> Source: [sk116067](https://support.checkpoint.com/results/sk/sk116067)

# sk116067 - FTP data traffic is blocked with "Violated unidirectional connection"

| Property | Value |
|----------|-------|
| Solution ID | sk116067 |
| Date Created | 2017-02-24 |
| Last Modified | 2019-12-03 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * FTP control traffic on port 21 is allowed
* FTP data traffic on high ports is dropped without any rule number with error message "Violated unidirectional connection"
* According to ruleset, traffic should be allowed by a rule via "any" service

## Cause

FTP services uses "Match for Any" and is used for connections that match a rule via the ANY service:![](https://sc1.checkpoint.com/sc/SolutionsStatics/sk116067/Example_011702262236.jpg)

FTP services does not allow bidirectional data transfer, ftp-bidir should be used.

## Solution

This solution requires authentication. Please log in to view the full solution.

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