Shipping logs to the logz.io service

Tutorial #logging

Some of you may have heard of Logz.io, a yet-another-company that provides ELK as a Service. Their marketing is quite good, they have great newsletters, tutorials and webcasts, so I thought to myself to let’s check ‘em out. After registration you are taken to the wiki entry that lets you configure your gear to ship your logs logz.io ingest servers. While the wiki looks pretty comprehensive, they evidently missed out the good old Unix player here, syslog-ng. Seeing configuration guides for all these “next-gen”, “cloud-native”, “serverless” totally hyped piece of craps without mentioning syslog-ng at all I feel being kinda old school.

So this post is the missing manual on how to ship logs to logz.io using syslog-ng.

Logz.io uses the all-new RFC5424 “The Syslog Protocol” for transporting the messages, but with a little, out of standard exception: you have to prepend all raw messages with a token that identifies your stream. This is not supported out of the box, so we have to hack around a bit.

For log shipping to work we need two new entries in the syslog-ng.conf.

The first one is the customized RFC5424 lookalike template with your assigned logz.io account token between the []. You can find your token by clicking on the cogwheel (Account) icon on the upper right hand side of the screen. On the appearing page, you can find your token below the Account settings part of the page.

template t_logzio {
  template("[your_account_token_here] <${PRI}>1 $ISODATE $HOST ${PROGRAM} ${PID} - [type=TYPE] ${MSG}\n");
  template_escape(no);
};

Then we need a network type destination driver that makes the TLS connection to logz.io logging stream ingest servers.

destination d_network_logzio {
  network("listener.logz.io" port(5001)
    transport(tls)
    ts-format(rfc3339)
    template(t_logzio)
    flags(no-multi-line)
    tls(
      ca-dir("/etc/syslog-ng/tls/ca.d")
      peer-verify(required-trusted)
      trusted-dn("CN=*.logz.io, OU=PositiveSSL Wildcard, OU=Domain Control Validated")
    )
  );
};

Finally, add the reference to this new destination driver to your existing appropriate log path(es):

log {
  source(s_base);
  source(s_remote);
  [...]
  destination(d_network_logzio);
};

That’s all! Reload syslog-ng and have fun.