> Source: [sk180855](https://support.checkpoint.com/results/sk/sk180855)

# sk180855 - Site to Site VPN traffic in Load Sharing cluster is not synchronized across members and dropped

| Property | Value |
|----------|-------|
| Solution ID | sk180855 |
| Date Created | 2023-04-30 |
| Last Modified | 2023-08-14 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R81.20, R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- In a Site to Site VPN, when one of the sites is a cluster in Load Sharing mode, packets are dropped with "*vpn_decrypt_verify Reason: CONN_ENC_NO_ENTRY\[_SR\] with packet reversed to the original direction of the connection*"

## Cause

When one of the sites is a cluster in Load Sharing mode, both peers open renegotiation simultaneously, and each side uses different tunnel for encryption. This can be seen in the *Ike.elg* file: the Security Gateway and the peer send renegotiations at the same time.  
It causes incorrect destination member calculation for asymmetric connection and leads to traffic drops.

## Solution

This problem was fixed. The fix is included in:

* [Jumbo Hotfix Accumulator for R81.20](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.20/Default.htm) starting from Take 26
* [Jumbo Hotfix Accumulator for R81.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.10/Default.htm) starting from Take 95
* [Jumbo Hotfix Accumulator for R81](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81/Default.htm) starting from Take 87

<br />

Install this Take on every member of the VPN that is a cluster.   

**To enable the fix** , enable the kernel parameter on each Security Gateway:  
`[Expert@HostName]# ckp_regedit -a SOFTWARE/CheckPoint/VPN1 ikev1_initiator_opens_reneg -n 1`  
To apply the change, kill the VPND/IKED processes.  

**To disable the fix** , run on each Security Gateway:  
`[Expert@HostName]# ckp_regedit -d SOFTWARE/CheckPoint/VPN1 ikev1_initiator_opens_reneg`  
To apply the change, kill the VPND/IKED processes.  

If you choose not to upgrade, Check Point can supply a **Hotfix** . [Contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for this issue.  
A Support Engineer will make sure the Hotfix is compatible with your environment before providing the Hotfix.  
For faster resolution and verification, please collect [CPinfo files](http://supportcontent.checkpoint.com/solutions?id=sk92739) from the Security Management Server and Security Gateways involved in the case.

**Hotfix installation instructions:**   
Refer to [sk168597 - How to install a Hotfix](https://support.checkpoint.com/results/sk/sk168597).

<br />

<br />

**If the Hotfix cannot be installed** , the kernel parameter can be set to force FnA for encrypted traffic:   
`[Expert@HostName]# fw ctl set int try_prevent_fna_for_vpn 0`  

Note: This can introduce traffic slowness.

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