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sysconfigtab(4)						      sysconfigtab(4)

  sysconfigtab - Configurable subsystem	definition database file




  The sysconfigtab file	contains initial values	for the	attributes of subsys-
  tems that can	be dynamically configured.  The	information in the syscon-
  figtab file is loaded	into an	in-memory kernel database when the system
  boots.  At subsystem configuration time, values in the in-memory kernel
  database override default values coded into the subsystem.

  There	are multiple numbered versions of the sysconfigtab.* file in the /etc
  directory, but only the /etc/sysconfigtab version is used during normal
  operations. The versions are present to support the dynamic linking of
  modules to create a /vmunix kernel. This feature is called bootlinking and
  is documented	in Guide to Preparing Product Kits. You	may not	be able	to
  use bootlinking if you delete	any copies of the sysconfigtab.* file.

  Avoid	making manual changes to this file.  Instead, use the command syscon-
  figdb(8) to make changes.  This utility will automatically make any changes
  available to the kernel and will preserve the	structure of the file so that
  future upgrades will merge in	correctly.

  The sysconfigtab file	consists of formatted entries. The first line in an
  entry	specifies the subsystem	name.  Subsequent lines	specify	the subsys-
  tems'	attributes and values.	Comment	lines are allowed within an entry.
  The following	shows the syntax of a subsystem	entry:

  subsystem-name: #This	is a comment describing	the subsystem
    attribute1 = value1
    attribute2 = value2, value3

  The following	list details sysconfigtab entries:

    +  The subsystem name is terminated	with a colon (:).

    +  Each attribute name and value pair are terminated with a	newline	char-

    +  Attribute names are separated from values with an equal sign (=).

    +  No space	is allowed in the middle of an attribute name, including an
       array attribute name. For instance, array attribute names such as
       attr1[1]	and attr1[2] are permitted, but	attr1 [1] or attr1[ 2 ]	are
       not. For	example, the following line in /etc/sysconfigtab is permit-
	    attr1[0] = 2

    +  Attributes that have more than one value	separate the values with a
       comma (,).

    +  Quotation marks are not used (")	in string values. Blank	or tab char-
       acters may occur	in the middle of a string, but leading or trailing
       blanks are ignored.

    +  A number	sign (#) appears at the	beginning of comment lines.

       Comments	that are specific to the subsystem are placed after the	line
       containing the subsystem	name.  The sysconfigdb command considers a
       sysconfigtab entry to begin with	the subsystem name and end with
       either the next subsystem name or the end of the	file.  Any comments
       that appear before a subsystem name are considered to be	part of	the
       preceding subsystem and are deleted if the preceding subsystem is

  For a	list of	the subsystem attributes you can configure, see	the System
  Administration manual.  Refer	also to	the various sys_attrs reference
  pages, which list the	system attributes and their default or maximum
  values. The graphical	user interface dxkerneltuner provides you with an
  easy way to review and adjust	attribute values.

  For information about	loadable device	driver attributes, see the Writing
  Device Drivers: Tutorial manual.

  In a cluster environment, an additional clusterwide file,
  sysconfigtab.cluster,	is used	to contain those attributes that must be set
  to the same values in	each member's /etc/sysconfigtab	file.  When a cluster
  member boots,	the contents of	its /etc/sysconfigtab file is synchronized
  against the clusterwide sysconfigtab.cluster file.


  The maximum length of	a stanza entry is 40960	bytes.	An entry cannot	con-
  tain more than 2048 fields (lines).

  The maximum length of	a stanza field is 500 bytes.


  The following	shows an example stanza	entry that could appear	in the confi-
  gurable subsystem database:

		   max-proc-per-user = 64
		   max-threads-per-user	= 256

  The preceding	entry defines the max-proc-per-user and	max-threads-per-user
  attributes for the proc subsystem.


  Commands:  dxkerneltuner(8), sys_attrs(5), sysconfig(8), sysconfigdb(8),

  Files:  stanza(4)

  System Administration
  Writing Device Drivers: Tutorial