7.2. elasticsearch: Sending messages directly to Elasticsearch version 1.x

Starting with version 3.7 of syslog-ng OSE can directly send log messages to Elasticsearch, allowing you to search and analyze your data in real time, and visualize it with Kibana.

Note the following limitations when using the syslog-ng OSE elasticsearch destination:

  • This destination is only supported on the Linux platform.

  • Since syslog-ng OSE uses the official Java Elasticsearch libraries, the elasticsearch destination has significant memory usage.

  • Sending messages over the HTTP REST API is supported only using the elastic2() destination. Note that in HTTP mode, the elasticsearch2 destination can send log messages to Elasticsearch version 1.x and newer. For details, see Section 7.3, elasticsearch2: Sending messages directly to Elasticsearch version 2.0 or higher.

  • The log messages of the underlying client libraries are available in the internal() source of syslog-ng OSE.

Declaration: 

@module mod-java
@include "scl.conf"

elasticsearch(
    index("syslog-ng_${YEAR}.${MONTH}.${DAY}")
    type("test")
    cluster("syslog-ng")
);
Example 7.4. Sending log data to Elasticsearch version 1.x

The following example defines an elasticsearch destination that sends messages in transport mode to an Elasticsearch server version 1.x running on the localhost, using only the required parameters.

@module mod-java
@include "scl.conf"

destination d_elastic {
  elasticsearch(
    index("syslog-ng_${YEAR}.${MONTH}.${DAY}")
    type("test")
  );
};

The following example sends 10000 messages in a batch, in transport mode, and includes a custom unique ID for each message.

@module mod-java
@include "scl.conf"

options {
  threaded(yes);
  use-uniqid(yes);
};

source s_syslog {
  syslog();
};

destination d_elastic {
  elasticsearch(
    index("syslog-ng_${YEAR}.${MONTH}.${DAY}")
    type("test")
    cluster("syslog-ng")
    client-mode("transport")
    custom-id("${UNIQID}")
    flush-limit("10000")
  );
};

log {
  source(s_syslog);
  destination(d_elastic);
  flags(flow-control);
};

The elasticsearch() driver is actually a reusable configuration snippet configured to receive log messages using the Java language-binding of syslog-ng OSE. For details on using or writing such configuration snippets, see Section 5.6.2, Reusing configuration blocks. You can find the source of the elasticsearch configuration snippet on GitHub. For details on extending syslog-ng OSE in Java, see the Getting started with syslog-ng development guide.