This guide shows how to fix ADP issue when alert Flooding UDP on Port 4500.
Symptoms may include
- IPSec packet loss
- Firewall detects packets from VPN tunnel as flood and drops packets.
- other symptoms and messages in logs
- Disabling the tunnel or rebooting the device does not change the behavior.
Solution:
Create a whitelist entry for Port 4500 to fix it. (See picture)
Go to:
Configuration -> Security Policy -> ADP -> Allow List -> Click "Add" and configure as below.