> Source: [sk119302](https://support.checkpoint.com/results/sk/sk119302)

# sk119302 - "First packet isn't SYN" drops logs for TCP traffic received from Cisco Wide Area Application Services (WAAS)

| Property | Value |
|----------|-------|
| Solution ID | sk119302 |
| Date Created | 2017-07-26 |
| Last Modified | 2019-03-20 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- "`First packet isn't SYN`" drops logs for TCP traffic received from [Cisco Wide Area Application Services (WAAS)](http://www.cisco.com/c/en/us/support/routers/wide-area-application-services-waas-software/tsd-products-support-series-home.html).

## Cause

Cisco WAAS may change the TCP sequence in the packets. As a result, Check Point Security Gateway would not be able to match the packets to the recorded connection and will drop them.

## Solution

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

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