Post Installation Guide
This article discusses the post-installation steps for new Fluentd users assuming that Fluentd has been installed using the
td-agent package.After successful installation, a
td-agent instance will be up and running with a predefined template configuration file.The default path for this configuration file is:
/etc/td-agent/td-agent.conf
You may edit this configuration file according to your own use case.
After editing the configuration file, restart
td-agent using systemctl command:$ sudo systemctl restart td-agent
By default,
td-agent writes its operation logs to the following file:/var/log/td-agent/td-agent.log
After the successful installation, a
calyptia-fluentd instance will be up and running with a predefined template configuration file.The default path for this configuration file is:
/etc/calyptia-fluentd/calyptia-fluentd.conf
You may edit this configuration file according to your own use case.
After editing the configuration file, restart
calyptia-fluentd using systemctl command:$ sudo systemctl restart calyptia-fluentd
By default,
calyptia-fluentd writes its operation logs to the following file:/var/log/calyptia-fluentd/calyptia-fluentd.log
In Fluentd, the most important part of data input/output is managed by plugins. Each plugin knows how to interface with an external endpoint and is solely responsible for managing one pipeline to forward data streams.
Plugins use a certain naming convention. For example, if it receives data and interfaces with Apache Kafka, it is called
in_kafka. In the same way, if it publishes data and connects to MongoDB, it is called out_mongo.The following configuration uses the
in_forward plugin as an input source and out_file plugin as an output endpoint:<source>
@type forward
port 9999
</source>
<match app.**>
@type file
path /var/log/app/data.log
compress gzip
</match>
Fluentd manages plugins as Ruby gems but stores them in their dedicated directory separated from the normal Ruby gems.
A special program
td-agent-gem is used to manage plugin gems. For example, the following command installs a plugin to connect to S3 (including both in_s3 and out_s3 plugins): $ sudo /usr/sbin/td-agent-gem install fluent-plugin-s3
A special program
calyptia-fluentd-gem is used to manage plugin gems. For example, the following command installs a plugin to connect to S3 (including both in_s3 and out_s3 plugins): $ sudo /usr/sbin/calyptia-fluentd-gem install fluent-plugin-s3
Note that a number of plugins are bundled with the standard distribution of
td-agent so you do not need to install them manually.A configuration file consists of a number of setting blocks or sections e.g.
<source>. Each block contains a set of options for a specific data endpoint.For example, if you want to create an endpoint to receive data from syslog, you need to add a
<source> block and set up its settings like this:<source>
@type syslog
port 5140
tag system
</source>
The
@type parameter specifies which plugin to use. Note that the plugin type prefix i.e. in_, out_, etc. is not needed here. In this example, the input plugin is specified as syslog, not in_syslog.To add an output endpoint for the data stream, you need to define a
<match> block. Syntactically, <match> is slightly different from <source> in the sense that it requires a filter expression as an argument.For example, if you want to output events tagged with
debug.log, you need to mention this tag as an argument in <match> like this:<match debug.log>
@type kafka2
port 5140
brokers kafka-server:9092
tag system
# ...
</match>
The wildcard character
* can be used in the filter expression. For example, debug.* matches debug.log, debug.foo, etc.To catch all the descendent tags, use double asterisks
**. For example, debug.** matches not only debug.log, but also debug.log.bar or debug.log.level.critical, etc.If this article is incorrect or outdated, or omits critical information, please let us know. Fluentd is an open-source project under Cloud Native Computing Foundation (CNCF). All components are available under the Apache 2 License.
Last modified 1yr ago