pub const K8S_CLUSTER_UID: &str = "k8s.cluster.uid";Expand description
A pseudo-ID for the cluster, set to the UID of the kube-system namespace.
K8s doesn't have support for obtaining a cluster ID. If this is ever
added, we will recommend collecting the k8s.cluster.uid through the
official APIs. In the meantime, we are able to use the uid of the
kube-system namespace as a proxy for cluster ID. Read on for the
rationale.
Every object created in a K8s cluster is assigned a distinct UID. The
kube-system namespace is used by Kubernetes itself and will exist
for the lifetime of the cluster. Using the uid of the kube-system
namespace is a reasonable proxy for the K8s ClusterID as it will only
change if the cluster is rebuilt. Furthermore, Kubernetes UIDs are
UUIDs as standardized by
ISO/IEC 9834-8 and ITU-T X.667.
Which states:
> If generated according to one of the mechanisms defined in Rec. ITU-T X.667 | ISO/IEC 9834-8, a UUID is either guaranteed to be different from all other UUIDs generated before 3603 A.D., or is extremely likely to be different (depending on the mechanism chosen).
Therefore, UIDs between clusters should be extremely unlikely to conflict.
§Examples
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