Upgrade Notes

    For more details about changes on each release please refer to the Official Release Notes.

    On Fluent Bit v1.2 we have fixed many issues associated with JSON encoding and decoding, for hence when parsing Docker logs is not longer necessary to use decoders. The new Docker parser looks like this:

    We have done improvements also on how Kubernetes Filter handle the stringified log message. If the option Merge_Log is enabled, it will try to handle the log content as a JSON map, if so, it will add the keys to the root map.

    2.     Name             Kubernetes
    3.     Match            kube.*
    4.     Merge_Log        On
    5.     Merge_Log_Key    log_processed

    As an example, if the original log content is the following map:

    the final record will be composed as follows:

    1. {
    3.     "log_processed": {
    4.         "key1": "val1",
    5.         "key2": "val2"
    6.     }

    Fluent Bit v1.1

    If you are upgrading from Fluent Bit <= 1.0.x you should take in consideration the following relevant changes when switching to Fluent Bit v1.1 series:

    We introduced a new configuration property called Kube_Tag_Prefix to help Tag prefix resolution and address an unexpected behavior that landed in previous versions.

    The expected behavior is that Tag will be expanded to:

    1. kube.var.log.containers.apache.log

    but the change introduced in 1.0 series switched from absolute path to the base file name only:

    On Fluent Bit v1.1 release we restored to our default behavior and now the Tag is composed using the absolute path of the monitored file.

    Having absolute path in the Tag is relevant for routing and flexible configuration where it also helps to keep compatibility with Fluentd behavior.

    2.     Name  tail
    3.     Path  /var/log/containers/*.log
    4.     Tag   kube.*
    6. [FILTER]
    7.     Name             kubernetes
    8.     Kube_Tag_Prefix  kube.var.log.containers.

    So the proper for Kube_Tag_Prefix value must be composed by Tag prefix set in Tail input plugin plus the converted monitored directory replacing slashes with dots.