> Source: [sk180838](https://support.checkpoint.com/results/sk/sk180838)

# sk180838 -  Cluster in Load Sharing mode intermittently drops VPN traffic (UDP port 500 or 4500)

| Property | Value |
|----------|-------|
| Solution ID | sk180838 |
| Date Created | 2023-04-20 |
| Last Modified | 2023-04-25 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- * A cluster in Load Sharing Mode intermittently drops VPN traffic (UPD port 500 or 4500) with destination behind the cluster.
* Kernel debug on Security Gateway ('`fw ctl debug -m fw + drop`') shows :

  `f@;16223250;01Nov2022 10:03:51.869851;[vs_0];[tid_1];[fw4_1];fw_log_drop_ex: Packet proto=17 172.25.65.71:65559 -> 192.168.181.183:4500 dropped by fwmultik_process_f2p_cookie_inner Reason: PSL Drop: No connection`

## Cause

VPN code excluded VPN Ports (UDP 500/4500) from connection stickiness. This causes the cluster members to handle the same connection and then drop the traffic.

## Solution

[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 it.  
For faster resolution and verification, collect these files:

1. [CPinfo](https://support.checkpoint.com/results/sk/sk92739) file from the Management Server involved in the case.
2. [CPinfo](https://support.checkpoint.com/results/sk/sk92739) file from the Security Gateway / each Cluster Member involved in the case.

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

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