Managing System Time and NTP on Linux

Check Current Time

timedatectl
date

Set Timezone

# List available timezones
timedatectl list-timezones | grep America

# Set timezone
sudo timedatectl set-timezone America/New_York

NTP Synchronization

Accurate time is critical for SSL certificates, logging, cron jobs, and distributed systems.

# Check NTP status
timedatectl show-timesync --all

# Enable NTP
sudo timedatectl set-ntp true

Using chrony (Recommended)

sudo apt install -y chrony
sudo systemctl enable --now chronyd

# Check sync status
chronyc tracking
chronyc sources -v

Manual Time Servers

Edit /etc/chrony/chrony.conf:

server time.cloudflare.com iburst
server time.google.com iburst
server pool.ntp.org iburst

sudo systemctl restart chronyd

Why Time Matters

• SSL/TLS — certificates validated against system time
• Logging — accurate timestamps for debugging and compliance
• Cron jobs — scheduled tasks depend on correct time
• 2FA/TOTP — time-based tokens require synchronized clocks