> Source: [sk183411](https://support.checkpoint.com/results/sk/sk183411)

# sk183411 - "fw_xlate_cliside_server failed" error appears repeatedly in the fwk.elg log file

| Property | Value |
|----------|-------|
| Solution ID | sk183411 |
| Date Created | 2025-05-04 |
| Last Modified | 2025-05-04 |
| Technical Level | Advanced |
| Products | Security Gateway, Scalable Platforms |
| Versions | R82, R81.20, R81.10 (EOS), R82, R81.20, R81.10 (EOS) |

## Symptoms

- This error appears repeatedly in the `fwk.elg` log file even though Network Address Translation (NAT) is not enabled:

`fw_xlate_cliside_server failed`

**Note** : The `fwk.elg` log file is generated by the Firewall Kernel (FWK) process on Security Gateways and Scalable Platforms. It contains detailed debug and error messages related to the operation of the firewall kernel, including information about traffic inspection, policy enforcement, and internal processing.

## Cause

When handling Media Gateway Control Protocol (MGCP) traffic, the `fwconn_record_conn` function calls `fw_mgcp_undo_earlynat`, even if the applicable protocol handler is not in use. It also calls `fw_xlate_cliside_server`, which can return a failure if no NAT was previously applied.
**Notes** :

* The `fwconn_record_conn` kernel parameter controls the recording of connection data within the firewall kernel.
* The `fw_mgcp_undo_earlynat` kernel parameter controls whether the Security Gateway "undoes" (reverses) the Early NAT port translation for MGCP traffic before the packet leaves the Security Gateway.
* The `fw_xlate_cliside_server` kernel parameter is an advanced setting that controls how the Security Gateway handles NAT for server-side connections, particularly in scenarios involving "client-side" and "server-side" NAT.

## Solution

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