Cisco 819-4G like WAN for connect to firewall

[jmaria.capzap]

Dear, 

Dear,
I need help to solve this scenario. I want to connect the Cisco 819-4G router to the WAN interface of a firewall device, it is necessary for the Cisco 4G router to assign the public IP of the mobile operator to the WAN firewall interface.

The firewall by DDNS will assign a name for when this ip public changes; to be able to use this WAN for an ipsec tunnel.

[Georg Pauwen]

Hello,

the only way I can see this happening is by configuring your 819 in transparent bridge mode. The below effectively turns your 819 into a switch. I am not sure if that works in your scenario...

hostname R819
!
no ip routing
!
bridge 1 protocol ieee
!
interface FastEthernet0
no ip address
bridge-group 1
!
interface FastEthernet1
no ip address
bridge-group 1
!
interface FastEthernet2
no ip address
bridge-group 1
!
interface FastEthernet3
no ip address
bridge-group 1
!

interface GigabitEthernet0
no ip address
bridge-group 1
duplex auto
speed auto
!
interface Vlan1
no ip address
bridge-group 1
!