Port
Port 389 — LDAP
Port 389 (TCP/UDP) is used by LDAP. Lightweight Directory Access Protocol — directory lookups (e.g. Active Directory).
Port 389 at a glance
| Property | Value |
|---|---|
| Port number | 389 |
| Transport | TCP/UDP |
| Service | LDAP |
| Category | Well-known port |
What it is used for
Lightweight Directory Access Protocol — directory lookups (e.g. Active Directory).
Security considerations
Clear text unless LDAPS (636). Use TLS for binds.
See our full TCP/UDP port reference and learn how firewalls filter ports in the CyberOps course.
Frequently asked questions
What is port 389 used for?
Port 389 (TCP/UDP) is used by LDAP. Lightweight Directory Access Protocol — directory lookups (e.g. Active Directory).
Is port 389 TCP or UDP?
Port 389 uses TCP/UDP.
Is it safe to open port 389?
Clear text unless LDAPS (636). Use TLS for binds.
Related
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