I have a requirement that the a test server should use the port range 20000 - 22767
I edited the kubeadm-config
with the command
kubectl edit cm kubeadm-config -n kube-system
When I look at the result I see that the change seems to have been stored:
The command $ kubeadm config view
gives me
apiServer:
extraArgs:
authorization-mode: Node,RBAC
service-node-port-range: 20000-22767
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta1
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controlPlaneEndpoint: ""
controllerManager: {}
dns:
type: CoreDNS
etcd:
local:
dataDir: /var/lib/etcd
imageRepository: k8s.gcr.io
kind: ClusterConfiguration
kubernetesVersion: v1.13.3
networking:
dnsDomain: cluster.local
podSubnet: 10.244.0.0/16
serviceSubnet: 10.96.0.0/12
scheduler: {}
But when I later try to install something within hte new port range I get the error
helm upgrade --install --kubeconfig /external-storage/workspace/potapi-orchestration/clusters/at/admin.conf potapi-services charts/potapi-services -f charts/potapi-services/values.at.yaml
Error: UPGRADE FAILED: Service "potapi-services" is invalid: spec.ports[0].nodePort: Invalid value: 21011: provided port is not in the valid range. The range of valid ports is 30000-32767
I have fiddled with the suggestions here but with no luck: https://github.com/kubernetes/kubeadm/issues/122
I too couldn't find any docs on kubeadm configuration. The following works for me:
# your current k8s version
KUBE_VERSION=v1.14.1
KUBEADM_CONFIG=kubeadm-config.yaml
# save current kubeadm config
kubeadm config view > $KUBEADM_CONFIG
# add desired port range
vi kubeadm-config.yaml
apiServer:
extraArgs:
authorization-mode: Node,RBAC
+ service-node-port-range: 20000-22767
# save kubeadm config into a configmap
kubeadm config upload from-file --config $KUBEADM_CONFIG
# check changes
sudo kubeadm upgrade diff --config $KUBEADM_CONFIG
# apply changes
sudo kubeadm upgrade apply $KUBE_VERSION --config $KUBEADM_CONFIG
It is possible to update the service-node-port-range
from it's default values.
I updated the file /etc/kubernetes/manifests/kube-apiserver.yaml
with --service-node-port-range=20000-22767
.
The apiserver was restarted and the port range was updated.
I wrote a blog post about it.