Deployed DNS horizontal autoscaler as an addon

DNS horizontal autoscaling feature is turned on by default on gce.
The corresponding env var is piped into almost all other cloud
providers.

cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml

@@ -0,0 +1,50 @@
+# Copyright 2016 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+apiVersion: extensions/v1beta1
+kind: Deployment
+metadata:
+  name: kube-dns-autoscaler
+  namespace: kube-system
+  labels:
+    k8s-app: kube-dns-autoscaler
+    kubernetes.io/cluster-service: "true"
+spec:
+  template:
+    metadata:
+      labels:
+        k8s-app: kube-dns-autoscaler
+      annotations:
+        scheduler.alpha.kubernetes.io/critical-pod: ''
+        scheduler.alpha.kubernetes.io/tolerations: '[{"key":"CriticalAddonsOnly", "operator":"Exists"}]'
+    spec:
+      containers:
+      - name: autoscaler
+        image: gcr.io/google_containers/cluster-proportional-autoscaler-amd64:1.0.0
+        resources:
+            requests:
+                cpu: "20m"
+                memory: "10Mi"
+        command:
+          - /cluster-proportional-autoscaler
+          - --namespace=kube-system
+          - --configmap=kube-dns-autoscaler
+          - --mode=linear
+          # Should keep target in sync with cluster/addons/dns/skydns-rc.yaml.base
+          - --target=ReplicationController/kube-dns-v20
+          # When cluster is using large nodes(with more cores), "coresPerReplica" should dominate.
+          # If using small nodes, "nodesPerReplica" should dominate.
+          - --default-params={"linear":{"coresPerReplica":256,"nodesPerReplica":16,"min":1}}
+          - --logtostderr=true
+          - --v=2

cluster/addons/dns/skydns-rc.yaml.base

@@ -13,6 +13,8 @@
 # limitations under the License.
 
 # TODO - At some point, we need to rename all skydns-*.yaml.* files to kubedns-*.yaml.*
+# Should keep target in cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml
+# in sync with this file.
 
 # __MACHINE_GENERATED_WARNING__
 

cluster/addons/dns/skydns-rc.yaml.in

@@ -13,6 +13,8 @@
 # limitations under the License.
 
 # TODO - At some point, we need to rename all skydns-*.yaml.* files to kubedns-*.yaml.*
+# Should keep target in cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml
+# in sync with this file.
 
 # Warning: This is a file generated from the base underscore template file: skydns-rc.yaml.base
 

cluster/addons/dns/skydns-rc.yaml.sed

@@ -13,6 +13,8 @@
 # limitations under the License.
 
 # TODO - At some point, we need to rename all skydns-*.yaml.* files to kubedns-*.yaml.*
+# Should keep target in cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml
+# in sync with this file.
 
 # Warning: This is a file generated from the base underscore template file: skydns-rc.yaml.base
 

cluster/aws/config-default.sh

@@ -122,6 +122,9 @@ DNS_SERVER_IP="${DNS_SERVER_IP:-10.0.0.10}"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"
 

cluster/aws/config-test.sh

@@ -108,6 +108,9 @@ DNS_SERVER_IP="${DNS_SERVER_IP:-10.0.0.10}"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"
 

cluster/common.sh

@@ -608,6 +608,7 @@ CLUSTER_REGISTRY_DISK_SIZE: $(yaml-quote ${CLUSTER_REGISTRY_DISK_SIZE:-})
 DNS_REPLICAS: $(yaml-quote ${DNS_REPLICAS:-})
 DNS_SERVER_IP: $(yaml-quote ${DNS_SERVER_IP:-})
 DNS_DOMAIN: $(yaml-quote ${DNS_DOMAIN:-})
+ENABLE_DNS_HORIZONTAL_AUTOSCALER: $(yaml-quote ${ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false})
 KUBELET_TOKEN: $(yaml-quote ${KUBELET_TOKEN:-})
 KUBE_PROXY_TOKEN: $(yaml-quote ${KUBE_PROXY_TOKEN:-})
 ADMISSION_CONTROL: $(yaml-quote ${ADMISSION_CONTROL:-})

cluster/gce/config-default.sh

@@ -115,6 +115,9 @@ DNS_SERVER_IP="${KUBE_DNS_SERVER_IP:-10.0.0.10}"
 DNS_DOMAIN="${KUBE_DNS_DOMAIN:-cluster.local}"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-true}"
+
 # Optional: Install cluster docker registry.
 ENABLE_CLUSTER_REGISTRY="${KUBE_ENABLE_CLUSTER_REGISTRY:-false}"
 CLUSTER_REGISTRY_DISK="${CLUSTER_REGISTRY_PD:-${INSTANCE_PREFIX}-kube-system-kube-registry}"

cluster/gce/config-test.sh

@@ -140,6 +140,9 @@ DNS_SERVER_IP="10.0.0.10"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-true}"
+
 # Optional: Install cluster docker registry.
 ENABLE_CLUSTER_REGISTRY="${KUBE_ENABLE_CLUSTER_REGISTRY:-false}"
 CLUSTER_REGISTRY_DISK="${CLUSTER_REGISTRY_DISK:-${INSTANCE_PREFIX}-kube-system-kube-registry}"

cluster/gce/configure-vm.sh

@@ -442,6 +442,7 @@ enable_cluster_registry: '$(echo "$ENABLE_CLUSTER_REGISTRY" | sed -e "s/'/''/g")
 dns_replicas: '$(echo "$DNS_REPLICAS" | sed -e "s/'/''/g")'
 dns_server: '$(echo "$DNS_SERVER_IP" | sed -e "s/'/''/g")'
 dns_domain: '$(echo "$DNS_DOMAIN" | sed -e "s/'/''/g")'
+enable_dns_horizontal_autoscaler: '$(echo "$ENABLE_DNS_HORIZONTAL_AUTOSCALER" | sed -e "s/'/''/g")'
 admission_control: '$(echo "$ADMISSION_CONTROL" | sed -e "s/'/''/g")'
 storage_backend: '$(echo "$STORAGE_BACKEND" | sed -e "s/'/''/g")'
 network_provider: '$(echo "$NETWORK_PROVIDER" | sed -e "s/'/''/g")'

cluster/gce/coreos/configure-node.sh

@@ -135,6 +135,9 @@ function configure-master-addons() {
 
   if [[ "${ENABLE_CLUSTER_DNS}" == "true" ]]; then
     evaluate-manifests-dir ${MANIFESTS_DIR}/addons/dns ${addon_dir}/dns
+    if [[ "${ENABLE_DNS_HORIZONTAL_AUTOSCALER}" == "true" ]]; then
+      evaluate-manifests-dir ${MANIFESTS_DIR}/addons/dns-horizontal-autoscaler ${addon_dir}/dns-horizontal-autoscaler
+    fi
   fi
 
   if [[ "${ENABLE_CLUSTER_UI}" == "true" ]]; then

cluster/gce/gci/configure-helper.sh

@@ -1025,6 +1025,10 @@ function start-kube-addons {
     sed -i -e "s@{{ *pillar\['dns_domain'\] *}}@${DNS_DOMAIN}@g" "${dns_rc_file}"
     sed -i -e "s@{{ *pillar\['dns_server'\] *}}@${DNS_SERVER_IP}@g" "${dns_svc_file}"
 
+    if [[ "${ENABLE_DNS_HORIZONTAL_AUTOSCALER:-}" == "true" ]]; then
+      setup-addon-manifests "addons" "dns-horizontal-autoscaler"
+    fi
+
     if [[ "${FEDERATION:-}" == "true" ]]; then
       local federations_domain_map="${FEDERATIONS_DOMAIN_MAP:-}"
       if [[ -z "${federations_domain_map}" && -n "${FEDERATION_NAME:-}" && -n "${DNS_ZONE_NAME:-}" ]]; then

cluster/gce/trusty/configure-helper.sh

@@ -869,6 +869,10 @@ start_kube_addons() {
     sed -i -e "s@{{ *pillar\['dns_domain'\] *}}@${DNS_DOMAIN}@g" "${dns_rc_file}"
     sed -i -e "s@{{ *pillar\['dns_server'\] *}}@${DNS_SERVER_IP}@g" "${dns_svc_file}"
 
+    if [[ "${ENABLE_DNS_HORIZONTAL_AUTOSCALER:-}" == "true" ]]; then
+      setup_addon_manifests "addons" "dns-horizontal-autoscaler"
+    fi
+
     if [[ "${FEDERATION:-}" == "true" ]]; then
       FEDERATIONS_DOMAIN_MAP="${FEDERATIONS_DOMAIN_MAP:-}"
       if [[ -z "${FEDERATIONS_DOMAIN_MAP}" && -n "${FEDERATION_NAME:-}" && -n "${DNS_ZONE_NAME:-}" ]]; then

cluster/gke/config-default.sh

@@ -41,4 +41,7 @@ ENABLE_L7_LOADBALANCING="${KUBE_ENABLE_L7_LOADBALANCING:-glbc}"
 #   standalone     - Heapster only. Metrics available via Heapster REST API.
 ENABLE_CLUSTER_MONITORING="${KUBE_ENABLE_CLUSTER_MONITORING:-standalone}"
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 KUBE_DELETE_NETWORK=${KUBE_DELETE_NETWORK:-false}

cluster/libvirt-coreos/config-default.sh

@@ -59,6 +59,9 @@ DNS_SERVER_IP="${SERVICE_CLUSTER_IP_RANGE%.*}.254"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 #Generate dns files
 sed -f "${KUBE_ROOT}/cluster/addons/dns/transforms2sed.sed" < "${KUBE_ROOT}/cluster/addons/dns/skydns-rc.yaml.base" | sed -f "${KUBE_ROOT}/cluster/libvirt-coreos/forShellEval.sed"  > "${KUBE_ROOT}/cluster/libvirt-coreos/skydns-rc.yaml"
 sed -f "${KUBE_ROOT}/cluster/addons/dns/transforms2sed.sed" < "${KUBE_ROOT}/cluster/addons/dns/skydns-svc.yaml.base" | sed -f "${KUBE_ROOT}/cluster/libvirt-coreos/forShellEval.sed"  > "${KUBE_ROOT}/cluster/libvirt-coreos/skydns-svc.yaml"

cluster/mesos/docker/config-default.sh

@@ -34,6 +34,9 @@ DNS_SERVER_IP="10.10.10.10"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Deploy cluster web interface.
 ENABLE_CLUSTER_UI=true
 

cluster/openstack-heat/kubernetes-heat/fragments/configure-salt.yaml

@@ -51,6 +51,7 @@ write_files:
       dns_replicas: "1"
       dns_server: 10.246.0.10
       dns_domain: cluster.local
+      enable_dns_horizontal_autoscaler: "false"
       federations_domain_map: ''
       instance_prefix: kubernetes
       admission_control: NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,DefaultStorageClass,ResourceQuota

cluster/photon-controller/config-default.sh

@@ -79,6 +79,9 @@ DNS_SERVER_IP="10.244.240.240"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI=true
 

cluster/rackspace/config-default.sh

@@ -58,5 +58,8 @@ DNS_SERVER_IP="10.0.0.10"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"

cluster/saltbase/salt/kube-addons/init.sls

@@ -90,6 +90,17 @@ addon-dir-create:
     - makedirs: True
 {% endif %}
 
+{% if pillar.get('enable_dns_horizontal_autoscaler', '').lower() == 'true'
+   and pillar.get('enable_cluster_dns', '').lower() == 'true' %}
+/etc/kubernetes/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml:
+  file.managed:
+    - source: salt://kube-addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml
+    - user: root
+    - group: root
+    - file_mode: 644
+    - makedirs: True
+{% endif %}
+
 {% if pillar.get('enable_cluster_registry', '').lower() == 'true' %}
 /etc/kubernetes/addons/registry/registry-svc.yaml:
   file.managed:

cluster/ubuntu/config-default.sh

@@ -118,6 +118,9 @@ DNS_SERVER_IP=${DNS_SERVER_IP:-"192.168.3.10"}
 DNS_DOMAIN=${DNS_DOMAIN:-"cluster.local"}
 DNS_REPLICAS=${DNS_REPLICAS:-1}
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"
 

cluster/vagrant/config-default.sh

@@ -88,6 +88,9 @@ DNS_SERVER_IP="10.247.0.10"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"
 

cluster/vsphere/config-default.sh

@@ -55,6 +55,9 @@ DNS_SERVER_IP="10.244.240.240"
 DNS_DOMAIN="cluster.local"
 DNS_REPLICAS=1
 
+# Optional: Enable DNS horizontal autoscaler
+ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
+
 # Optional: Install Kubernetes UI
 ENABLE_CLUSTER_UI="${KUBE_ENABLE_CLUSTER_UI:-true}"