Leader Elector Extension

Status
Stability	alpha
Distributions	[]
Issues
Code Owners	@dmitryax, @rakesh-garimella

This extension enables OpenTelemetry components to run in HA mode across a Kubernetes cluster. The component that owns the lease becomes the leader and becomes the active instance.

How It Works

The extension uses k8s.io/client-go/tools/leaderelection to perform leader election. The component that owns the lease becomes the leader and runs the function defined in onStartedLeading. If the leader loses the lease, it runs the function defined in onStoppedLeading, stops its operation, and waits to acquire the lease again.

Configuration

receivers:
  my_awesome_receiver:
    k8s_leader_elector: k8s_leader_elector
extensions:
  k8s_leader_elector:
    auth_type: kubeConfig
    lease_name: foo
    lease_namespace: default

service:
  extensions: [k8s_leader_elector]
  pipelines:
    metrics:
      receivers: [my_awesome_receiver]

Leader Election Configuration

configuration	description	default value
auth_type	Authorization type to be used (serviceAccount, kubeConfig).	none (required)
lease_name	The name of the lease object.	none (required)
lease_namespace	The namespace of the lease object.	none (required)
lease_duration	The duration of the lease.	15s
renew_deadline	The deadline for renewing the lease. It must be less than the lease duration.	10s
retry_period	The period for retrying the leader election.	2s

Delete the lease object

kubectl delete leases.coordination.k8s.io -n <namespace> <lease_name>

Suggested RBAC

apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: my-lease
  namespace: default
rules:
- apiGroups:
  - coordination.k8s.io
  resources:
  - leases
  verbs:
  - get
  - list
  - watch
  - create
  - update
  - patch
  - delete