> Source: [sk172164](https://support.checkpoint.com/results/sk/sk172164)

# sk172164 - Traffic for Bridge (L2 interfaces) is dropped as "First packet isn't SYN"

| Property | Value |
|----------|-------|
| Solution ID | sk172164 |
| Date Created | 2021-02-21 |
| Last Modified | 2024-06-10 |
| Technical Level | Advanced |
| Products | Scalable Platforms |
| Versions | R81.20, R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- Traffic for Bridge (L2 interfaces) is dropped as "`First packet isn't SYN.`

<br />

## Cause

If the user configures bridge interfaces with the same distribution mode in Smart Dashboard (internal / internal or external / external), the request and reply may be distributed to different SGMs, with NO CORRECTION APPLIED.  

As a result, traffic is dropped as "`First packet isn't SYN`".

<br />

## Solution

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

---

# Agent Instructions

This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.

## Navigating This Knowledge Base

- **Complete index**: [llms.txt](https://support.checkpoint.com/llms.txt)
- **All SK articles**: [SecureKnowledge Sitemap](https://support.checkpoint.com/sitemaps/secureknowledge-sitemap-index.xml)
- **SK article URL pattern**: `https://support.checkpoint.com/results/sk/{skId}`
- **Markdown responses**: AI bot User-Agents automatically receive `text/markdown` content