Mastering Nginx

Appendix A

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Directive Explanation Context/Default

log_subrequest Enables logging of subrequests in

the access log.

Valid contexts: http,

server, location

Default value: off

mail Sets up a configuration context in
which mail server directives are
specified.

Valid context: main

Default value: -

map Defines a new context, in which a

variable is set to a specified value,

dependent on the value of a source

variable. The format of the context

definition is:

map $source-variable

$variable-to-be-set { ... }

The string or strings to be mapped

may also be regular expressions.

The following parameters are

recognized within the context:

• default: Sets a default
  value for the variable if
  the value of the source
  variable didn't match any
  of the strings or regular
  expressions specified


• hostnames: Indicates
  that source values may be
  hostnames with a prefix or
  suffix glob


• include: Includes a
  file with string-to-value
  mappings

Valid context: http

Default value: -

map_hashbucket
size

The bucket size used to hold the

map hash tables.

Valid context: http

Default value:

32|64|128

map_hash_max_size The maximum size of the map

hash tables.

Valid context: http

Default value: 2048

master_process Determines whether or not to start
worker processes.

Valid context: main

Default value: on