Install and Configure Kubernetes (k8s) on ubuntu

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info

这次是18.04  master 58; n1 59; n2 60 #Mon May 27 07:44:35 UTC 2019


每台机器最少2GB内存,2CPUs。
集群中所有机器之间网络连接正常。
打开相应的端口,详见: [ Check required ports https://kubernetes.io/docs/setup/independent/install-kubeadm/#check-required-ports]


Kubernetes要求集群中所有机器具有不同的Mac地址、产品uuid、Hostname。可以使用如下命令查看:

# UUID
 cat /sys/class/dmi/id/product_uuid

# Mac地址
 ip link

# Hostname
 cat /etc/hostname



ubuntu 16.04

master 67  allon vbox 
node1   66  node2   65

https://mirrors.163.com/ubuntu-releases/16.04.6/

使用kubeadm离线部署kubernetesv1.9.0

Set Hostname and update hosts file

sudo hostnamectl set-hostname "k8s-master"
sudo hostnamectl set-hostname k8s-node1
sudo hostnamectl set-hostname k8s-node2

#Add the following lines in /etc/hosts file on all three systems,

192.168.88.30     k8s-master
192.168.88.31     k8s-node1
192.168.88.32    k8s-node2


192.168.88.58     k8s-master #k8sumaster1
192.168.88.59     k8s-node1 #k8sun1
192.168.88.60    k8s-node2 #k8sun2


Ubuntu配置网络和hostname

翻墙

Ubuntu利用shadowsocks和polipo终端翻墙


cat /etc/profile
#这个如何自启动加载呢 不然 notready
export http_proxy="http://127.0.0.1:8123/"
export https_proxy=$http_proxy
#export no_proxy="localhost,127.0.0.1,192.168.88.58,10.96.0.0,10.224.0.0"
 export no_proxy="localhost,127.0.0.1,192.168.88.58,10.96.0.0,10.224.0.0,10.224.*"
 

如果不想翻墙 请参考使用Kubeadm搭建Kubernetes(1.12.2)集群

ins docker

apt-get install docker.io -y #only 4 ubuntu

debian9 or 10

.Install using the repository on debian


apt  install software-properties-common

apt-get remove docker docker-engine docker.io containerd runc

sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    gnupg2 \
    software-properties-common

 curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -

 sudo apt-key fingerprint 0EBFCD88
 sudo add-apt-repository    "deb [arch=amd64] https://download.docker.com/linux/debian \
   $(lsb_release -cs) \
   stable"
 apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io

https://docs.docker.com/install/linux/docker-ce/debian/

2.install-from-a-package on debian

Go to https://download.docker.com/linux/debian/dists/, choose your Debian version, browse to pool/stable/, choose either amd64 or armhf, and download the .deb file for the Docker CE version you want to install.

I am stretch so

apt install libltdl7

http://mirrors.aliyun.com/docker-ce/linux/debian/dists/stretch/pool/stable/amd64/



Docker入门

docker代理设置


#不要少了开头的service 还要记得check一个代理成功不
mkdir -p /etc/systemd/system/docker.service.d
vi /etc/systemd/system/docker.service.d/http-proxy.conf

[Service]
Environment="HTTPS_PROXY=http://127.0.0.1:8123/" "HTTP_PROXY=http://127.0.0.1:8123/" "NO_PROXY=localhost,127.0.0.1,192.168.88.67,10.96.0.0,10.224.0.0"

#Environment="HTTP_PROXY=http://proxy.example.com:80/" "HTTPS_PROXY=http://proxy.example.com:80/""NO_PROXY=localhost,127.0.0.1,docker-registry.somecorporation.com"

systemctl daemon-reload
systemctl restart docker 
systemctl enable docker

systemctl show --property=Environment docker


other
evan@k8s-master:~$ sudo systemctl enable docker 
Synchronizing state of docker.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install enable docker

docker http-proxy

docker 代理设置

docker代理配置-透过代理服务器pull镜像

docker pull 翻墙下载镜像

docker设置代理


docker - 设置HTTP/HTTPS 代理

ins 在所有节点上


swapoff -a;  sudo usermod -a -G docker $USER

apt-get update && apt-get install -y apt-transport-https curl
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF
apt-get update
apt-get install -y kubelet kubeadm kubectl
apt-mark hold kubelet kubeadm kubectl


#init  之前不要启动
#systemctl start kubelet&&  systemctl enable kubelet.service


启动不了
原来是kubelet 的cgroup dirver 与 docker的不一样。docker默认使用cgroupfs,keubelet 默认使用systemd。

https://kubernetes.io/docs/setup/cri/
#这个有改的 18.04上成功了的
vim /etc/systemd/system/kubelet.service.d/10-kubeadm.conf 
[Service]
Environment="KUBELET_AUTHZ_ARGS=--authorization-mode=Webhook --client-ca-file=/etc/kubernetes/pki/ca.crt"
Environment="KUBELET_CADVISOR_ARGS=--cadvisor-port=0"
Environment="KUBELET_CGROUP_ARGS=--cgroup-driver=cgroupfs"

systemctl daemon-reload && systemctl restart kubelet &&  systemctl enable kubelet.service

在 Master 节点上配置 kubelet 所需的 cgroup 驱动

使用 Docker 时,kubeadm 会自动为其检测 cgroup 驱动在运行时对 /var/lib/kubelet/kubeadm-flags.env 文件进行配置。 
如果您使用了不同的 CRI, 您得把 /etc/default/kubelet 文件中的 cgroup-driver 位置改为对应的值,像这样:

KUBELET_EXTRA_ARGS=--cgroup-driver=<value>

这个文件将会被 kubeadm init 和 kubeadm join 用于为 kubelet 获取 额外的用户参数。

请注意,您只需要在您的 cgroup driver 不是 cgroupfs 时这么做,因为 cgroupfs 已经是 kubelet 的默认值了。

systemctl daemon-reload; systemctl restart kubelet #需要重启 kubelet:

#me 
evan@k8s-master:~$ cat /var/lib/kubelet/kubeadm-flags.env 
KUBELET_KUBEADM_ARGS=--cgroup-driver=cgroupfs --network-plugin=cni --pod-infra-container-image=k8s.gcr.io/pause:3.1 --resolv-conf=/run/systemd/resolve/resolv.conf

初始化master

 #14:25:52--14:47:55 kubelet 其实是没启动的 在init之前 
 kubeadm init   --apiserver-advertise-address=192.168.88.30  --pod-network-cidr=10.224.0.0/16 # --apiserver-advertise-address=masterip

kubeadm join 192.168.88.58:6443 --token fuwhe0.ro0c8u82u4xtmn8q \
    --discovery-token-ca-cert-hash sha256:83bd9c19486c44fde674f4ccf0a7382848cd7bfeff8c361d54e7a2955a4dbd60





Alternatively, if you are the root user, you can run:

export KUBECONFIG=/etc/kubernetes/admin.conf



另外有一个小技巧,在init的过程中,另开一个终端,运行

journalctl -f -u kubelet.service

可以查看具体是什么愿意卡住了


 

配置kubectl认证信息

cat  /etc/sudoers.d/evan
echo 'evan ALL=(ALL) NOPASSWD:NOPASSWD:ALL' > /etc/sudoers.d/evan

su - evan 
mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config
echo "source <(kubectl completion bash)" >> ~/.bashrc
exit 

# 对于root用户 这省不能少 不然  #  kubectl  apply -f kube-flannel.yml  The connection to the server localhost:8080 was refused - did you specify the right host or port?

export KUBECONFIG=/etc/kubernetes/admin.conf
#也可以直接放到~/.bash_profile
echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile

安装pod网络on master

  1. 普通用户 不要翻墙
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

添加节点

不要翻墙了 新起个窗口

kubeadm join 192.168.88.58:6443 --token fuwhe0.ro0c8u82u4xtmn8q \
    --discovery-token-ca-cert-hash sha256:83bd9c19486c44fde674f4ccf0a7382848cd7bfeff8c361d54e7a2955a4dbd60 



evan@k8s-master:~$ kubectl get nodes
NAME   STATUS     ROLES    AGE     VERSION
k8s    NotReady   master   5h12m   v1.14.2
u16    NotReady   <none>   106m    v1.14.2

evan@k8s-master:~$ kubectl get pod --all-namespaces
NAMESPACE     NAME                          READY   STATUS              RESTARTS   AGE
kube-system   coredns-fb8b8dccf-nprqq       0/1     Terminating         16         5h11m
kube-system   coredns-fb8b8dccf-qn85f       0/1     Pending             0          5m4s
kube-system   coredns-fb8b8dccf-sgtw4       0/1     Terminating         16         5h11m
kube-system   coredns-fb8b8dccf-wsnkg       0/1     Pending             0          5m5s
kube-system   etcd-k8s                      1/1     Running             0          5h11m
kube-system   kube-apiserver-k8s            1/1     Running             0          5h11m
kube-system   kube-controller-manager-k8s   1/1     Running             0          5h11m
kube-system   kube-flannel-ds-amd64-8vvn6   0/1     Init:0/1            0          107m
kube-system   kube-flannel-ds-amd64-q92vz   1/1     Running             0          112m
kube-system   kube-proxy-85vkt              0/1     ContainerCreating   0          107m
kube-system   kube-proxy-fr7lv              1/1     Running             0          5h11m
kube-system   kube-scheduler-k8s            1/1     Running             0          5h11m


evan@k8s-master:~$ kubectl describe pod  kube-proxy-85vkt  --namespace=kube-system
Name:               kube-proxy-85vkt
Namespace:          kube-system
Priority:           2000001000
PriorityClassName:  system-node-critical
Node:               u16/192.168.88.66
****

Events:
  Type     Reason                  Age                   From               Message
  ----     ------                  ----                  ----               -------
  Normal   Scheduled               109m                  default-scheduler  Successfully assigned kube-system/kube-proxy-85vkt to u16
  Normal   Pulling                 108m                  kubelet, u16       Pulling image "k8s.gcr.io/kube-proxy:v1.14.2"
  Normal   Pulled                  107m                  kubelet, u16       Successfully pulled image "k8s.gcr.io/kube-proxy:v1.14.2"
  Normal   Created                 107m                  kubelet, u16       Created container kube-proxy
  Normal   Started                 107m                  kubelet, u16       Started container kube-proxy
  Warning  FailedCreatePodSandBox  52m (x119 over 107m)  kubelet, u16       Failed create pod sandbox: rpc error: code = Unknown desc = failed pulling image "k8s.gcr.io/pause:3.1": Error response from daemon: Get https://k8s.gcr.io/v2/: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

放了一个晚上 早上还是坏的 突然打开已是好的了

evan@ubuntu18:~$ kubectl get pod --all-namespaces
NAMESPACE     NAME                               READY   STATUS    RESTARTS   AGE
kube-system   coredns-fb8b8dccf-2rbwc            1/1     Running   3          18h
kube-system   coredns-fb8b8dccf-67zc2            1/1     Running   3          18h
kube-system   etcd-ubuntu18                      1/1     Running   10         18h
kube-system   kube-apiserver-ubuntu18            1/1     Running   4          18h
kube-system   kube-controller-manager-ubuntu18   1/1     Running   5          18h
kube-system   kube-flannel-ds-amd64-b6bn8        1/1     Running   45         16h
kube-system   kube-flannel-ds-amd64-v9wxm        1/1     Running   46         16h
kube-system   kube-flannel-ds-amd64-zn4xd        1/1     Running   3          16h
kube-system   kube-proxy-d7pmb                   1/1     Running   4          18h
kube-system   kube-proxy-gcddr                   1/1     Running   0          16h
kube-system   kube-proxy-lv8cb                   1/1     Running   0          16h
kube-system   kube-scheduler-ubuntu18            1/1     Running   5          18h



master 也当作node  这里的master hostname 为	ubuntu18OB
evan@ubuntu18:~$ kubectl  taint node ubuntu18 node-role.kubernetes.io/master-
node/ubuntu18 untainted

#master only
kubectl  taint node ubuntu18 node-role.kubernetes.io/master="":NoSchedule

master 也当作node

 [root@master tomcat]# hostname
master
[root@master tomcat]# kubectl taint node master node-role.kubernetes.io/master-
node/master untainted 


下面的是不是可以不要翻墙了呢

chpater4 k8s architecture

#唯一不是容器形式运行的k8s 组件
evan@k8s-master:~$ sudo systemctl status kubelet.service
● kubelet.service - kubelet: The Kubernetes Node Agent
   Loaded: loaded (/lib/systemd/system/kubelet.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/kubelet.service.d
           └─10-kubeadm.conf
   Active: active (running) since Mon 2019-05-27 07:26:18 UTC; 21min ago
     Docs: https://kubernetes.io/docs/home/
 Main PID: 817 (kubelet)
    Tasks: 19 (limit: 3499)
   CGroup: /system.slice/kubelet.service
           └─817 /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf -



在master节点上发起个创建应用请求 
这里我们创建个名为httpd-app的应用,镜像为httpd,有两个副本pod
evan@k8s-master:~$ kubectl run httpd-app --image=httpd --replicas=2
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.
deployment.apps/httpd-app created

evan@k8s-master:~$ kubectl get deployment
NAME        READY   UP-TO-DATE   AVAILABLE   AGE
httpd-app   0/2     2            0           103s

evan@k8s-master:~$ kubectl get pods -o wide
NAME                         READY   STATUS              RESTARTS   AGE     IP       NODE        NOMINATED NODE   READINESS GATES
httpd-app-6df58645c6-bvg9w   0/1     ContainerCreating   0          2m10s   <none>   k8s-node1   <none>           <none>
httpd-app-6df58645c6-n9xdj   0/1     ContainerCreating   0          2m10s   <none>   k8s-node2   <none>           <none>

evan@k8s-master:~$ kubectl get pods -o wide
NAME                         READY   STATUS              RESTARTS   AGE     IP           NODE        NOMINATED NODE   READINESS GATES
httpd-app-6df58645c6-bvg9w   0/1     ContainerCreating   0          3m58s   <none>       k8s-node1   <none>           <none>
httpd-app-6df58645c6-n9xdj   1/1     Running             0          3m58s   10.224.1.2   k8s-node2   <none>           <none>
#OK了
evan@k8s-master:~$ kubectl get pods -o wide
NAME                         READY   STATUS    RESTARTS   AGE    IP           NODE        NOMINATED NODE   READINESS GATES
httpd-app-6df58645c6-bvg9w   1/1     Running   0          6m8s   10.224.2.3   k8s-node1   <none>           <none>
httpd-app-6df58645c6-n9xdj   1/1     Running   0          6m8s   10.224.1.2   k8s-node2   <none>           <none>

下面 关闭ss docker 代理 polipo

chapter 5 run apps

evan@k8s-master:~$ kubectl run nginx-deployment --image=nginx:1.7.9 --replicas=2
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.
deployment.apps/nginx-deployment created

上面的命令将部署包含两个副本的 Deployment nginx-deployment,容器的 image 为 nginx:1.7.9。

等待一段时间
kubectl get deployment nginx-deployment
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   2/2     2            2           36m


接下来我们用 kubectl describe deployment 了解更详细的信息

等待

sudo  sslocal -c /root/shadowsocks.json -d start
 sslocal -c shadowsocks.json -d start
sslocal -c shadowsocks.json -d start

进阶

K8S 源码探秘 之 kubeadm init 执行流程分析

kubeadm--init

安装k8s Master高可用集群

What is new

在Kubernetes 1.11中,CoreDNS已经实现了基于DNS的服务发现的GA,可作为kube-dns插件的替代品。这意味着CoreDNS将作为各种安装工具未来发布版本中的一个选项来提供。 事实上,kubeadm团队选择将其作为Kubernetes 1.11的默认选项。

CoreDNS正式GA | kube-dns与CoreDNS有何差异?

k8s集群配置使用coredns代替kube-dns

trouble

Kubenetes服务不启动问题

重启系统后,发现kubelet服务没有起来,首先检查:

 1.vim  /etc/fstab
#注释掉里面的swap一行。

2
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf 文件加入KUBELET_CGROUP_ARGS和KUBELET_EXTRA_ARGS参数,


3.注意在启动参数中也要加入,如下:
[Service]

Environment="KUBELET_CGROUP_ARGS=--cgroup-driver=systemd"
Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false"

ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_AUTHZ_ARGS $KUBELET_CADVISOR_ARGS $KUBELET_CERTIFICATE_ARGS $KUBELET_CGROUP_ARGS $KUBELET_EXTRA_ARGS

systemctl daemon-reload
systemctl restart kubelet

trouble2 重启一下机器就坏

为什么重启一下机器就坏了呢

systemctl  status  kubelet
● kubelet.service - kubelet: The Kubernetes Node Agent
   Loaded: loaded (/lib/systemd/system/kubelet.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/kubelet.service.d
           └─10-kubeadm.conf
   Active: activating (auto-restart) (Result: exit-code) since Fri 2019-05-24 20:27:22 CST; 1s ago
     Docs: https://kubernetes.io/docs/home/
  Process: 1889 ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS (cod
 Main PID: 1889 (code=exited, status=255)



kubelet.service: Main process exited, code=exited, status=255


journalctl -xefu kubelet

原来是kubelet 的cgroup dirver 与 docker的不一样。docker默认使用cgroupfs,keubelet 默认使用systemd。


简单地说就是在kubeadm init 之前kubelet会不断重启。


[kubelet-check] Initial timeout of 40s passed.

Unfortunately, an error has occurred:
	timed out waiting for the condition

This error is likely caused by:
	- The kubelet is not running
	- The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)

If you are on a systemd-powered system, you can try to troubleshoot the error with the following commands:
	- 'systemctl status kubelet'
	- 'journalctl -xeu kubelet'


在集群初始化遇到问题,可以使用下面的命令进行清理后重新再初始化:

kubeadm reset
ifconfig cni0 down
ip link delete cni0
ifconfig flannel.1 down
ip link delete flannel.1
rm -rf /var/lib/cni/



K8S 初始化问题,有哪位遇到过,求解!timed out waiting for the condition

trouble3

evan@k8s-master:~$ docker pull gcr.io/kubernetes-helm/tiller:v2.14.0
Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.39/images/create?fromImage=gcr.io%2Fkubernetes-helm%2Ftiller&tag=v2.14.0: dial unix /var/run/docker.sock: connect: permission denied


    sudo usermod -a -G docker $USER #普通用户添加天docker 组

Docker pull Get Permission Denied

trouble 3

docker  223.6.6.6 有时有问题 建议用8.8.4.4

see also

ubuntu 离线搭建Kubenetes1.9.2 集群

使用Kubeadm搭建Kubernetes(1.12.2)集群


Debian 9 使用kubeadm创建 k8s 集群(上)


Debian 9 使用kubeadm创建 k8s 集群(下)


Install and Configure Kubernetes (k8s) 1.13 on Ubuntu 18.04 LTS / Ubuntu 18.10

Ubuntu 18.04 离线安装Kubernetes v1.11.1

安装部署 Kubernetes 集群