> Source: [sk44576](https://support.checkpoint.com/results/sk/sk44576)

# sk44576 - VPN tunnel between Security Gateways fails for no apparent reason, and kernel debug shows '...dropped by vpn_encrypt_chain Reason: no reason'

| Property | Value |
|----------|-------|
| Solution ID | sk44576 |
| Date Created | 2010-04-12 |
| Last Modified | 2023-02-05 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * VPN tunnel between Security Gateways fails for no apparent reason.  

* IKE debug (per [sk180488](http://supportcontent.checkpoint.com/solutions?id=sk180488)) shows a failure on Phase 1 (Main Mode) - Packet 1 is sent to the VPN peer, and VPN peer sends a reply packet. IKE negotiation does not proceed.  

* Kernel debug ('`fw ctl debug -m fw + drop`') shows that the reply packet from VPN peer is '`...dropped by vpn_encrypt_chain Reason: no reason`'.  

* Configuration in SmartDashboard has been verified for IKE Phase 1 and IKE Phase 2.  

* Either Traditional VPN, or Simplified VPN mode is used.   

* Issue occurs in cluster environment.

## Cause

The VPND daemon fails to pass the packet to ClusterXL layer.

## Solution

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

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