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TCP and UDP Ports

This user guide applies for both Nodinite LDAP products: BizTalk LDAP Adapter and LDAP Web API and describes the common ports used for LDAP communication

Working with LDAP most probably involves multiple clients and servers. These can run on different operating systems and be scattered on different networks (that can be segmented in various ways). Below is a list of ports that are common for LDAP.

Port Number Port Name Description Comment
53 DNS
88 Kerberos
135 RPC Also used for DTC
139 NetBios-SSN
389 Active Directory, OpenLDAP, Fedora, Sun, NIS, ... Default port
443 HTTPS Should be used for the LDAP Web API
445 SMB (V2, V3) Optional usage with SeriLog file appender
445 msft-ds IPsec ISAKMP
500 or 4500 IPsec ISAKMP ISAKMP uses UDP as its transport protocol. ISAKMP traffic normally goes over UDP port 500 IF NAT-T is used UDP port 4500 is used
1389 OpenDS
3268, 3269 Global Catalog DCs
3269 Global Category List
RPC randomly allocated high TCP ports
10389 Apache Directory Server

Ports marked with the icon are very common and can be considered required and must be allowed in your firewall(s)

You can view the dynamic port range using the following netsh commands: from KB article 832017

  • netsh int ipv4 show dynamicport tcp
  • netsh int ipv4 show dynamicport udp
  • netsh int ipv6 show dynamicport tcp
  • netsh int ipv6 show dynamicport udp