The big change in this release is that Kubernetes service discovery has been completely reworked, so if you were using this service discovery mechanism you'll need to redo your configs and relabelling.
Keeping with service discovery, GCE discovery has additional metadata that can be used in relabelling. A variety of new metrics were also added to the various service discovery mechanisms to aid debugging.
Regex substitution is now done in
target_label in relabelling, in addition to
replacement where it was already available. This will be useful for extracting labels from flat lists.
There's also a variety of smaller fixes and improvements, see the release notes for full details.
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