> Source: [sk113236](https://support.checkpoint.com/results/sk/sk113236)

# sk113236 - TCP traffic fails to return from static NAT host when using ISP Redundancy and SecureXL

| Property | Value |
|----------|-------|
| Solution ID | sk113236 |
| Date Created | 2016-09-06 |
| Last Modified | 2020-02-03 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * TCP traffic fails to return from static NAT host when using ISP Redundancy and SecureXL.
* When trying to reach internal host using ICMP, the traffic reaches the host and returns as expected. However, when trying TCP traffic, such as LDAP (389), the traffic reaches the host and leaves it to the gateway and is then lost.

## Solution

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