NTP protocols and time synchronization principles.
4. Resource Usage
- systemd-timesyncd:
Lightweight, with very low CPU and memory overhead.
Designed for systems where minimal resource consumption is critical (e.g., embedded devices, lightweight servers).
- ntpd:
Consumes more resources, though still fairly low for most modern systems.
May be overkill for systems that only need basic time synchronization, given its complexity.
5. Precision
- systemd-timesyncd:
Provides good enough precision for most non-critical use cases (within milliseconds or tens of milliseconds).
- ntpd:
Offers higher precision (down to microseconds, depending on the hardware and network).
Better suited for applications where precise timekeeping is essential, such as financial systems, scientific experiments, or real-time systems.
6. Which Is Better?
- systemd-timesyncd is better if:
You need simple, reliable time synchronization without any advanced requirements.
You're running a lightweight server, desktop, or embedded device where resource efficiency is important.
You prefer simplicity and minimal configuration.
Precision requirements are not extremely high (milliseconds are acceptable).
- ntpd is better if:
You require high-precision time synchronization (microsecond accuracy or better).
You need to configure a time server to serve time to other devices on the network.
You need advanced NTP features, such as hardware clock synchronization, multiple time sources, or peer mode.
You are working in an environment with strict timekeeping requirements, such as in scientific research, finance, or real time systems.
7. Alternatives:
chrony: Another time synchronization tool that is often considered a middle ground between timesyncd and ntpd. It is lightweight like timesyncd but offers many advanced features and higher precision, making it a popular choice for server environments.
Summary:
timesyncd: Ideal for most typical users and servers where simplicity and lightweight functionality are key.
ntpd: Ideal for complex environments where precise timekeeping, server configurations, and advanced NTP features are necessary.
chrony: A strong alternative that combines the simplicity of timesyncd with some of the advanced features of ntpd.