> Source: [sk105390](https://support.checkpoint.com/results/sk/sk105390)

# sk105390 - Dead Peer Detection (DPD) does not work in Aggressive Mode

| Property | Value |
|----------|-------|
| Solution ID | sk105390 |
| Date Created | 2015-03-26 |
| Last Modified | 2019-04-04 |
| Technical Level | Advanced |

## Symptoms

- * Dead Peer Detection (DPD) negotiation fails in Aggressive Mode.

* During 1st / 2nd packets, DPD Vendor ID payload is not sent (although it should be as per RFC 3706).

* Dead Peer Detection (DPD) works correctly in Main Mode.

## Solution

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