3.33.1

Highlights

• MQTT destination

  The new mqtt() destination can be used to publish messages using the MQTT protocol.
  Currently MQTT 3.1.1 and 3.1 are supported.

  Supported transports: tcp, ws.

  Example config:

  destination {
    mqtt{
      address("tcp://localhost:1883"),
      topic("syslog/$HOST"),
      fallback-topic("syslog/fallback"))
    };
  };
  

  Note: MQTT 5.0 and TLS (ssl://, wss://) are currently not supported.
  (#3703)

• discord() destination

  syslog-ng now has a webhook-based Discord destination.
  Example usage:

  destination {
    discord(url("https://discord.com/api/webhooks/x/y"));
  };
  

  The following options can be used to customize the destination further:

  avatar-url(), username("$HOST-bot"), tts(true), template("${MSG:-[empty message]}").
  (#3717)

Features

• kafka-c: batching support in case of sync-send(yes)

  kafka-c(
   bootstrap-server("localhost:9092")
   topic("syslog-ng")
   sync-send(yes)
   batch-lines(10)
   batch-timeout(10000)
  );
  

  Note1: batch-lines are accepted in case of sync-send(no), but no batching is done.
  Note2: messages are still sent one at a time to kafka, the batch yields multiple message per transaction.
  (#3699)

• kafka-c: sync-send(yes) enables synchronous message delivery, reducing the possibility of message loss.

  kafka-c(
    bootstrap-server("localhost:9092")
    topic("syslog-ng")
    sync-send(yes)
  );
  

  Warning: this option also reduces significantly the performance of kafka-c driver.
  (#3681)

• disk-buffer: Now we optimize the file truncating frequency of disk-buffer.

  The new behavior saves IO time, but loses some disk space, which is configurable with a new option.
  The new option in the config is settable at 2 places:

  • truncate-size-ratio() in the disk-buffer() block, which affects the given disk-buffer.
  • disk-buffer(truncate-size-ratio()) in the global options block, which affects every disk-buffer
    which did not set truncate-size-ratio() itself.
    The default value is 0.01, which operates well with most disk-buffers.

  If the possible size reduction of the truncation does not reach truncate-size-ratio() x disk-buf-size(),
  we do not truncate the disk-buffer.

  To completely turn off truncating (maximal disk space loss, maximal IO time saved) set truncate-size-ratio(1),
  or to mimic the old behavior (minimal disk space loss, minimal IO time saved) set truncate-size-ratio(0).
  (#3689)

Bugfixes

• syslog-format: fixing the check-hostname(yes|no) option

  The check-hostname(yes|no) option detected every value as invalid, causing a parse error when enabled.
  (#3690)

• disk-buffer(): fix crash when switching between disk-based and memory queues

  When a disk-buffer was removed from the configuration and the new config was
  applied by reloading syslog-ng, a crash occurred.
  (#3700)

• logpath: Fixed a message write protection bug, where message modifications (rewrite rules, parsers, etc.)
  leaked through preceding path elements. This may have resulted not only in unwanted/undefined message modification,
  but in certain cases crash as well.
  (#3708)

• mongodb(): fix crash with older mongo-c-driver versions

  syslog-ng crashed (was aborted) when the mongodb() destination was used with
  older mongo-c-driver versions (< v1.11.0).
  (#3677)

• java(): fix debug logging of Java-based destinations

  Java debug logging was not enabled previously when syslog-ng was started in debug/trace mode. This has been fixed.
  (#3679)

• kafka-c: fixed a hang during shutdown/reload, when multiple workers is used (workers() option is set to 2 or higher) and the librdkafka internal queue is filled.
  (error message was kafka: failed to publish message; topic='test-topic', error='Local: Queue full')
  (#3711)

Packaging

• kafka: minimum version of librdkafka is changed from 1.0.0 to 1.1.0
  (#3706)
• configure: now supporting python with two digit minor version
  (#3713)

Other changes

• kafka: removed some deprecated options: client-lib-dir(), option(), template(), kafka-bootstrap-servers()
  (#3698)
• kafka: properties-file() option is deprecated. Please list the librdkafka properties in the config() option in syslog-ng's configuration.
  (#3698)
• smtp(): libesmtp is now detected via pkg-config
  (#3669)

Credits

syslog-ng is developed as a community project, and as such it relies
on volunteers, to do the work necessarily to produce syslog-ng.

Reporting bugs, testing changes, writing code or simply providing
feedback are all important contributions, so please if you are a user
of syslog-ng, contribute.

We would like to thank the following people for their contribution:

Andras Mitzki, Antal Nemes, Attila Szakacs, Balazs Scheidler,
Balázs Barkó, Benedek Cserhati, Gabor Nagy, L4rS6, Laszlo Budai, Laszlo Szemere,
LittleFish33, László Várady, Norbert Takacs, Peter Czanik, Peter Kokai,
Todd C. Miller, Tomáš Mózes, Zoltan Pallagi