can any one help me???i am in a big trouble while trying to migrate guest in virt manager.

i installed kvm virt-manager nfs and created ssh connection between hosts...
using nfs shared the server directory /var/lib/libvirt/images/ after tried to migrate....then i am getting an error host name can not be resolved...

i've given ip address as hostname and connected using ssh.....
two machines are pinging and nfs sharing also mounted....
please help me........