6in4 1.9 KB

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  1. .TH 6IN4 8
  2. .SH NAME
  3. 6in4 - configure and run automatic or manual 6to4 tunnel of IPv6 through IPv4
  4. .SH SYNOPSIS
  5. .B ip/6in4
  6. [
  7. .B -ag
  8. ] [
  9. .B -x
  10. .I netmtpt
  11. ] [
  12. .IB local6[ / mask]
  13. [
  14. .I remote4
  15. [
  16. .I remote6
  17. ] ] ]
  18. .SH DESCRIPTION
  19. .I 6in4
  20. sets up and maintains a tunnel of IPv6 traffic through an IPv4 connection.
  21. .I Local6
  22. and
  23. .I mask
  24. define the IPv6 address and subnet of the near end of the tunnel
  25. .RI ( mask
  26. defaults to
  27. .L /128
  28. for a single-host
  29. tunnel),
  30. .I remote4
  31. is the IPv4 address of the far end of the tunnel
  32. (must be given explicitly for a configured tunnel, or
  33. defaults to the anycast address 192.88.99.1 for
  34. .IR 6to4 ),
  35. and
  36. .I remote6
  37. is the IPv6 address of the far end of the tunnel
  38. (used as the point-to-point destination for routing, and
  39. defaults to a link-local address constructed from
  40. .IR remote4 ).
  41. If
  42. .I local6
  43. is missing,
  44. it defaults to
  45. .BI 2002: aabb : ccdd ::1/48 ,
  46. where
  47. .IR aa ,
  48. .IR bb ,
  49. .I cc
  50. and
  51. .I dd
  52. are the hexadecimal equivalents of the bytes
  53. .IB a . b . c .\c
  54. .I d
  55. in this host's primary IPv4 address.
  56. .PP
  57. .I 6in4
  58. forks a pair of background processes to copy packets to and from
  59. the tunnel.
  60. .PP
  61. Supply
  62. .B -g
  63. to use the tunnel as the default route for global IPv6 addresses.
  64. .B -x
  65. uses the network mounted at
  66. .I netmtpt
  67. instead of
  68. .LR /net .
  69. .SH EXAMPLES
  70. If your primary IPv4 address is public,
  71. you can start a 6to4 tunnel simply with
  72. .IP
  73. .EX
  74. 6in4 -g
  75. .EE
  76. .PP
  77. If you use a tunnel broker at address
  78. .LR 5.6.7.8 ,
  79. configured to give you a
  80. .L /64
  81. subnet with address
  82. .LR 2001:1122:3344:5566:: ,
  83. you can start the tunnel with
  84. .IP
  85. .EX
  86. 6in4 -g 2001:1122:3344:5566::/64 5.6.7.8
  87. .EE
  88. .SH FILES
  89. .B /net/ipmux
  90. .SH SEE ALSO
  91. .I ipmux
  92. in
  93. .IR ip (3)
  94. .br
  95. .B /lib/rfc/rfc3056
  96. .br
  97. .B /lib/rfc/rfc3068
  98. .SH BUGS
  99. Needs a kernel with an
  100. .I ipmux
  101. driver.
  102. .PP
  103. The tunnel client filters addresses fairly conservatively in both directions.
  104. However it's not watertight,
  105. and may be flakey in other ways so don't put too much trust in it.