1ndd(1M)                 System Administration Commands                 ndd(1M)
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NAME

6       ndd - get and set driver configuration parameters
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SYNOPSIS

9       ndd [-set] driver parameter [value]
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DESCRIPTION

13       ndd  gets  and  sets  selected  configuration parameters in some kernel
14       drivers. Currently, ndd only supports the drivers  that  implement  the
15       TCP/IP  Internet  protocol family. Each driver chooses which parameters
16       to make visible using ndd. Since these parameters are  usually  tightly
17       coupled  to  the implementation, they are likely to change from release
18       to release. Some parameters may be read-only.
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21       If the -set option is omitted, ndd queries the named driver,  retrieves
22       the  value  associated  with the specified parameter, and prints it. If
23       the -set option is given, ndd passes value, which  must  be  specified,
24       down to the named driver which assigns it to the named parameter.
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27       By  convention,  drivers  that support ndd also support a special read-
28       only parameter named ``?'' which can be used  to  list  the  parameters
29       supported by the driver.
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EXAMPLES

32       Example 1 Getting Parameters Supported By The TCP Driver
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35       To  see  which parameters are supported by the TCP driver, use the fol‐
36       lowing command:
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39         example% ndd /dev/tcp \?
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44       The parameter name ``?'' may need to be escaped  with  a  backslash  to
45       prevent its being interpreted as a shell meta character.
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49       The  following command sets the value of the parameter ip_forwarding in
50       the dual stack IP driver to zero. This disables IPv4 packet forwarding.
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53         example% ndd -set /dev/ip ip_forwarding 0
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58       Similarly, in order to disable IPv6 packet  forwarding,  the  value  of
59       parameter ip6_forwarding
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62         example% ndd -set /dev/ip ip6_forwarding 0
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ATTRIBUTES

67       See attributes(5) for descriptions of the following attributes:
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72       ┌─────────────────────────────┬─────────────────────────────┐
73       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
74       ├─────────────────────────────┼─────────────────────────────┤
75       │Availability                 │SUNWcsu                      │
76       └─────────────────────────────┴─────────────────────────────┘
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SEE ALSO

79       nca(1),  dladm(1M),  ioctl(2), attributes(5), arp(7P), ip(7P), ip6(7P),
80       tcp(7P), udp(7P)
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NOTES

83       The parameters supported by each driver  may  change  from  release  to
84       release.  Like  programs  that  read  /dev/kmem, user programs or shell
85       scripts that execute ndd should be  prepared  for  parameter  names  to
86       change.
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89       The ioctl() command that ndd uses to communicate with drivers is likely
90       to change in a future release. User programs should avoid making depen‐
91       dencies on it.
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94       The  use  of  ndd  to  administer  Layer 2 (Data Link layer) drivers is
95       strongly discouraged as this capability is to be obsoleted in a  future
96       release, replaced by dladm(1M). Please refer to the driver-specific man
97       page in section 7D of the SunOS man pages.
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100       The meanings of many ndd parameters make sense only if  you  understand
101       how the driver is implemented.
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104       If  a  TCP driver sends a report that is truncated, it could be because
105       that driver uses ndd for transporting  the report. ndd  imposes  a  64K
106       limit on such reports.
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110SunOS 5.11                        13 Mar 2009                          ndd(1M)
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