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

       ndd - get and set driver	configuration parameters

       ndd [-set] driver parameter [value]

       ndd  gets  and  sets  selected  configuration parameters	in some	kernel
       drivers.	Currently, ndd only supports the drivers  that	implement  the
       TCP/IP  Internet	 protocol family. Each driver chooses which parameters
       to make visible using ndd. Since	these parameters are  usually  tightly
       coupled	to  the	implementation,	they are likely	to change from release
       to release. Some	parameters may be read-only.

       If the -set option is omitted, ndd queries the named driver,  retrieves
       the  value  associated  with the	specified parameter, and prints	it. If
       the -set	option is given, ndd passes value, which  must	be  specified,
       down to the named driver	which assigns it to the	named parameter.

       By  convention,	drivers	 that support ndd also support a special read-
       only parameter named ``?'' which	can be used  to	 list  the  parameters
       supported by the	driver.

       Example 1: Getting Parameters Supported By The TCP Driver

       To  see which parameters	are supported by the TCP driver,  use the fol-
       lowing command:

       example%	ndd /dev/tcp \?

       The parameter name ``?''	may need to be escaped	with  a	 backslash  to
       prevent its being interpreted as	a shell	meta character.

       The following command sets the value of the parameter  ip_forwarding in
       the dual	stack IP driver	to zero. This disables IPv4 packet forwarding.

       example%	ndd -set /dev/ip ip_forwarding 0

       Similarly, in order to disable IPv6 packet forwarding, the value	of pa-
       rameter ip6_forwarding

       example%	ndd -set /dev/ip ip6_forwarding	0

       To view the current IPv4	forwarding table, use the following command:

       example%	ndd /dev/ip ipv4_ire_status

       To view the current IPv6	forwarding table, use the following command:

       example%	ndd /dev/ip ipv6_ire_status

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcsu			   |

       nca(1),	ioctl(2),  attributes(5),  arp(7P),  ip(7P), ip6(7P), tcp(7P),

       The parameters supported	by each	driver may change from release to  re-
       lease.  Like  programs  that  read  /dev/kmem,  user  programs or shell
       scripts that execute ndd	should be  prepared  for  parameter  names  to

       The ioctl() command that	ndd uses to communicate	with drivers is	likely
       to change in a future release. User programs should avoid making	depen-
       dencies on it.

       The  meanings  of many ndd parameters make sense	only if	you understand
       how the driver is implemented.

SunOS 5.9			  8 Nov	1999			       ndd(1M)


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