> Source: [sk90060](https://support.checkpoint.com/results/sk/sk90060)

# sk90060 - GRE tunnel stops working inside a Site-to-Site VPN tunnel established with Check Point cluster

| Property | Value |
|----------|-------|
| Solution ID | sk90060 |
| Date Created | 2012-12-27 |
| Last Modified | 2022-04-17 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- * GRE tunnel suddenly stops working inside a Site-to-Site VPN tunnel:

  * between Check Point cluster and another Check Point Security Gateway / cluster
  * between Check Point cluster and 3rd party vendor

  Topology:  

  \[Check Point cluster\] --- (VPN) --- \[VPN peer\]
* Kernel debug ('`fw ctl debug -m fw + drop`') on Check Point cluster shows:  

  `;fw_log_drop: Packet proto=47 X.X.X.X:0 -> Y.Y.Y.Y:`*port*` dropped by chain_ipsec_methods_ok Reason: vpn_decrypt_methods_ok failed;`

* Failover between Check Point cluster members does not help.

## Cause

Possible synchronization issue between the Check Point cluster members.

## Solution

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

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