Port 636
ldaps · TCP/UDP
| Range | System/well-known port (0–1023) |
|---|---|
| Protocol | TCP/UDP |
| Service | ldaps |
Frequently asked questions
What is port 636 used for?
Port 636 is registered with the IANA for ldaps (TCP/UDP). Description: ldap protocol over TLS/SSL (was sldap).
Is port 636 a well-known port?
Yes. Port 636 is in the range 0–1023 (system or well-known ports). On Linux and macOS only privileged processes may bind to these ports.
How do I check whether port 636 is open?
Locally on Linux with ss -tulpn | grep ':636\b', on Windows with netstat -ano | findstr :636. To test a remote host use Test-NetConnection <host> -Port 636 in PowerShell or nc -zv <host> 636 on Linux/macOS.
How do I open port 636 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 636/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=636/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 636" -Direction Inbound -Protocol TCP -LocalPort 636 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | ldaps | ldap protocol over TLS/SSL (was sldap) |
| UDP | ldaps | ldap protocol over TLS/SSL (was sldap) |