> Source: [sk117694](https://support.checkpoint.com/results/sk/sk117694)

# sk117694 - Link between Check Point Appliance and Switch is down after interface flap

| Property | Value |
|----------|-------|
| Solution ID | sk117694 |
| Date Created | 2017-05-30 |
| Last Modified | 2017-07-18 |
| Technical Level | Advanced |
| Products | Security Gateway, Spark Firewall (Locally Managed), Hardware, Scalable Platforms |
| Versions | R82.10, R82, R81.20, R82.00.X, R81.10.X, Not Version-Specific, R82, R81.20 |
| Platform | 15000, 3000, 5000, 41000 (EOL), 44000, 64000 |

## Symptoms

- * After a interface flap or connection restart the link between the Check Point appliance and the switch is down. The 'ethtool' commnad shows:  
  `Speed: Unknown!`  
  `
  Duplex: Unknown!`
* Check Point appliance is connected to a device that does not support Auto-Negotiation.

## Cause

The Check Point appliance interface automatically autonegotiates the speed and duplex of the connection after the connection resets.

## Solution

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

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