semantic-conventions/docs/non-normative/k8s-migration.md

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linkTitle: K8s migration
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# K8s semantic conventions stability migration
Due to the significant number of modifications and the extensive user base
affected by them, existing K8s instrumentations published by
OpenTelemetry are required to implement a migration plan that will assist users in
transitioning to the stable K8s semantic conventions.
When existing K8s instrumentations published by OpenTelemetry are
updated to the stable K8s semantic conventions, they:
- SHOULD introduce an environment variable `OTEL_SEMCONV_STABILITY_OPT_IN` in
their existing major version, which accepts:
- `k8s` - emit the stable k8s conventions, and stop emitting
the old k8s conventions that the instrumentation emitted previously.
- `k8s/dup` - emit both the old and the stable k8s conventions,
allowing for a phased rollout of the stable semantic conventions.
- The default behavior (in the absence of one of these values) is to continue
emitting whatever version of the old k8s conventions the
instrumentation was emitting previously.
- Need to maintain (security patching at a minimum) their existing major version
for at least six months after it starts emitting both sets of conventions.
- May drop the environment variable in their next major version and emit only
the stable k8s conventions.
Specifically for the Opentelemetry Collector:
The transition will happen through two different feature gates.
One for enabling the new schema called `semconv.k8s.enableStable`,
and one for disabling the old schema called `semconv.k8s.disableLegacy`. Then:
- On alpha the old schema is enabled by default (`semconv.k8s.disableLegacy` defaults to false),
while the new schema is disabled by default (`semconv.k8s.enableStable` defaults to false).
- On beta/stable the old schema is disabled by default (`semconv.k8s.disableLegacy` defaults to true),
while the new is enabled by default (`semconv.k8s.enableStable` defaults to true).
- It is an error to disable both schemas
- Both schemas can be enabled with `--feature-gates=-semconv.k8s.disableLegacy,+semconv.k8s.enableStable`.
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- [Summary of changes](#summary-of-changes)
- [K8s network metrics](#k8s-network-metrics)
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## Summary of changes
This section summarizes the changes made to the K8s semantic conventions
from a range of versions. Each starting version shows all the changes required
to bring the conventions to stable (TODO: link to specific version once it exists).
### K8s network metrics
The K8s network metrics implemented by the Collector and specifically the
[kubeletstats](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/v0.112.0/receiver/kubeletstatsreceiver/documentation.md)
receiver were introduced as semantic conventions in [v1.29.0](https://github.com/open-telemetry/semantic-conventions/blob/v1.29.0/docs/system/k8s-metrics.md).
The changes in their attributes are the following:
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| Old (Collector) ![changed](https://img.shields.io/badge/changed-orange?style=flat) | New |
|------------------------------------------------------------------------------------|---------------------------|
| `interface` | `network.interface.name` |
| `direction` | `network.io.direction` |
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