log_format

Specifies log format.

The escape parameter (1.11.8) allows setting json or default characters escaping in variables, by default, default escaping is used.

The log format can contain common variables, and variables that exist only at the time of a log write:

$bytes_sent

the number of bytes sent to a client

$connection

connection serial number

$connection_requests

the current number of requests made through a connection (1.1.18)

$msec

time in seconds with a milliseconds resolution at the time of the log write

$pipe

“p” if request was pipelined, “.” otherwise

$request_length

request length (including request line, header, and request body)

$request_time

request processing time in seconds with a milliseconds resolution; time elapsed between the first bytes were read from the client and the log write after the last bytes were sent to the client

$status

response status

$time_iso8601

local time in the ISO 8601 standard format

$time_local

local time in the Common Log Format

In the modern nginx versions variables $status (1.3.2, 1.2.2), $bytes_sent (1.3.8, 1.2.5), $connection (1.3.8, 1.2.5), $connection_requests (1.3.8, 1.2.5), $msec (1.3.9, 1.2.6), $request_time (1.3.9, 1.2.6), $pipe (1.3.12, 1.2.7), $request_length (1.3.12, 1.2.7), $time_iso8601 (1.3.12, 1.2.7), and $time_local (1.3.12, 1.2.7) are also available as common variables.

Header lines sent to a client have the prefix “sent_http_”, for example, $sent_http_content_range.

The configuration always includes the predefined “combined” format:

log_format combined '$remote_addr - $remote_user [$time_local] '
                    '"$request" $status $body_bytes_sent '
                    '"$http_referer" "$http_user_agent"';