> Source: [sk180971](https://support.checkpoint.com/results/sk/sk180971)

# sk180971 - L2TP / StrongSwan clients disconnect after upgrade to R81.10

| Property | Value |
|----------|-------|
| Solution ID | sk180971 |
| Date Created | 2023-05-17 |
| Last Modified | 2024-07-28 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.10 (EOS) |
| OS | Gaia |

## Symptoms

- * L2TP / StrongSwan clients disconnect after upgrade of a Remote Access VPN Gateway to R81.10.
* L2TP / StrongSwan clients disconnections occur from 2 to 30 minutes after the upgrade.
* The logs show that the user initiated the disconnections ("`User-initiated Logout`"), but no user initiated the disconnection.

## Cause

In newer versions of Linux, these ciphers were removed:  

* 3DES
* AES-128
* SHA-1
* Diffie-Hellman Group 2 (1024)
These ciphers are set as defaults for Remote Access VPN. Therefore, they are the default for L2TP clients.

## Solution

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

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