---
upgrade:
  - |
    Monasca Log Transformer has been merged with Monasca Log Persister to
    improve performance and reduce resource consumption. Any custom Monasca
    Log Transformer configuration should be either merged into Monasca Log
    Persister configuration, or moved outside of the Monasca pipeline, for
    example, to Fluentd. Any custom Monasca Log Metrics config will also
    need to be updated to read from the raw logs pipeline, rather than the
    transformed logs pipeline. The transformed logs pipeline will be
    removed from Kafka automatically, as will any log transformer containers.
    There will be a short interruption to logging services whilst the
    pipeline is updated. During this time it's likely that a small window
    of logs will be lost from the transformed logs Kafka queue. If this
    is a problem, the Monasca API should be stopped on all nodes prior to
    upgrading Monasca. This will allow the transformed logs topic to drain
    into Elasticsearch before the pipeline is reconfigured. Services such
    as Fluentd, which post logs to the Monasca API, should buffer logs
    whilst this happens up to the maximum configured buffer. Note that
    there may be other services forwarding logs, and these will need to be
    inspected independently. The Log Transformer volumes will remain on
    the monitoring nodes and can be manually removed as described in the
    `documentation
    <https://docs.openstack.org/kolla-ansible/latest/reference/logging-and-monitoring/monasca-guide.html#cleanup>`__.