> Source: [sk150314](https://support.checkpoint.com/results/sk/sk150314)

# sk150314 - RADIUS authentication fails when connecting to Cisco ACS

| Property | Value |
|----------|-------|
| Solution ID | sk150314 |
| Date Created | 2019-04-15 |
| Last Modified | 2020-05-04 |
| Technical Level | Advanced |
| Products | Security Management Server, Endpoint Security |
| Versions | R82.10, R82, R81.20, Cloud, E89.X, E88.X, R82.10, R82, R81.20 |
| OS | Windows, Gaia |

## Symptoms

- * "Authentication Failed" error appears when fail to access RADIUS server via SmartConsole or SmartDashboard.
* *Tcpdump -nnei any port 1812* shows accepted traffic from RADIUS server when performed on the SMS or MDS.
* Cisco ACS shows allowed authentication in the logs for the request.

## Cause

The shared key is most likely mismatched. In such a case, Cisco ACS will not show failure of the shared key in their logs.

## Solution

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

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