If you enable the Windows Firewall or if there is an external Firewall for your Active Directory Domain Services (ADDS) in this case Domain Controller Server, you need to set up the allowed port for Domain Controller corectly. The table below will show you all ports that needed for domain controller.

TCP and UDP 389Directory, Replication, User and Computer
Authentication, Group Policy, Trusts
LDAP
TCP 636Directory, Replication, User and Computer
Authentication, Group Policy, Trusts
LDAP SSL
TCP 3268Directory, Replication, User and Computer
Authentication, Group Policy, Trusts
LDAP GC
TCP 3269Directory, Replication, User and Computer
Authentication, Group Policy, Trusts
LDAP GC SSL
TCP and UDP 88User and Computer Authentication, Forest-Level
Trusts
Kerberos
TCP and UDP 53User and Computer Authentication, Name Resolution,
Trusts
DNS
TCP and UDP 445Replication, User and Computer Authentication, Group
Policy, Trusts
SMB,CIFS,SMB2, DFSN, LSARPC, NbtSS, NetLogonR, SamR,
SrvSvc
TCP 25ReplicationSMTP
TCP 135ReplicationRPC, EPM
TCP DynamicReplication, User and Computer Authentication, Group
Policy, Trusts
RPC, DCOM, EPM, DRSUAPI, NetLogonR, SamR,
FRS
TCP 5722File ReplicationRPC, DFSR (SYSVOL)
UDP 123Windows Time, TrustsWindows Time
TCP and UDP 464Replication, User and Computer Authentication,
Trusts
Kerberos change/set password
UDP DynamicGroup PolicyDCOM, RPC, EPM
UDP 138DFS, Group PolicyDFSN, NetLogon, NetBIOS Datagram
Service
TCP 9389AD DS Web ServicesSOAP
UDP 137User and Computer Authentication,NetLogon, NetBIOS Name Resolution
TCP 139User and Computer Authentication,
Replication
DFSN, NetBIOS Session Service,
NetLogon

If you also deploy the DHCP service in domain controller, you also need to allow the ports that needed for DHCP service.

For more detail about the ports that needed on windows server, you can try the following link https://support.microsoft.com/en-in/help/832017/service-overview-and-network-port-requirements-for-windows