> Source: [sk184426](https://support.checkpoint.com/results/sk/sk184426)

# sk184426 - StrongSwan Client fails to establish a Remote Access VPN connection with a Centrally Managed Spark  Firewall appliance running R81.10.10

| Property | Value |
|----------|-------|
| Solution ID | sk184426 |
| Date Created | 2025-12-11 |
| Last Modified | 2026-05-03 |
| Technical Level | General |
| Products | Spark Firewall (Locally Managed) |
| Versions | R81.10.X |
| Platform | 1500 |

## Symptoms

- * StrongSwan client cannot establish a Remote Access VPN connection with a centrally managed Spark Firewall Appliance running R81.10.10.

* IKEv2 initial negotiation p(IKE_SA_INIT) completes successfully.

* After the client sends child_SA packets (IKEv2_AUTH), the appliance does not respond.

* VPN debug and packet capture (tcpdump) show "Decryption Failed" errors.

## Cause

IKEv2 child Security Association (child_SA) negotiation fails due to incomplete support for StrongSwan authentication in centrally managed appliances running R81.10.10.

## Solution

This problem was fixed. The fix is included starting from:

* [R81.10.15](https://support.checkpoint.com/results/sk/sk182438)

Check Point recommends to always upgrade to the [Recommended version](https://support.checkpoint.com/results/sk/sk183153).

If you choose not to upgrade, [contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for your version.

A Support Engineer will make sure the Hotfix is compatible with your environment before providing it.

**Hotfix installation instructions:**   
Refer to [sk168597 - How to install a Hotfix](https://support.checkpoint.com/results/sk/sk168597).

**After the upgrade:**

1. Verify that the StrongSwan client can successfully establish a Remote Access VPN connection.

2. Confirm that the VPN tunnel establishes successfully and traffic flows as expected.

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