ipaddrsel(8) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

ipaddrsel(8)

ipaddrsel(8)            System Administration Commands            ipaddrsel(8)

NAME
       ipaddrsel - configure IPv6 default address selection

SYNOPSIS
       /usr/sbin/ipaddrsel


       /usr/sbin/ipaddrsel -f file


       /usr/sbin/ipaddrsel -d

DESCRIPTION
       Use  the ipaddrsel utility to configure the IPv6 default address selec‐
       tion policy table. The policy table is a longest-matching-prefix lookup
       table that is used for IPv6 source address selection and  for  destina‐
       tion address ordering when resolving names to AF_INET6 addresses. For a
       description  of  how the policy table is used for source address selec‐
       tion, see inet6(4P). For a description of how the policy table is  used
       for destination address ordering, see getaddrinfo(3C).


       The  unmodified policy table is valid for all typical IPv6 deployments.
       Modify the table only if a circumstance exists for  which  the  default
       behavior  of  the  IPv6 source address selection or destination address
       ordering mechanism is unsatisfactory. See the Examples section for  ex‐
       amples  of  such  circumstances. You should carefully consider your ad‐
       dressing strategy before you change the table  from  the  provided  de‐
       fault.


       When the ipaddrsel command is issued without any arguments, the address
       selection  policy currently in use is printed. The format of the output
       is compatible with the format of the configuration file that the -f op‐
       tion accepts.

       Note -



         If the usesrc subcommand to ifconfig(8) is applied  to  a  particular
         physical  interface,  the  selection policy specified by usesrc over‐
         rides the source address selection policies specified  by  ipaddrsel.
         This  is true for packets that are locally generated and for applica‐
         tions that do not choose a non-zero source address using bind(3C).


   The Configuration File
       The configuration file that the -f option accepts  can  contain  either
       comment  lines or policy entries. Comment lines have a '#' character as
       the first non-blank character. and they are ignored  by  the  ipaddrsel
       utility. Policy entry lines have the following format:

         prefix/prefix_length precedence label [# comment]



       The prefix must be an IPv6 prefix in a format consistent with inet(3C).
       The  prefix_length is an integer ranging from 0 to 128. The IPv6 source
       address selection and destination address ordering algorithms determine
       the precedence or label of an address by doing  a  longest-prefix-match
       lookup  using the prefixes in this table, much like next-hop determina‐
       tion for a destination is done by doing a  longest-prefix-match  lookup
       using an IP routing table.


       The precedence is a non-negative integer that represents how the desti‐
       nation  address  ordering  mechanism  will sort addresses returned from
       name lookups. In general, addresses with a higher precedence will be in
       front of addresses with a lower precedence. Other factors, such as des‐
       tinations with undesirable  source  addresses  can,  however,  override
       these precedence values.


       The  label is a string of at most fifteen characters, not including the
       NULL terminator. The label allows particular source address prefixes to
       be used with destination prefixes of the same label. Specifically,  for
       a particular destination address, the IPv6 source address selection al‐
       gorithm  prefers source addresses whose label is equal that of the des‐
       tination.


       The label may be followed by an optional comment.


       The file must contain a default policy entry, which is  an  entry  with
       ::0/0  as its prefix and prefix_length. This is to ensure that all pos‐
       sible addresses match a policy.

OPTIONS
       The ipaddrsel utility supports the following options:

       -f file    Replace the address selection policy table with  the  policy
                  specified in the file.


       -d         Revert  the  kernel's address selection policy table back to
                  the default table.  Invoking  ipaddrsel  in  this  way  only
                  changes  the  currently  running  kernel's policy table, and
                  does  not  alter  the  configuration  file   /etc/inet/ipad‐
                  drsel.conf. To revert the configuration file back to its de‐
                  fault settings, use ipaddrsel  -d, then dump the contents of
                  the  table to the configuration file by redirecting the out‐
                  put of ipaddrsel to /etc/inet/ipaddrsel.conf.

                    example# ipaddrsel -d
                    example# ipaddrsel > /etc/inet/ipaddrsel.conf



EXAMPLES
       Example 1 The Default Policy in /etc/inet/ipaddrsel.conf



       The following  example  is  the  default  policy  that  is  located  in
       /etc/inet/ipaddrsel.conf:




         Prefix        Precedence      Label
         ::1/128            50           Loopback (RFC4291)
         ::/0               40           Default
         ::ffff:0:0/96      35           IPv4 ::ffff:0.0.0.0/96 (RFC4038)
         2002::/16          30           6to4 (RFC3056)
         2001::/32           5           Terado (RFC4380)
         fc00::/7            3           Unique Local Addresses (RFC4193)
         ::/96               1           IPv4_Compatible (RFC4291-deprecated)
         fec0::/10           1           Site-local (RFC3879-deprecated)
         3ffe::/16           1           6Bone (RFC3701-deprecated)


       Example 2 Assigning a Lower Precedence to Link-local Addresses



       The destination address selection rules give preference to destinations
       of  smaller scope. For example, a link-local destination will be sorted
       before a global scope destination when the two  are  otherwise  equally
       suitable.  An administrator can change the policy table to reverse this
       preference and sort global destinations before link-local destinations.
       Note: The Link-Local line is added with a Precedence lower than the De‐
       fault prefix (::/0) and therefore lower than global scope addresses:




         Prefix        Precedence      Label
         ::1/128            50           Loopback (RFC4291)
         ::/0               40           Default
         ::ffff:0:0/96      35           IPv4 ::ffff:0.0.0.0/96 (RFC4038)
         fe80::/10          33           Link-Local
         2002::/16          30           6to4 (RFC3056)
         2001::/32           5           Terado (RFC4380)
         fc00::/7            3           Unique Local Addresses (RFC4193)
         ::/96               1           IPv4_Compatible (RFC4291-deprecated)
         fec0::/10           1           Site-local (RFC3879-deprecated)
         3ffe::/16           1           6Bone (RFC3701-deprecated)


       Example 3 Configuring Preference for IPv6 or IPv4



       The default policy table gives IPv6 addresses  higher  precedence  than
       IPv4  addresses.  This means that applications will use IPv6 in prefer‐
       ence to IPv4 when the two are equally suitable.  An  administrator  can
       change  the  policy  table  to  prefer  IPv4  addresses  by  giving the
       ::ffff:0.0.0.0/96 prefix a higher precedence:




         Prefix        Precedence      Label
         ::1/128            50           Loopback (RFC4291)
         ::/0               40           Default
         ::ffff:0:0/96     100           IPv4 ::ffff:0.0.0.0/96 (RFC4038)
         2002::/16          30           6to4 (RFC3056)
         2001::/32           5           Terado (RFC4380)
         fc00::/7            3           Unique Local Addresses (RFC4193)
         ::/96               1           IPv4_Compatible (RFC4291-deprecated)
         fec0::/10           1           Site-local (RFC3879-deprecated)
         3ffe::/16           1           6Bone (RFC3701-deprecated)


       Example 4 Ensuring that a Particular Source Address is Used



       This example ensures that a particular source address is used only when
       communicating with destinations in a particular network. (Assumes there
       are additional ipv6 global scope addresses for use  to  other  destina‐
       tions)



       The following policy table assigns a label of ClientNet to a particular
       source  address  on  the local system, 2001:1111:1111::1. The table as‐
       signs the same label to a network, 2001:2222:2222::/48. The  result  of
       this  policy  is that the 2001:1111:1111::1 source address will only be
       used  when   communicating   with   destinations   contained   in   the
       2001:2222:2222::/48  network.  For  this  example,  this network is the
       ClientNet, which could represent a particular client's network.




         Prefix               Precedence      Label
         ::1/128                   50           Loopback (RFC4291)
         2001:1111:1111::1/128     40           ClientNet
         2001:2222:2222::/48       40           ClientNet
         ::/0                      40           Default
         ::ffff:0:0/96             35           IPv4 ::ffff:0.0.0.0/96 (RFC4038)
         2002::/16                 30           6to4 (RFC3056)
         2001::/32                  5           Terado (RFC4380)
         fc00::/7                   3           Unique Local Addresses (RFC4193)
         ::/96                      1           IPv4_Compatible (RFC4291-deprecated)
         fec0::/10                  1           Site-local (RFC3879-deprecated)
         3ffe::/16                  1           6Bone (RFC3701-deprecated)




       This example assumes that the local system has one physical  interface,
       and that all global prefixes are assigned to that physical interface.

EXIT STATUS
       ipaddrsel returns the following exit values:

       0     ipaddrsel successfully completed.


       >0    An error occurred. If a failure is encountered, the kernel's cur‐
             rent policy table is unchanged.


FILES
       /etc/inet/ipaddrsel.conf    The file that contains the IPv6 default ad‐
                                   dress  selection  policy to be installed at
                                   boot time. This file is loaded  before  any
                                   Internet services are started.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:

       tab()  box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
       TRIBUTE VALUE _ Availabilitysystem/network _ Interface StabilityCommit‐
       ted


SEE ALSO
       getaddrinfo(3C), inet(3C), inet6(4P), ipaddrsel.conf(5), attributes(7),
       nscd(8)

NOTES
       The ipnodes cache kept by nscd(8) contains addresses that  are  ordered
       using  the  destination address ordering algorithm, which is one of the
       reasons why ipaddrsel is called before nscd in the  boot  sequence.  If
       ipaddrsel is used to change the address selection policy after nscd has
       started,  you  should invalidate the nscd ipnodes cache by invoking the
       following command:

         example# /usr/sbin/nscd -i ipnodes


Oracle Solaris 11.4               27 Nov 2017                     ipaddrsel(8)
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3