The following table lists the ports that needs to be open for cross forest client management.
| Local Domain | Direction | Remote Domain | TCP | UDP |
| Primary Site server | <-> | Domain Controller | 135 | 123 |
| 139 | 137 | |||
| 3268 | 138 | |||
| 3269 | 389 | |||
| 389 | 464 | |||
| 445 | 53 | |||
| 464 | 88 | |||
| 53 | ||||
| 88 | ||||
| 49152-65535 | ||||
| Primary Site server Database Server | <- | Management Point | 1433 | 1433 |
| 1434 | 1434 | |||
| Primary Site Server | <-> | Distribution Point | 135 | |
| 445 | ||||
| 49152-65535 | ||||
| Upstream Server | <- | Software Update Point | 8530 or 80 | |
| 8531 or 443 |