root@vnet:~# ifconfig lo ::1
::1: Unknown host
Usage:
  ifconfig [-a] [-i] [-v] <interface> [[<AF>] <address>]
  [add <address>[/<prefixlen>]]
  [del <address>[/<prefixlen>]]
  [[-]broadcast [<address>]]  [[-]pointopoint [<address>]]
  [netmask <address>]  [dstaddr <address>]  [tunnel <address>]
  [outfill <NN>] [keepalive <NN>]
  [hw <HW> <address>]  [metric <NN>]  [mtu <NN>]
  [[-]trailers]  [[-]arp]  [[-]allmulti]
  [multicast]  [[-]promisc]
  [mem_start <NN>]  [io_addr <NN>]  [irq <NN>]  [media <type>]
  [txqueuelen <NN>]
  [[-]dynamic]
  [up|down] ...

  <HW>=Hardware Type.
  List of possible hardware types:
    loop (Local Loopback) slip (Serial Line IP) cslip (VJ Serial Line IP)
    slip6 (6-bit Serial Line IP) cslip6 (VJ 6-bit Serial Line IP) adaptive (Adaptive Serial Line IP)
    ether (Ethernet) tr (16/4 Mbps Token Ring) tr (16/4 Mbps Token Ring (New))
    ax25 (AMPR AX.25) netrom (AMPR NET/ROM) tunnel (IPIP Tunnel)
    ppp (Point-to-Point Protocol) arcnet (ARCnet) dlci (Frame Relay DLCI)
    frad (Frame Relay Access Device) irda (IrLAP)
  <AF>=Address family. Default: inet
  List of possible address families:
    unix (UNIX Domain) inet (DARPA Internet) ax25 (AMPR AX.25)
    netrom (AMPR NET/ROM) ipx (Novell IPX) ddp (Appletalk DDP)
root@vnet:~#