posix/gai.conf

   1 # Configuration for getaddrinfo(3).
   2 #
   3 # So far only configuration for the destination address sorting is needed.
   4 # RFC 3484 governs the sorting.  But the RFC also says that system
   5 # administrators should be able to overwrite the defaults.  This can be
   6 # achieved here.
   7 #
   8 # All lines have an initial identifier specifying the option followed by
   9 # up to two values.  Information specified in this file replaces the
  10 # default information.  Complete absence of data of one kind causes the
  11 # appropriate default information to be used.  The supported commands include:
  12 #
  13 # reload  <yes|no>
  14 #    If set to yes, each getaddrinfo(3) call will check whether this file
  15 #    changed and if necessary reload.  This option should not really be
  16 #    used.  There are possible runtime problems.  The default is no.
  17 #
  18 # label   <mask>   <value>
  19 #    Add another rule to the RFC 3484 label table.  See section 2.1 in
  20 #    RFC 3484.  The default is:
  21 #
  22 #label ::1/128       0
  23 #label ::/0          1
  24 #label 2002::/16     2
  25 #label ::/96         3
  26 #label ::ffff:0:0/96 4
  27 #label fec0::/10     5
  28 #label fc00::/7      6
  29 #label 2001:0::/32   7
  30 #
  31 #    This default differs from the tables given in RFC 3484 by handling
  32 #    (now obsolete) site-local IPv6 addresses and Unique Local Addresses.
  33 #    The reason for this difference is that these addresses are never
  34 #    NATed while IPv4 site-local addresses most probably are.  Given
  35 #    the precedence of IPv6 over IPv4 (see below) on machines having only
  36 #    site-local IPv4 and IPv6 addresses a lookup for a global address would
  37 #    see the IPv6 be preferred.  The result is a long delay because the
  38 #    site-local IPv6 addresses cannot be used while the IPv4 address is
  39 #    (at least for the foreseeable future) NATed.  We also treat Teredo
  40 #    tunnels special.
  41 #
  42 # precedence  <mask>   <value>
  43 #    Add another rule to the RFC 3484 precedence table.  See section 2.1
  44 #    and 10.3 in RFC 3484.  The default is:
  45 #
  46 #precedence  ::1/128       50
  47 #precedence  ::/0          40
  48 #precedence  2002::/16     30
  49 #precedence ::/96          20
  50 #precedence ::ffff:0:0/96  10
  51 #
  52 #    For sites which prefer IPv4 connections change the last line to
  53 #
  54 #precedence ::ffff:0:0/96  100
  55
  56 #
  57 # scopev4  <mask>  <value>
  58 #    Add another rule to the RFC 6724 scope table for IPv4 addresses.
  59 #    By default the scope IDs described in section 3.2 in RFC 6724 are
  60 #    used.  Changing these defaults should hardly ever be necessary.
  61 #    The defaults are equivalent to:
  62 #
  63 #scopev4 ::ffff:169.254.0.0/112  2
  64 #scopev4 ::ffff:127.0.0.0/104    2
  65 #scopev4 ::ffff:0.0.0.0/96       14