Sometimes, the plugin states for an output, a filter, and an input plugin should save into in-memory or storage or other key-value stores. Fluentd has a pluggable system called Storage that lets the plugin internal states extract to in-memory or storage or other key-value stores and re-use stored key-value pair value.
For an input, an output, and filter plugin that supports Storage, the
<storage> directive can be used to store key-value pair into the key-vaule store such as json file, MongoDB, Redis and so on.
Here is an example with in_dummy:
<source>@type dummytag docs.fluentd.storage<storage awesome_path>@type my_custom_storage</storage></source>
If this article is incorrect or outdated, or omits critical information, please let us know. Fluentd is a open source project under Cloud Native Computing Foundation (CNCF). All components are available under the Apache 2 License.