# Configuring DAPP maximum IPv4 ICMP length

Use this procedure to set the maximum IPv4 ICMP length used by DAPP.

## Procedure steps

1. From the navigation tree, double-click QoS.

2. From the QoS tree, double-click QoS Agent.

3. Select the Configuration tab.

4. Under the DoS Attack Prevention Package section, enter a value in the range 0 to 1023 in the DappIpv4IcmpMaxLength text box.

5. Click Apply.