Sends log messages to the remote instance of Graylog Server using Graylog Extended Log Format (GELF).

Platforms Supported: All - Requires nuget-package NLog.Targets.Network

This target inherits from the Network Target, and so it has also all the properties of the Network Target available. Using the GelfLayout to produce GELF JSON output.

<targets>
  <target xsi:type="Gelf"
          name="String"
          address="Layout">
    <gelffield name="String" layout="Layout" /><!-- repeated -->
  </target>
</targets>

Read more about using the Configuration File.

• name - Name of the target.

• layout - Instance of GelfLayout that is used to format log messages. Layout Default: GelfLayout

• GelfHostName - Graylog Message Host-field. Default = ${hostname}

• GelfShortMessage - Graylog Message Short-Message-field (Truncates when longer than 250 chars). Default = ${message}

• GelfFullMessage - Graylog Message Full-Message-field. Default = ${message}

• GelfFacility - Legacy Graylog Message Facility-field. Default = null

• IncludeEventProperties - Include all properties from the log events. Default = true.

• IncludeScopeProperties - Include all scope-properties from the ScopeContext. Default = false.

• ExcludeEmptyProperties - Exclude null/empty properties. Default = false.

• ExcludeProperties - Comma separated string with names which properties to exclude.

• IncludeProperties - Comma separated string with names which properties to explicitly include.

• GelfField

  • name - Required. The name of the JSON-key
  • layout - The layout for the JSON-value (Can be a nested JsonLayout)

• encoding - Encoding to be used. Encoding Default: utf-8

• newLine - Indicates whether to append newline at the end of log message. Boolean Default: False

• lineEnding - Line Ending to be used if newLine is set to true. LineEndingMode Default: CRLF. Not used if newLine is false. Possible values:

  • CRLF - Carriage Return and Line Feed (ASCII 13, ASCII 10). (default)
  • CR - Carriage Return (ASCII 13).
  • LF - Line Feed (ASCII 10).
  • NULL - Null terminator (ASCII 0)
  • None - No end of line characters.

• maxMessageSize - Maximum message size in bytes. Integer Default: 65000

• onOverflow - Action that should be taken if the message-size is larger than maxMessageSize. Possible values:

  • Discard - Discard the entire message.
  • Error - Report an error.
  • Split - Split the message into smaller pieces (Default)

• address - Network address. Layout The network address can be:

  • tcp://host:port - TCP (auto select IPv4/IPv6)
  • tcp4://host:port - force TCP/IPv4
  • tcp6://host:port - force TCP/IPv6
  • udp://host:port - UDP (auto select IPv4/IPv6)
  • udp4://host:port - force UDP/IPv4
  • udp6://host:port - force UDP/IPv6
  • http://host:port/pageName - HTTP using POST verb
  • https://host:port/pageName - HTTPS using POST verb

• keepConnection - Indicates whether to keep connection open whenever possible. Boolean Default: True

• connectionCacheSize - Size of the connection cache (number of connections which are kept alive). Integer Default: 5

• maxConnections - Maximum current connections. 0 = no maximum. Integer Default: 16. Not used if keepConnection is true.

• onConnectionOverflow - Action that should be taken when open connections are higher than limit maxConnections.

  Possible enum values:

  • Discard - Discard new messages when reaching limit (Default)
  • Grow - Send message and ignore limit
  • Block - Block until pending connections has been freed.

• maxQueueSize - Maximum queue size for a single connection. 0 means no limit. Integer. Default: 10000

• onQueueOverflow - Action that should be taken if pending queue of messages is larger than maxQueueSize.

  • Discard - Discard the entire message (Default)
  • Grow - Ignore limit and grow the queue.
  • Block - Block until queue is below limit.

• KeepAliveTimeSeconds - Idle time before first TCP keep-alive probe is sent. Faster detection of stale TCP connections. Currently only implemented for TCP. Integer. Default: 0 (Disabled)

• SendTimeoutSeconds - Waiting time before TCP socket send-operation fails with timeout error. Default wait forever when network cable unplugged and tcp-buffer becomes full. Integer. Default: 0 (Disabled)

• NoDelay - Disable the delayed ACK timer, and avoid delay of 200 ms. Default = true.

• sslProtocols - Enables SSL/TLS protocols. Default no SSL/TLS is used. Currently only implemented for TCP. Invalid certificates are not supported. Possible values (combination allowed, comma separated):

  • None - No SSL/TLS is used
  • Default - Accepts Tls or Ssl3
  • Ssl2 - really not recommended
  • Ssl3 - not recommended
  • Tls - TLS 1.0
  • Tls11 - TLS 1.1
  • Tls12 - TLS 1.2

• SslCertificateFile - Enables loading SSL certificate from local file, instead of injecting into operating system cache (Blank value means disable SSL certificate validation)

• SslCertificatePassword - When password is needed for loading SSL certificate from local file using SslCertificateFile

<?xml version="1.0" encoding="utf-8"?>
<nlog throwConfigExceptions="true">

  <targets>
    <target name="graylog" xsi:type="gelf" address="http://localhost:12201/gelf" />
  </targets>

  <rules>
    <logger name="*" minlevel="Trace" writeTo="graylog" />
  </rules>
</nlog>