Change:
### Restrictions <del> - You must create a ConfigMap before referencing it in a Pod specification (unless you mark the ConfigMap as "optional"). If you reference a ConfigMap that doesn't exist, the Pod won't start. Likewise, references to keys that don't exist in the ConfigMap will prevent the pod from starting. </del> <ins> - You must create a ConfigMap before referencing it in a Pod specification, or mark the ConfigMap as "optional" (see [Optional ConfigMaps](#optional-configmaps)). If you reference a ConfigMap that doesn't exist, or hasn't been marked as "optional" the Pod won't start. Likewise, references to keys that don't exist in the ConfigMap will prevent the pod from starting. </ins> - If you use `envFrom` to define environment variables from ConfigMaps, keys that are considered invalid will be skipped. The pod will be allowed to start, but the invalid names will be recorded in the event log (`InvalidVariableNames`). The log message lists each skipped key. For example:

Discussion:
This is a... [x] Bug Report Problem: The documentation mentions "optional" in the restrictions for configmap, but doesn't explain how to use it anywhere else in the documentation. You must create a ConfigMap before referencing it in a Pod specification (unless you mark the ConfigMap as “optional”). If you reference a ConfigMap that doesn’t exist, the Pod won’t start. Likewise, references to keys that don’t exist in the ConfigMap will prevent the pod from starting. Please see for the feature. It appears it got lost in the 1.5-1.6 upgrade. Proposed Solution: Restore the copy from that wrote. Page to Update:
For clarity, the copy from got removed here:
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/language en /remove-lifecycle stale /assign
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/priority backlog
Issues go stale after 90d of inactivity. Mark the issue as fresh with . Stale issues rot after an additional 30d of inactivity and eventually close. If this issue is safe to close now please do so with . Send feedback to sig-testing, kubernetes/test-infra and/or . /lifecycle stale
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If this issue is safe to close now please do so with . Send feedback to sig-testing, kubernetes/test-infra and/or . /lifecycle rotten
/remove-lifecycle stale
/remove-lifecycle rotten
Issues go stale after 90d of inactivity. Mark the issue as fresh with . Stale issues rot after an additional 30d of inactivity and eventually close. If this issue is safe to close now please do so with . Send feedback to sig-testing, kubernetes/test-infra and/or . /lifecycle stale
Relevant to /remove-lifecycle stale
Issues go stale after 90d of inactivity. Mark the issue as fresh with . Stale issues rot after an additional 30d of inactivity and eventually close. If this issue is safe to close now please do so with . Send feedback to sig-testing, kubernetes/test-infra and/or . /lifecycle stale
This awesome feature is still missing in the documentation, Can someone please add it ?
were you thinking of opening a pull request? We'd be happy to help you with that.
/remove-lifecycle stale
/lifecycle frozen
/triage accepted
I don't see any updates; so unassigning you. Please feel free to assign, if you come back here again and are willing to work on it. Thank you! /unassign
/assign