I've tested some functions of libvirt don't work. Could some people give me a reasonable explanation about these functions? Why do these function don't work? Or if there is anything wrong of my understanding.

virsh # migrate 1 xen+ssh://root@172.16.201.183/

Password:

error: POST operation failed: xend_post: error from xen daemon: (xend.err "can't connect: (-2, 'Name or service not known')")

virsh # dommemstat 5

error: Failed to get memory statistics for domain 5

error: this function is not ! supported by the hypervisor: virDomainMemoryStats

virsh # dump 5 file

error: Failed to core dump domain 5 to file

error: POST operation failed: xend_post: error from xen daemon: (xend.err 'Too many values for live')

virsh # iface-list

error: Failed to list active interfaces

error: this function is not supported by the hypervisor: virConnectNumOfInterfaces

virsh # vncdisplay 5

virsh # vncdisplay 41

virsh # snapshot-create 42 snapshot.xml

error: Failed to create snapshot snapshot.xml for domain 42

NWFILTER functions

Thank you very ! much!