> Source: [sk114176](https://support.checkpoint.com/results/sk/sk114176)

# sk114176 - GTP Tunnel traffic is dropped with "Invalid End User IP address" message

| Property | Value |
|----------|-------|
| Solution ID | sk114176 |
| Date Created | 2016-10-27 |
| Last Modified | 2017-06-08 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * SmartView Tracker shows drop of GTP tunnel (port 2151) traffic with reason "Invalid End User IP address", GTP Code: 400  
  ![](https://sc1.checkpoint.com/sc/SolutionsStatics/NEW_SK_NOID1477566041358/11610270417.png)
* Output of kernel debug (`fw ctl zdebug -m gtp + error`) shows dropped traffic:  
  *fwgtp_process_tpdu:Packet EU IP version (6) doesn't match tunnel EU IP version (4);*   
  `
  `**or**   
  `
  `*fwgtp_process_tpdu:Packet EU IP version (4) doesn't match tunnel EU IP version (6);*

## Cause

The reason may be IP version inconsistency with end user IP version that the Security Gateway received during tunnel establishment.

## Solution

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

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