[ovirt-users] NAT in oVirt

I am using oVirt 3.5 and have configured NAT by extnet hooks. I'm suffering this situation: vm: 192.168.122.160 host: 192.168.0.120 gateway: 192.168.0.1 vm can reach outside network but cannot reach host. I've diff an original libvirt vm and a ovirt based vm but I cannot see any obvious difference. Please help me out of this... Thank you very much. This is the NAT configuration. <network> <name>default</name> <uuid>ea0eb0cf-b507-451c-9f0d-919675ea7d8a</uuid> <forward mode='nat'/> <bridge name='virbr0' stp='on' delay='0'/> <mac address='52:54:00:c1:18:e4'/> <ip address='192.168.122.1' netmask='255.255.255.0'> <dhcp> <range start='192.168.122.2' end='192.168.122.254'/> </dhcp> </ip> </network>