Network performance tuning with the no command

The network option or no command displays, changes, and manages the global network options.

The following no command options are used to change the tuning parameters:

Option: Definition
-a: Prints all tunables and their current values.
-d [tunable]: Sets the specified tunable back to the default value.
-D: Sets all options back to their default values.
-o tunable=[New Value]: Displays the value or sets the specified tunable to the specified new value
-h [tunable]: Displays help about the specified tunable parameter, if one is specified. Otherwise, displays the no command usage statement.
-r: Used with the -o option to change a tunable that is of type Reboot to be permanent in the nextboot file.
-p: Used with the -o option to make a dynamic tunable permanent in the nextboot file.
-L [tunable]: Used with the -o option to list the characteristics of one or all tunables, one per line.

The following is an example of the no command:

NAME                      CUR    DEF    BOOT   MIN    MAX    UNIT           TYPE     DEPENDENCIES

-------------------------------------------------------------------------------------------------

General Network Parameters

-------------------------------------------------------------------------------------------------
sockthresh                85     85     85     0      100    %_of_thewall      D
-------------------------------------------------------------------------------------------------
fasttimo                  200    200    200    50     200    millisecond       D
-------------------------------------------------------------------------------------------------
inet_stack_size           16     16     16     1             kbyte             R
-------------------------------------------------------------------------------------------------
...lines omitted....


where:
CUR = current value

DEF = default value

BOOT = reboot value

MIN = minimal value

MAX = maximum value

UNIT = tunable unit of measure

TYPE = parameter type: D (for Dynamic), S (for Static), R for Reboot),B (for Bosboot), M (for Mount),
                       I (for Incremental) and C (for Connect)

DEPENDENCIES = list of dependent tunable parameters, one per line

Some network attributes are run-time attributes that can be changed at any time. Others are load-time attributes that must be set before the netinet kernel extension is loaded.

Note: When you use the no command to change parameters, dynamic parameters are changed in memory and the change is in effect only until the next system boot. At that point, all parameters are set to their reboot settings. To make dynamic parameter changes permanent, use the -ror -p options of the no command to set the options in the nextboot file. Reboot parameter options require a system reboot to take affect.

For more information on the no command, see The no Command in Commands Reference, Volume 4.