coredns/plugin/log
Miek Gieben d8714e64e4 Remove the word middleware (#1067)
* Rename middleware to plugin

first pass; mostly used 'sed', few spots where I manually changed
text.

This still builds a coredns binary.

* fmt error

* Rename AddMiddleware to AddPlugin

* Readd AddMiddleware to remain backwards compat
2017-09-14 09:36:06 +01:00
..
log.go Remove the word middleware (#1067) 2017-09-14 09:36:06 +01:00
log_test.go Remove the word middleware (#1067) 2017-09-14 09:36:06 +01:00
README.md Remove the word middleware (#1067) 2017-09-14 09:36:06 +01:00
setup.go Remove the word middleware (#1067) 2017-09-14 09:36:06 +01:00
setup_test.go Remove the word middleware (#1067) 2017-09-14 09:36:06 +01:00

log

log enables query logging to standard output.

Syntax

log
  • With no arguments, a query log entry is written to stdout in the common log format for all requests
log FILE
  • FILE is the log file to create (or append to). The only valid name for FILE is stdout.
log [NAME] FILE [FORMAT]
  • NAME is the name to match in order to be logged
  • FILE is the log file (again only stdout is allowed here).
  • FORMAT is the log format to use (default is Common Log Format)

You can further specify the class of responses that get logged:

log [NAME] FILE [FORMAT] {
    class [success|denial|error|all]
}

Here success denial and error denotes the class of responses that should be logged. The classes have the following meaning:

  • success: successful response
  • denial: either NXDOMAIN or NODATA (name exists, type does not)
  • error: SERVFAIL, NOTIMP, REFUSED, etc. Anything that indicates the remote server is not willing to resolve the request.
  • all: the default - nothing is specified.

If no class is specified, it defaults to all.

Log File

The "log file" can only be stdout. CoreDNS expects another service to pick up this output and deal with it, i.e. journald when using systemd or Docker's logging capabilities.

Log Format

You can specify a custom log format with any placeholder values. Log supports both request and response placeholders.

The following place holders are supported:

  • {type}: qtype of the request
  • {name}: qname of the request
  • {class}: qclass of the request
  • {proto}: protocol used (tcp or udp)
  • {when}: time of the query
  • {remote}: client's IP address
  • {size}: request size in bytes
  • {port}: client's port
  • {duration}: response duration
  • {rcode}: response RCODE
  • {rsize}: response size
  • {>rflags}: response flags, each set flag will be displayed, e.g. "aa, tc". This includes the qr bit as well.
  • {>bufsize}: the EDNS0 buffer size advertised in the query
  • {>do}: is the EDNS0 DO (DNSSEC OK) bit set in the query
  • {>id}: query ID
  • {>opcode}: query OPCODE

The default Common Log Format is:

`{remote} - [{when}] "{type} {class} {name} {proto} {size} {>do} {>bufsize}" {rcode} {>rflags} {rsize} {duration}`

Examples

Log all requests to stdout

log stdout

Custom log format, for all zones (.)

log . stdout "{proto} Request: {name} {type} {>id}"

Only log denials for example.org (and below to a file)

log example.org stdout {
    class denial
}