0
votes

I use the skydns-rc.yaml.base(/kubernetes-release-1.3/cluster/addons/dns/sky..) file to create the k8s dns service. but the kubedns container is always failed to created.

the edited element info showed bellow:

namespace : kube-system                                   replaced by       default
PILLAR__DNS__REPLICAS                               replaced by        1
--domain=PILLAR__DNS__DOMAIN.                 replaced by     --domain=cluster.local
PILLAR__FEDERATIONS__DOMAIN__MAP    deleted

the whole skydns-rc.yaml.base template file showed bellow:

apiVersion: v1
kind: ReplicationController
metadata:
  name: kube-dns-v18
  **namespace: kube-system**
  labels:
    k8s-app: kube-dns
    version: v18
    kubernetes.io/cluster-service: "true"
spec:
  replicas: **\_\_PILLAR\_\_DNS\_\_REPLICAS\_\_**
  selector:
    k8s-app: kube-dns
    version: v18
  template:
    metadata:
      labels:
        k8s-app: kube-dns
        version: v18
        kubernetes.io/cluster-service: "true"
    spec:
      containers:
      - name: kubedns
        image: gcr.io/google_containers/kubedns-amd64:1.6
        resources:
          # TODO: Set memory limits when we've profiled the container for large
          # clusters, then set request = limit to keep this container in
          # guaranteed class. Currently, this container falls into the
          # "burstable" category so the kubelet doesn't backoff from restarting it.
          limits:
            cpu: 100m
            memory: 200Mi
          requests:
            cpu: 100m
            memory: 100Mi
        livenessProbe:
          httpGet:
            path: /healthz
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          timeoutSeconds: 5
          successThreshold: 1
          failureThreshold: 5
        readinessProbe:
          httpGet:
            path: /readiness
            port: 8081
            scheme: HTTP
          # we poll on pod startup for the Kubernetes master service and
          # only setup the /readiness HTTP server once that's available.
          initialDelaySeconds: 30
          timeoutSeconds: 5
        args:
        # command = "/kube-dns"
        - --domain=**\_\_PILLAR\_\_DNS\_\_DOMAIN\_\_.**
        - --dns-port=10053
        **\_\_PILLAR\_\_FEDERATIONS\_\_DOMAIN\_\_MAP\_\_**
        ports:
        - containerPort: 10053
          name: dns-local
          protocol: UDP
        - containerPort: 10053
          name: dns-tcp-local
          protocol: TCP
      - name: dnsmasq
        image: gcr.io/google_containers/kube-dnsmasq-amd64:1.3
        args:
        - --cache-size=1000
        - --no-resolv
        - --server=127.0.0.1#10053
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
      - name: healthz
        image: gcr.io/google_containers/exechealthz-amd64:1.0
        resources:
          # keep request = limit to keep this container in guaranteed class
          limits:
            cpu: 10m
            memory: 20Mi
          requests:
            cpu: 10m
            memory: 20Mi
        args:
        - -cmd=nslookup kubernetes.default.svc.**\_\_PILLAR\_\_DNS\_\_DOMAIN\_\_** 127.0.0.1 >/dev/null && nslookup kubernetes.default.svc.**\_\_PILLAR\_\_DNS\_\_DOMAIN\_\_** 127.0.0.1:10053 >/dev/null
        - -port=8080
        - -quiet
        ports:
        - containerPort: 8080
          protocol: TCP
      dnsPolicy: Default  # Don't use cluster DNS.

other info:

the cluster service ip range is 10.254.0.0/16
the domain is cluster.local
namespace is default

After execute statement kubectl describe pod kube-dns-v18 result showed bellow

Name:       kube-dns-v18-u7jgt
Namespace:  default
Node:       centos-cjw-minion1/10.139.4.195
Start Time: Mon, 18 Jul 2016 19:31:48 +0800
Labels:     k8s-app=kube-dns,kubernetes.io/cluster-service=true,version=v18
Status:     Running
IP:     172.17.0.4
Controllers:    ReplicationController/kube-dns-v18
Containers:
  kubedns:
    Container ID:   docker://5f97e1d7185e327ac3cd5415c79b1b51da1987d8946fb243ee1758cdc4d53d29
    Image:      iaasfree/kubedns-amd64:1.5
    Image ID:       docker://sha256:a1490b272781a9921ba216778e741943e9b866114dae7e7e8980daebbc5ba7ed
    Ports:      10053/UDP, 10053/TCP
    Args:
      --domain=cluster.local.
      --dns-port=10053
    QoS Tier:
      memory:   Burstable
      cpu:  Guaranteed
    Limits:
      cpu:  100m
      memory:   200Mi
    Requests:
      cpu:      100m
      memory:       100Mi
    State:      Running
      Started:      Mon, 18 Jul 2016 19:36:02 +0800
    Last State:     Terminated
      Reason:       Error
      Exit Code:    255
      Started:      Mon, 18 Jul 2016 19:34:52 +0800
      Finished:     Mon, 18 Jul 2016 19:35:59 +0800
    Ready:      False
    Restart Count:  3
    Liveness:       http-get http://:8080/healthz delay=60s timeout=5s period=10s #success=1 #failure=5
    Readiness:      http-get http://:8081/readiness delay=30s timeout=5s period=10s #success=1 #failure=3
    Environment Variables:
  dnsmasq:
    Container ID:   docker://75ef5bc18dfe196438956c42f64a2e2d6fd408329408704f32534ce7b9252663
    Image:      iaasfree/kube-dnsmasq-amd64:1.3
    Image ID:       docker://sha256:8cb0646c9e984cf510ca70704154bee2f2c51cfb2e776f4357c52c1d17c2b741
    Ports:      53/UDP, 53/TCP
    Args:
      --cache-size=1000
      --no-resolv
      --server=127.0.0.1#10053
    QoS Tier:
      cpu:      BestEffort
      memory:       BestEffort
    State:      Running
      Started:      Mon, 18 Jul 2016 19:31:55 +0800
    Ready:      True
    Restart Count:  0
    Environment Variables:
  healthz:
    Container ID:   docker://e11626508ecd5b2cfae3e1eaa3284d75dae4160c113d7f28ce97cbd0185f032d
    Image:      iaasfree/exechealthz-amd64:1.0
    Image ID:       docker://sha256:f3b98b5b347af3254c82e3a0090cd324daf703970f3bb62ba8005020ddf5a156
    Port:       8080/TCP
    Args:
      -cmd=nslookup kubernetes.default.svc.cluster.local 127.0.0.1 >/dev/null && nslookup kubernetes.default.svc.cluster.local 127.0.0.1:10053 >/dev/null
      -port=8080
      -quiet
    QoS Tier:
      cpu:  Guaranteed
      memory:   Guaranteed
    Limits:
      memory:   20Mi
      cpu:  10m
    Requests:
      cpu:      10m
      memory:       20Mi
    State:      Running
      Started:      Mon, 18 Jul 2016 19:32:12 +0800
    Ready:      True
    Restart Count:  0
    Environment Variables:
Conditions:
  Type      Status
  Ready     False 
No volumes.
Events:
  FirstSeen LastSeen    Count   From                SubobjectPath           Type        Reason      Message
  --------- --------    -----   ----                -------------           --------    ------      -------
  5m        5m      1   {default-scheduler }                        Normal      Scheduled   Successfully assigned kube-dns-v18-u7jgt to centos-cjw-minion1
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{kubedns}    Normal      Created     Created container with docker id 5814904f6e09
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{dnsmasq}    Normal      Pulled      Container image "iaasfree/kube-dnsmasq-amd64:1.3" already present on machine
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{kubedns}    Normal      Started     Started container with docker id 5814904f6e09
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{dnsmasq}    Normal      Created     Created container with docker id 75ef5bc18dfe
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{dnsmasq}    Normal      Started     Started container with docker id 75ef5bc18dfe
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{healthz}    Normal      Pulled      Container image "iaasfree/exechealthz-amd64:1.0" already present on machine
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{healthz}    Normal      Created     Created container with docker id e11626508ecd
  4m        4m      1   {kubelet centos-cjw-minion1}    spec.containers{healthz}    Normal      Started     Started container with docker id e11626508ecd
  3m        3m      1   {kubelet centos-cjw-minion1}    spec.containers{kubedns}    Normal      Killing     Killing container with docker id 5814904f6e09: pod "kube-dns-v18-u7jgt_default(370b6791-4cdb-11e6-80f0-fa163ebb45ec)" container "kubedns" is unhealthy, it will be killed and re-created.
</code>

After execu statment “kubectl logs kube-dns-v18-yhk41 -c kubedns” showed bellow:

<code>I0719 06:43:41.335795       1 dns.go:172] Ignoring error while waiting for service default/kubernetes: serializer for text/html; charset=utf-8 doesn't exist. Sleeping 1s before retrying.
E0719 06:43:41.335928       1 reflector.go:216] pkg/dns/dns.go:155: Failed to list *api.Service: serializer for text/html; charset=utf-8 doesn't exist
E0719 06:43:41.533705       1 reflector.go:216] pkg/dns/dns.go:154: Failed to list *api.Endpoints: serializer for text/html; charset=utf-8 doesn't exist
I0719 06:43:41.534017       1 dns.go:439] Received DNS Request:kubernetes.default.svc.cluster.local., exact:false
I0719 06:43:41.534048       1 dns.go:539] records:[], retval:[], path:[local cluster svc default kubernetes]
I0719 06:43:42.336756       1 dns.go:172] Ignoring error while waiting for service default/kubernetes: serializer for text/html; charset=utf-8 doesn't exist. Sleeping 1s before retrying.
E0719 06:43:42.336893       1 reflector.go:216] pkg/dns/dns.go:155: Failed to list *api.Service: serializer for text/html; charset=utf-8 doesn't exist
E0719 06:43:42.534553       1 reflector.go:216] pkg/dns/dns.go:154: Failed to list *api.Endpoints: serializer for text/html; charset=utf-8 doesn't exist
1

1 Answers

1
votes

You must set a kube-master-url in args. For example:

    # command = "/kube-dns"
    - --domain=fool.bar.
    - --dns-port=10053
    - --kube-master-url=http://8.9.6.4:8080