The Configuration File

Configuration Elements

For the sake and sanity of the user of this software, we should cover the basic elements of the configuration before getting to the meat and potatoes. There are three basic configuration elements to be concerned about.

  • Configuration Directives
  • Comments
  • Instruction Separator

Configuration Directives

There are five (5) types of configuration directives used with Kamailio.

\Each type of configuration directive uses its own syntax!\
  1. C-Style Control Directives
  2. Apache-Like Name/Value Pairs
  3. Normal Name/Value Pairs
  4. Modify Parameter Procedure
  5. Route Functions

Comments

\The first thing you should understand is the comment syntax used in the configuration file.\

Comments in the configuration file are a mixture of C-Style (not C++) and scripting language syntaxes. It closely resembles the PHP style, except you can not use double-slash ( ⁄ ⁄ ) for line comments. Only the hash (#) may be used for line comments.

It can be confusing seeing the C-Style Control Directives (explained later) that begin with a hash-bang (#!) mixed with line comments beginning with a hash (#).

Examples:
Block Comment:`/* This is a ...
block comment */`
\Not a Comment:\\ // this is NOT a line comment \
Line Comment:# this is a line comment
\Valid Configuration Directive:\#!c_style_directive

Instruction Separator

\Just getting this out of the way before covering the Configuration Directives.\

The semicolon (;) is not required and may be used as an instruction separator for all configuration directives except Route Functions[1].

The general use is to allow for comments or additional configuration directives be placed on the same line.

| Examples: | |------------------------------------------------------------------------| | configuration_directive_a configuration_directive_b; configuration_directive_c; configuration_directive_d configuration_directive_e; # comment about the configuration directive |

Configuration Directives

Type Format Comment
C-Style Control Directives #!directive [ NAME [ VALUE ] ] Begins with hash-bang (#!)
Apache-Like Name/Value Pairs name "value" Delimited by a space & Value within quotes
Normal Name/Value Pairs name=value Delimited by an equals sign
Modify Parameter Procedure modparam("MODULE", "PARAMETER", "VALUE")
Route Functions route Scripting Language

C-Style Control Directives

Available directives:

  • !define NAME - define a keyword

  • !define NAME VALUE - define a keyword with value

  • !ifdef NAME - check if a keyword is defined

  • !ifndef - check if a keyword is not defined

  • !else - swtich to false branch of ifdef/ifndef region

  • !endif - end ifdef/ifndef region

  • !trydef - add a define if not already defined

  • !redefine - force redefinition even if already defined

  • !subst

  • !substdef

Example:
`#!define MODULE_NAME

#!ifdef MODULE_NAME ".. set directives .." #!else ".. set alternate directives .." #!endif ` |

Apache Name/Value Pairs

Syntax
name "value"

\The value MUST be enclosed in quotes.\

| Examples | |-------------------------------------------| | loadmodule "module_name.so" loadmodule "another_module.so" include_file "file_to_include.cfg" import_file "/path/to/file_to_import.cfg" |

Normal Name/Value Pairs

These name/value pairs are normally delimited by an equal sign.

Syntax:
name=value

\There are a couple situations where the value needs to be enclosed in quotes.\ Check the core parameters for the required syntax.

| Examples: | |--------------------------| | memdbg=5 memlog=5 log_facility=LOG_LOCAL0 fork=yes children=4 #disable_tcp=yes auto_aliases=no alias="sip.mydomain.com" |

Modify Parameter Procedure

The modify parameter is similar to other types programming procedure. You call the procedure and it modifies the defined modules parameter.

Syntax:
modparam ( string "$module" , string "$parameter" , mixed "$value" )

\Strings should be enclosed in quotes.\

See the module documentation for support parameter settings.

| Examples: | |---------------------------------------------------------------------------------------| | modparam("first_module", "module_parameter_text", "new_value"); # Set Text Value modparam("second_module", "module_parameter_number", 10000); # Set Numeric Value modparam("second_module", "module_parameter_on", 1); # Enable Parameter modparam("third_module", "module_parameter_on", 0); # Disable Parameter |

Route Functions

I will not go into too much detail here, the scripting methods, functions, and procdedures should be covered elsewhere in this wiki.

| Example: | |-------------------------------------------| | `request_route { route(REQINIT); # Request Initial route(NATDETECT); # NAT Detection

     # CANCEL ??
     if (is_method("CANCEL")) {
      exit;
     }

     # OTHER SCRIPT CODE HERE

}` |

[1] Route Functions use scripting language syntax and must be terminated with a semicolon at the end of each statement.