Hello ! Just a little mistake in prometheus installation with helm, the --set alertmanager.persistentVolume.storageClass="gp2" is not ok, the good one is : -set alertmanager.persistence.storageClass="gp2" If not the storage class of alertmanager is not set to "gp2" and it's not enable to mount. so it's : helm upgrade -i prometheus prometheus-community/prometheus \ --namespace prometheus \ --set alertmanager.persistence.storageClass="gp2" \ --set server.persistentVolume.storageClass="gp2"