Important ports and their purposes
Published in
1 min readFeb 9, 2021
Ports:
TCP: 53, 135, 389, 445 ,464, 636, 3268, 3269, 49152–65535
UDP: 53, 88, 135, 389, 445, 464, 636, 3268, 3269, 123, 137, 138
Purpose of the ports:
- UDP Port 88 for Kerberos authentication
- UDP and TCP Port 135 for domain controllers-to-domain controller and client to domain controller operations.
- TCP Port 139 and UDP 138 for File Replication Service between domain controllers.
- TCP and UDP Port 389 for LDAP to handle normal queries from client computers to the domain controllers.
- TCP and UDP Port 445 for File Replication Service
- TCP and UDP Port 464 for Kerberos Password Change
- TCP Port 3268 and 3269 for Global Catalog from client to domain controller.
- TCP and UDP Port 53 for DNS from client to domain controller and domain controller to domain controller.
- UDP Port 123: NTP
- UDP Port 137: NetBIOS Name Resolution
- TCP Port 49152–65535: Random Port for RPC
Reference:
https://docs.microsoft.com/en-us/troubleshoot/windows-server/networking/service-overview-and-network-port-requirements#4