Worker pool management

Gardener Dashboard

1. Click Settings button as shown on picture below.
2. Click + sign to add worker group.

Continue in pop-up window as shown on image below:

1. Group Name: enter here name of new worker pool
2. Machine Type: select from drop-down menu of currently supported Machine Types, according to your needs
3. Machine Image: select from drop-down menu of currently supported Machine Images, according to your needs
4. Container Runtime: select from drop-down menu of currently supported Container Runtime, according to your needs
5. Volume Size: enter here volume size in GiB
6. Autoscaling configuration:
   1. Autoscaling Min.: enter here minimum number of worker nodes
   2. Autoscaling Min.: enter here maximum number of worker nodes
   3. Max. Surge: enter here max surge
7. Zone: select Availability Zones

Garden Cluster

On the Garden cluster level the Shoot object can be edited (using kubectl edit or kubectl patch) to update worker pool configuration.

Example worker group setup:

apiVersion: core.gardener.cloud/v1beta1
kind: Shoot
spec:
  provider:
    type: onmetal
    # Please note that workers is a list of worker pool configurations.
    workers:
    - name: idp
      cri:
        name: containerd
      machine:
        architecture: amd64
        image:
          name: gardenlinux
          version: 1061.0.20
        type: <machine-class>
      maxSurge: 1
      maxUnavailable: 0
      maximum: 12
      minimum: 12
      systemComponents:
        allow: true
      volume:
        size: 100Gi
        type: fast
      zones:
      - mdb1-pool1
      - mdb2-pool1
      - mdb3-pool1
    # Here an another worker pool configuration can be added

Machine controller advanced settings

There is new section in the Shoot manifest where various timeouts can be configured:

machineCreationTimeout

MachineCreationTimeout is the period after which creation of a Machine is declared as failed.

machineDrainTimeout

MachineDrainTimeout is the period after which a Machine is forcefully deleted.

machineHealthTimeout

MachineHealthTimeout is the period after which a Machine is declared as failed.

maxEvictRetries

MaxEvictRetries are the number of eviction retries on a Pod after which a drain operations is declared as failed, and a forceful deletion is triggered.

nodeConditions

NodeConditions are a set of conditions which, if are true for the period of MachineHealthTimeout, a Machine will be declared as failed.

Example:

kind: Shoot
apiVersion: core.gardener.cloud/v1beta1
metadata:
  name: dash
  namespace: garden-dash
spec:
 …
 provider:
    type: onmetal
    workers:
      - cri:
          name: containerd
          …
        machineControllerManager:
          machineDrainTimeout: 2h0m0s
          machineHealthTimeout: 10m0s
          machineCreationTimeout: 20m0s
          maxEvictRetries: 10
          nodeConditions:
            - ReadonlyFilesystem
            - KernelDeadlock
            - DiskPressure