ntpd — Common Ports
Community software entries: links are references, not individual verification.
Default Ports (1)
NTP (Network Time Protocol) syncs clocks between clients and servers over UDP 123. A wrong system clock breaks TLS certificate validation, scrambles log ordering and invalidates distributed locks.
NTP
Scope
Port associations on this page are community-database references (common usage), not a live measurement of any machine; confirm with the official documentation before deployment.
Frequently asked questions
What port does ntpd use?
ntpd commonly uses these ports: 123. The default port is 123. These are community database references — actual configuration may differ.
How do I check if ntpd is running?
Run sudo ss -tupn 'sport = :123' on the server to check for listening processes on these ports. Also use systemctl status <service> to check the service state. Without root you may not see other users' processes. A listening port alone does not prove the software identity — verify with the config file and process name.
What category does ntpd belong to?
ntpd belongs to the Time Services category. This page lists the software's port associations and their roles.
Quick Info
- Categories
- Time Services
- Associated ports
- 1
- Aliases
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