[libvirt-users] when save the domain, the following errors occured

Hi, I have create one vm by libvirt api, And I goto virsh, when I doing save the domain, the following errors occurred: virsh # save demo2 /home/wk/libvirt/demo2.save error: Failed to save domain demo2 to /home/wk/libvirt/demo2.save error: internal error unable to send file handle 'migrate': No file descriptor supplied via SCM_RIGHTS virsh # list Id Name State ---------------------------------------------------- 18 demo2 running What was the problem? I cannot find it. Thanks, Kevin.