Configure IPv4 Addressing for the Subinterface

Static-Choose this option if you want to assign an address that should not change.

Enter in the interface's IP address and the subnet mask for the network attached to the interface. For example, if you attach the 10.100.10.0/24 network, you could enter 10.100.10.1/24. Ensure that the address you enter is not the network ID or the broadcast address for the network and the address is not already used on the network.

Enter a Standby IP Address and Subnet Mask only if this interface is being used in a high availability pair of devices.

Dynamic (DHCP)-Choose this option if the address should be obtained from the DHCP server on the network. Change the following options if necessary:

• Obtain Default Route-Whether to get the default route from the DHCP server. You would normally check this option.

• DHCP Route Metric-If you obtain the default route from the DHCP server, enter the administrative distance to the learned route, between 1 and 255.

  See Configuring DHCP Server.

  If there is a DHCP server configured for the interface, you are shown the configuration. You can edit or delete the DHCP address pool. If you change the interface IP address to a different subnet, you must either delete the DHCP server, or configure an address pool on the new subnet, before you can save the interface changes.

Continue to " Configure IPv6 Addressing for the Physical Interface" if you want to assign an IPv6 address to this interface as well as an IPv4 address.

Configure Advanced Firepower Interface Options. The advanced settings have defaults that are appropriate for most networks. Edit them only if you are resolving network issues.

If you created the subinterface, go to Enable the Physical Interface.