> Source: [sk106853](https://support.checkpoint.com/results/sk/sk106853)

# sk106853 - Tunnel Test packets are dropped with "ICMP Port Unreachable" error 

| Property | Value |
|----------|-------|
| Solution ID | sk106853 |
| Date Created | 2015-07-15 |
| Last Modified | 2023-05-22 |
| Technical Level | Advanced |
| Products | Endpoint Security |
| Versions | Cloud, E89.X, E88.X |

## Symptoms

- * The Tunnel Test packets from VPN peers - clients and gateways - are not answered by the gateway, returning "ICMP Port Unreachable".  

* Site to Site VPN tunnel is working properly, but it is reported to be down in SmartView Monitor because the tunnel tests are not getting replies.  

* Remote Access VPN clients disconnect because the tunnel tests are not getting replies.

## Cause

In SmartConsole \> Policy \> Global Properties: "Accept control connections" checkbox is not selected.

VPND listens to port 18234 (Tunnel Test port) on a specific interface, whereas the tunnel tests that arrive might have a destination to another interface - whichever IP the peer uses to send the tunnel tests.

The "Control Connections" also include an "implied NAT rule", which translates the destination of Tunnel Test packets.

## Solution

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

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