README
¶
log
log enables query logging.
Syntax
log
- With no arguments, a query log entry is written to query.log in the common log format for all requests
log FILE
- FILE is the log file to create (or append to).
log [NAME] FILE [FORMAT]
NAME
is the name to match in order to be loggedFILE
is the log file to create (or append to)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 responsedenial
: 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 be any filename. It could also be stdout or stderr to write the log to the console, or syslog to write to the system log (except on Windows). If the log file does not exist beforehand, CoreDNS will create it before appending to it.
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.{>bufsize}
: the EDNS0 buffer size advertised.{>do}
: is the EDNS0 DO (DNSSEC OK) bit set.{>id}
: query ID{>opcode}
: query OPCODE.{rcode}
: response RCODE.{rsize}
: response size.
The default Common Log Format is:
`{remote} - [{when}] "{type} {class} {name} {proto} {size} {>do} {>bufsize}" {rcode} {rsize} {duration}`
Examples
Log all requests to a file:
log /var/log/query.log
Custom log format:
log . ../query.log "{proto} Request: {name} {type} {>id}"
Only log denials for example.org (and below to a file)
log example.org example-query-log {
class denial
}
Documentation
¶
Overview ¶
Package log implements basic but useful request (access) logging middleware.
Index ¶
Constants ¶
const ( // DefaultLogFilename is the default log filename. DefaultLogFilename = "query.log" // CommonLogFormat is the common log format. CommonLogFormat = `{remote} ` + CommonLogEmptyValue + ` [{when}] "{type} {class} {name} {proto} {size} {>do} {>bufsize}" {rcode} {rsize} {duration}` // CommonLogEmptyValue is the common empty log value. CommonLogEmptyValue = "-" // CombinedLogFormat is the combined log format. CombinedLogFormat = CommonLogFormat + ` "{>opcode}"` // DefaultLogFormat is the default log format. DefaultLogFormat = CommonLogFormat )
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Logger ¶
type Logger struct { Next middleware.Handler Rules []Rule ErrorFunc func(dns.ResponseWriter, *dns.Msg, int) // failover error handler }
Logger is a basic request logging middleware.