> Source: [sk111132](https://support.checkpoint.com/results/sk/sk111132)

# sk111132 - When using AES-128 with SHA256, negotiation succeeds, but VPN tunnel fails

| Property | Value |
|----------|-------|
| Solution ID | sk111132 |
| Date Created | 2016-05-03 |
| Last Modified | 2018-03-04 |
| Technical Level | Advanced |
| OS | Gaia |

## Symptoms

- * When selecting AES-128 with SHA-256 for IPsec VPN, the negotiation succeeds, but VPN tunnel fails. If change to 3DES it works.  

  ![](https://sc1.checkpoint.com/sc/SolutionsStatics/sk111132/Encryption1605090422.png)
* Kernel crash when AES is used with SHA256.
* IKE negotiation fails with Error "No proposal choosen"

## Cause

Due to sanity check being done on AES encryption algorithm, VPN traffic fails, and an SPI delete packet is sent.

## Solution

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

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