I have a physical Server with two NICs eth0 and eth1. 
        
        
        
        I am running Xen 4.4.1 with Debian Jesse.
        
        
        eth0 is bridged to xenbr0 which receives it's IP address,
          dns etc through an upstream DHCP server on a Gateway.
        
        
        eth1 is bridged to xenbr1
        
        
        I am creating a Xen VM (DomU) with two virtual interfaces
          that are bridged to xenbr0 & xenbr1 respectively. 
        
        
        I want to run a router + NAT configuration on that DomU. 
        
        
        I have several computers connected to eth1 through a
          physical managed switch.
        
        
        I want computers connected to eth1 access the internet.
        
        
        I want other DomU VMs to also use DomU as a router and
          access the internet. 
        
        
        
        
        Gateway <-> eth0 <-> xenbr0 <-> vif0 
        
        
        eth1 <-> xenbr1 <-> vif1 <-> Switch
          <-> Computers
        
        
        
        
        So far I've created the DomU and IPTables on it so that
          computers connected to the switch on eth1 are able to ping
          each other.
        
        
        I am unable to traverse from the computers connected to the
          switch on eth1 to the internet. 
        
        
        How do I bridge the traffic from eth1 to eth0? 
        Do I need to setup forwarding or IPTables on Dom0? 
        How do I setup DomU as the router and Gateway for other
          DomU VMs?
        
        
        Thanks!