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32 .\" @(#)lo.4 8.1 (Berkeley) 6/5/93
40 .Nd software loopback network interface
46 interface is a software loopback mechanism which may be
47 used for performance analysis, software testing, and/or local
49 As with other network interfaces, the loopback interface must have
50 network addresses assigned for each address family with which it is to be used.
52 may be set or changed with the
55 The loopback interface should be the last interface configured,
56 as protocols may use the order of configuration as an indication of priority.
59 be configured first unless no hardware
63 .It lo%d: can't handle af%d.
64 The interface was handed
65 a message with addresses formatted in an unsuitable address
66 family; the packet was dropped.
78 Previous versions of the system enabled the loopback interface
79 automatically, using a nonstandard Internet address (127.1).
80 Use of that address is now discouraged; a reserved host address
81 for the local network should be used instead.