> Source: [sk176107](https://support.checkpoint.com/results/sk/sk176107)

# sk176107 - IPSec tunnel sporadically drops traffic in Spark Firewall 1500

| Property | Value |
|----------|-------|
| Solution ID | sk176107 |
| Date Created | 2021-11-13 |
| Last Modified | 2022-07-12 |
| Technical Level | Advanced |
| Products | Spark Firewall (Locally Managed) |
| Versions | R82.00.X, R81.10.X |
| Platform | 1570R, 1500 |

## Symptoms

- IPSec tunnel sporadically drops traffic in Quantum Spark 1500 Appliances.

## Cause

**In 1500 appliances:**

When the IPSec tunnel is not encapsulated (i.e. uses ESP traffic and not NAT-T) there may be sporadic drops on the receiving side.

For example, when running constant ping over the VPN tunnel, 2% of the traffic will be lost. When capturing ESP traffic on the receiving end, those ESP packets are not seen.

## Solution

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

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