[Users] oVIrt 3.1 - Network Bonding

Hi, I the attached picture "net1.jpg" i have my initial network configuration. Physical card (em1) with vlan 10 (em1.10) bridged to the ovirtmgmt with IP 192.168.10.25 and default gw 192.168.10.254. Now i want to bond em1 card with p1p1 card (attached picture net2.jpg) But if i fill the default gw it gives me this error: The default gateway should be set only on engine network. If i don't fill the default gw, when i click ok, i loose connection to the server and then after more or less 1 minute the server automaticaly reboots. Anyone had this kind of problem? Best regards, Ricardo Esteves.