Time sync issues between server and clients.

Time synchronization issues between servers and clients can lead to various problems, including incorrect logging, authentication failures, and more. Here's a step-by-step approach to address this problem:

1. Verify NTP Configuration:
   • Ensure that Network Time Protocol (NTP) or a similar time synchronization service is installed and properly configured on both the server and client systems.
2. Check NTP Service Status:
   • Verify that the NTP service is running and operational on both the server and client systems. You can use commands like ntpstat or timedatectl to check the status.
3. Select Reliable NTP Servers:
   • Make sure that your NTP servers are reliable and have a low latency. Consider using reputable public NTP servers or local NTP servers within your network.
4. Configure NTP Servers:
   • Update the NTP configuration files (usually /etc/ntp.conf on Linux systems) to specify the NTP servers you want to sync with.
5. Restart NTP Service:
   • After making changes to the NTP configuration, restart the NTP service to apply the new settings.
6. Check Firewall Rules:
   • Ensure that your firewall allows NTP traffic (UDP port 123) to pass through. If not, adjust the rules to permit NTP communication.
7. Check System Timezones:
   • Confirm that the server and client systems are set to the correct time zones. Use the timedatectl command on Linux systems to view and set the timezone.
8. Check Hardware Clock Settings:
   • Verify that the hardware clock (BIOS/UEFI clock) is set correctly. You can use the hwclock command on Linux systems to interact with the hardware clock.
9. Synchronize Hardware and System Clocks:
   • If the hardware clock and system clock are out of sync, use commands like hwclock --systohc to sync them.
10. Monitor Time Drift:
    • Monitor the time drift between the server and clients over time to ensure that it remains within an acceptable range.
11. Enable NTP Logging:
    • Enable NTP logging to review any potential issues or warnings related to time synchronization.
12. Consider Using Chrony (if applicable):
    • Depending on your system and requirements, consider using Chrony as an alternative to NTP. It offers more accurate timekeeping for systems with sporadic internet connectivity.
13. Avoid Using Local Clock as a Time Source:
    • Avoid using the local clock (127.127.1.0) as a time source in your NTP configuration, as it can lead to synchronization issues.
14. Set Up NTP Client on Windows:
    • For Windows systems, ensure that the Windows Time service (w32time) is configured to sync with reliable NTP servers.
15. Perform Regular Time Checks:
    • Schedule regular checks to monitor the time synchronization status and correct any deviations promptly.

By following these steps, you should be able to address time synchronization issues between your server and clients. Regular monitoring and maintenance of time synchronization are important for maintaining accurate logs and the proper functioning of various services.