6in4 2.3 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. .PP
  22. .I Local6
  23. and
  24. .I mask
  25. define the IPv6 address and subnet of the near end of the tunnel
  26. .RI ( mask
  27. defaults to
  28. .L /128
  29. for a single-host
  30. tunnel).
  31. If
  32. .I local6
  33. is missing or
  34. .LR - ,
  35. it defaults to
  36. .IP
  37. .BI 2002: aabb : ccdd ::1/48
  38. .PP
  39. where
  40. .IR aa ,
  41. .IR bb ,
  42. .I cc
  43. and
  44. .I dd
  45. are the hexadecimal equivalents of the bytes
  46. .IB a . b . c .\c
  47. .I d
  48. in this host's primary IPv4 address.
  49. .PP
  50. .I Remote4
  51. is the IPv4 address of the far end of the tunnel
  52. (must be given explicitly for a configured tunnel, or
  53. defaults to the anycast address 192.88.99.1 for
  54. .IR 6to4 ).
  55. .PP
  56. .I Remote6
  57. is the IPv6 address of the far end of the tunnel
  58. (used as the point-to-point destination for routing, and
  59. defaults to a link-local address constructed from
  60. .IR remote4 ).
  61. .PP
  62. .I 6in4
  63. forks a pair of background processes to copy packets to and from
  64. the tunnel.
  65. .PP
  66. Options are:
  67. .TF -x
  68. .PD 0
  69. .TP
  70. .B -a
  71. permit any remote IPv4 address as the far end of a tunnel.
  72. This is likely to be useful for the server side of a tunnel.
  73. .TP
  74. .B -g
  75. use the tunnel as the default route for global IPv6 addresses
  76. .TP
  77. .B -x
  78. use the network mounted at
  79. .I netmtpt
  80. instead of
  81. .LR /net .
  82. .PD
  83. .SH EXAMPLES
  84. If your primary IPv4 address is public,
  85. you can start a 6to4 tunnel simply with
  86. .IP
  87. .EX
  88. ip/6in4 -g
  89. .EE
  90. .PP
  91. Similarly, you can start a server for
  92. .I 6to4
  93. tunnels with
  94. .IP
  95. .EX
  96. ip/6in4 -ag
  97. .EE
  98. .PP
  99. If you use a tunnel broker at address
  100. .LR 5.6.7.8 ,
  101. configured to give you a
  102. .L /64
  103. subnet with address
  104. .LR 2001:1122:3344:5566:: ,
  105. you can start the tunnel with
  106. .IP
  107. .EX
  108. ip/6in4 -g 2001:1122:3344:5566::/64 5.6.7.8
  109. .EE
  110. .SH FILES
  111. .TF /net/ipmux
  112. .PD 0
  113. .TP
  114. .B /net/ipmux
  115. access to IPv6-in-IPv4 packets
  116. .TP
  117. .B /net/ipifc
  118. packet interface to IPv6 network
  119. .SH SEE ALSO
  120. .IR bridge (3),
  121. .I ipmux
  122. in
  123. .IR ip (3),
  124. .I linklocal
  125. in
  126. .IR ipconfig (8)
  127. .br
  128. .B /lib/rfc/rfc3056
  129. .br
  130. .B /lib/rfc/rfc3068
  131. .SH BUGS
  132. Needs a kernel with an
  133. .I ipmux
  134. driver.
  135. .PP
  136. The tunnel client filters addresses fairly conservatively in both directions.
  137. However it's not watertight,
  138. and may be flakey in other ways so don't put too much trust in it.