> Source: [sk147492](https://support.checkpoint.com/results/sk/sk147492)

# sk147492 - Security Gateway drops ICMP traffic due to: "fw_conn_post_inspect Reason: First server side outbound packet is an ICMP"

| Property | Value |
|----------|-------|
| Solution ID | sk147492 |
| Date Created | 2019-02-19 |
| Last Modified | 2020-01-30 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- Security Gateway drops ICMP traffic due to: "fw_conn_post_inspect Reason: First server side outbound packet is an ICMP"

## Cause

When a connection is accelerated through the Security Gateway, the connection is not properly defined as a VPN connection.

This causes the ICMP request, sent from the source, to be dropped due to "fw_conn_post_inspect Reason: First server side outbound packet is an ICMP"

**\* Note:** This symptom may occur even when VPN is **not** used. This SK applies for such scenarios as well.

## Solution

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

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