Hi everyone, please help me correct the problem. I installed Ubuntu 9.10 Karmic I386 from store first, I started it successfully. I mean I can ping it from outsite and It's always running state. Then I downloaded a Ubuntu 9.10 Karmic iso file from <a href="http://www.ubuntu.com/download">http://www.ubuntu.com/download</a> for bundling. I describe the install process for more detail : 1/ First, I create partition on the host with command, notice that host had bridge with namd br0 runnind as eth0 physical: $ kvm-img create -f qcow2 image.img 5G 2/ Then, copied ubuntu-9.10.iso into /home/lemon1707 to install with command : $ sudo kvm -m 512 -cdrom ubuntu-9.10.iso -drive file=ubuntu9-10.img,if=scsi,index=0,boot=on -boot d -net nic,vlan=0,model=e1000 -net tap -nographic -vnc :0 3/ When the process installation finished : I check the VM ip with ifconfig, It doesn't appear eth0 ip, but in the /etc/network/interfaces it had configurated : auto eth0 iface eth0 inet dhcp 4/ Then I changed bridge='br0' in the file /etc/vmbuilder/libvirt/libvirtxml.tmpl on the host system. After that I relaunched VM with command, The VM's eth0 interface up and VM can connect direct to internet. $ sudo kvm -m 512 -drive file=ubuntu9-10.img,if=scsi,index=0,boot=on -boot c -net nic,vlan=0,model=e1000 -net tap -nographic -vnc :0 5/ I copied initrd.img-2.6.31-14-server and vmlinuz-2.6.31-14-server from VM to host. I registerd it with UEC by using memdisk command. Then I ran it by using Hybridfox, checked the status is running. Public Ip is 192.168.1.100, private ip 172.19.1.2 But I still can not ping or ssh from outsite ( I had opened ports ). The best thing to do is to let VM's interface know where it can bind with the host's bridge interface for VM can connect direct to outsite. Are there any problem in the process ? Should I reinstall because I think we should change bridge='br0' in the file /etc/vmbuilder/libvirt/libvirtxml.tmpl before install VM's OS to make sure they can affect. Any ideas for that problem ? -- Lê Tuấn Nguyền K13t02 <div style="visibility: hidden; left: -5000px; position: absolute; z-index: 9999; padding: 0px; margin-left: 0px; margin-top: 0px; overflow: hidden; word-wrap: break-word; color: black; font-size: 10px; text-align: left; line-height: 130%;" id="avg_ls_inline_popup"> </div>