高可用文档中的坑

1、kube-apiserver、kube-controller-manager启动文件里面的公钥文件、私钥文件竟然是一样的,还怎么配对,这是源文档的大坑


查看源文档kube-apiserver启动文件中公钥

cat etc/systemd/system/kube-apiserver.service

--service-account-key-file=/etc/kubernetes/cert/ca-key.pem


查看源文档kube-controller-manager启动文件中私钥

cat /etc/systemd/system/kube-controller-manager.service

--service-account-private-key-file=/etc/kubernetes/cert/ca-key.pem

发现公钥和私钥都是用的一个私钥,这是不可能配对的,而且原文中已经说明需要配对,说明如下:


原版文件在apiserver启动文字中已经说明 >

--service-account-key-file:签名 ServiceAccount Token 的公钥文件,kube-controller-manager 的 --service-account-private-key-file 指定私钥文件,两者配对使用;

但是原版中apiserver、controller-manager这两个启动文字里面用的私有、公钥都是一个,所以怀疑出错,

按照另一篇对照修改的:https://www.cnblogs.com/effortsing/p/10312081.html,需要修改如下:


生成 service account key

cd /etc/kubernetes/
openssl genrsa -out /etc/kubernetes/sa.key 2048
openssl rsa -in /etc/kubernetes/cert/sa.key -pubout -out /etc/kubernetes/cert/sa.pub
ls /etc/kubernetes/pki/sa.*
cd $HOME

分发service account key到所有master节点

subprocess.call(["ansible k8s -m copy -a 'src=/etc/kubernetes/sa.key dest=/etc/kubernetes/cert/ force=yes'"], shell=True)
subprocess.call(["ansible k8s -m copy -a 'src=/etc/kubernetes/sa.pub dest=/etc/kubernetes/cert/ force=yes'"], shell=True)


修改kube-apiserver启动文件中公钥为sa.pub

cat etc/systemd/system/kube-apiserver.service

--service-account-private-key-file=/etc/kubernetes/cert/sa.pub


修改kube-controller-manager启动文件中私钥为sa.key

cat /etc/systemd/system/kube-controller-manager.service

--service-account-private-key-file=/etc/kubernetes/cert/sa.key




2、源文档kube-controller-manager启动文件里面少两个致命参数,导致flannel启动失败,缺少 --allocate-node-cidrs=true --cluster-cidr=172.30.0.0/16

flannel启动失败,报错如下

Error registering network: failed to acquire lease: node "test4" pod cidr not assigned


查看pod

[root@test4 profile]# kubectl get pods -n kube-system
NAME                    READY   STATUS   RESTARTS   AGE
kube-flannel-ds-gzvrh   0/1     Error    0          <invalid>


通过docker查看flannel日志


[root@test4 profile]# docker ps -l
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
f7be3ebe77fd        b949a39093d6        "/opt/bin/flanneld -…"   1 second ago        Created                                 k8s_kube-flannel_kube-flannel-ds-7cqww_kube-system_26fab004-2b88-11e9-9085-000c2935f634_0

[root@test4 profile]# docker logs f7be3ebe77fd 
I0208 09:58:34.068723       1 main.go:488] Using interface with name ens33 and address 192.168.0.94
I0208 09:58:34.069094       1 main.go:505] Defaulting external address to interface address (192.168.0.94)
I0208 09:58:34.376952       1 kube.go:131] Waiting 10m0s for node controller to sync
I0208 09:58:34.466001       1 kube.go:294] Starting kube subnet manager
I0208 09:58:35.481478       1 kube.go:138] Node controller sync successful
I0208 09:58:35.481666       1 main.go:235] Created subnet manager: Kubernetes Subnet Manager - test4
I0208 09:58:35.481694       1 main.go:238] Installing signal handlers
I0208 09:58:35.482001       1 main.go:353] Found network config - Backend type: vxlan
I0208 09:58:35.482255       1 vxlan.go:120] VXLAN config: VNI=1 Port=0 GBP=false DirectRouting=false
E0208 09:58:35.483159       1 main.go:280] Error registering network: failed to acquire lease: node "test4" pod cidr not assigned
I0208 09:58:35.483433       1 main.go:333] Stopping shutdownHandler...


看到:Error registering network: failed to acquire lease: node "test4" pod cidr not assigned

原因:是因为按照二进制高可用文档安装配置kube-controller-manager启动文件的时候,有坑,当时没有发现,

解决:

启动文件加上下面两句话,那篇文档没有加,所以报错;下面这个cluster-cidr要和kube-flannel.yml里面的地址一致,要和kube-proxy.config.yaml里面的clusterCIDR一致

  --allocate-node-cidrs=true 
  --cluster-cidr=172.30.0.0/16 


4、源文档中的kubelet启动参数中都没有带cadvisor监控服务参数,源文档中就可以访问cadvisor监控了。明摆着安装完把cadvisor参数去掉了,这是大坑



5、执行查看资源报错: unable to upgrade connection: Forbidden (user=kubernetes, verb=create, resource=nodes, subresource=proxy)

[root@test4 ~]# kubectl exec -it http-test-dm2-6dbd76c7dd-cv9qf sh
error: unable to upgrade connection: Forbidden (user=kubernetes, verb=create, resource=nodes, subresource=proxy)

解决:创建apiserver到kubelet的权限

注意:user=kubernetes ,这个user要替换掉下面yaml文件里面的用户名

cat > apiserver-to-kubelet.yaml <<EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: system:kubernetes-to-kubelet
rules:
  - apiGroups:
      - ""
    resources:
      - nodes/proxy
      - nodes/stats
      - nodes/log
      - nodes/spec
      - nodes/metrics
    verbs:
      - "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:kubernetes
  namespace: ""
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:kubernetes-to-kubelet
subjects:
  - apiGroup: rbac.authorization.k8s.io
    kind: User
    name: kubernetes
EOF


创建授权:

kubectl create -f apiserver-to-kubelet.yaml 

[root@test4 ~]# kubectl create -f apiserver-to-kubelet.yaml 
clusterrole.rbac.authorization.k8s.io/system:kubernetes-to-kubelet created
clusterrolebinding.rbac.authorization.k8s.io/system:kubernetes created

重新进到容器查看资源

[root@test4 ~]# kubectl exec -it http-test-dm2-6dbd76c7dd-cv9qf sh
/ # exit

现在可以进到容器里面查看资源了

参照文档:https://www.jianshu.com/p/b3d8e8b8fd7e



6、源文档中kube-apiserver启动参数中没有这句话 --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname

这句话是必须要加的否则用kubectl查看资源、创建dnstools工具时候会报如下错误:

[root@test4 profile]# kubectl run -it --rm --image=infoblox/dnstools dns-client
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
If you don't see a command prompt, try pressing enter.
Error attaching, falling back to logs: error dialing backend: dial tcp 0.0.0.0:10250: connect: connection refused
deployment.apps "dns-client" deleted
Error from server: Get https://test4:10250/containerLogs/default/dns-client-86c6d59f7-tzh5c/dns-client: dial tcp 0.0.0.0:10250: connect: connection refused

[root@test4 ~]# kubectl exec -it http-test-dm2-6dbd76c7dd-cv9qf sh
error: unable to upgrade connection: Forbidden (user=kubernetes, verb=create, resource=nodes, subresource=proxy)
 

7、源文档中kube-apiserver启动参数中--enable-admission-plugins= 这个选项里面的参数很少,导致各种错误,必须填写全,如下:

--enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota 
原文地址:https://www.cnblogs.com/effortsing/p/10356699.html