0. 介绍
最近在准备 CKA 考试，所以需要搭建一个 Kubernetes 集群来方便练习．GCP 平台新用户注册送 300 刀体验金，所以就想到用 kubeadm 在 GCP 弄个练练手，既方便又省钱．
这一套做下来，还是比较容易上手的，kubeadm 提供的是傻瓜式的安装体验，所以难度主要还是在科学上网和熟悉 GCP 的命令上，接下来就详细记述一下如何操作．
1. 准备
接下来的操作都假设已经设置好了科学上网，由于政策原因，具体做法请自行搜索；而且已经注册好了 GCP 账户，链接如下：GCP
1.1 gcloud 安装和配置
首先需要在本地电脑上安装 GCP 命令行客户端：gcloud，参考链接为：gcloud
因为众所周知的原因，gcloud 要能正常使用，要设置代理才可以，下面是设置 SOCKS5 代理的命令：
# gcloud config set proxy/type PROXY_TYPE
$ gcloud config set proxy/type socks5
# gcloud config set proxy/address PROXY_IP_ADDRESS
$ gcloud config set proxy/address 127.0.0.1
# gcloud config set proxy/port PROXY_PORT
$ gcloud config set proxy/address 1080如果是第一次使用 GCP，需要先进行初始化．在初始化的过程中会有几次交互，使用默认选项即可．由于之前已经设置了代理，网络代理相关部分就可以跳过了．
注意：在选择 region（区域）时，建议选择 us-west2，原因是目前大部分 GCP 的 region，体验用户只能最多创建四个虚拟机实例，只有少数几个区域可以创建六个，其中就包括 us-west2，正常来讲，搭建 Kubernetes 需要三个 master，三个 worker，四个不太够用，当然如果只是试试的话，两个节点，一主一从，也够用了．
$ gcloud init
Welcome! This command will take you through the configuration of gcloud.
Settings from your current configuration [profile-name] are:
core:
disable_usage_reporting: 'True'
Pick configuration to use:
[1] Re-initialize this configuration [profile-name] with new settings
[2] Create a new configuration
[3] Switch to and re-initialize existing configuration: [default]
Please enter your numeric choice: 3
Your current configuration has been set to: [default]
You can skip diagnostics next time by using the following flag:
gcloud init --skip-diagnostics
Network diagnostic detects and fixes local network connection issues.
Checking network connection...done.
ERROR: Reachability Check failed.
Cannot reach https://www.google.com (ServerNotFoundError)
Cannot reach https://accounts.google.com (ServerNotFoundError)
Cannot reach https://cloudresourcemanager.googleapis.com/v1beta1/projects (ServerNotFoundError)
Cannot reach https://www.googleapis.com/auth/cloud-platform (ServerNotFoundError)
Cannot reach https://dl.google.com/dl/cloudsdk/channels/rapid/components-2.json (ServerNotFoundError)
Network connection problems may be due to proxy or firewall settings.
Current effective Cloud SDK network proxy settings:
type = socks5
host = PROXY_IP_ADDRESS
port = 1080
username = None
password = None
What would you like to do?
[1] Change Cloud SDK network proxy properties
[2] Clear all gcloud proxy properties
[3] Exit
Please enter your numeric choice: 1
Select the proxy type:
[1] HTTP
[2] HTTP_NO_TUNNEL
[3] SOCKS4
[4] SOCKS5
Please enter your numeric choice: 4
Enter the proxy host address: 127.0.0.1
Enter the proxy port: 1080
Is your proxy authenticated (y/N)? N
Cloud SDK proxy properties set.
Rechecking network connection...done.
Reachability Check now passes.
Network diagnostic (1/1 checks) passed.
You must log in to continue. Would you like to log in (Y/n)? y
Your browser has been opened to visit:
https://accounts.google.com/o/oauth2/auth?redirect_uri=......
已在现有的浏览器会话中创建新的窗口。
Updates are available for some Cloud SDK components. To install them,
please run:
$ gcloud components update
You are logged in as: [<gmail account>].
Pick cloud project to use:
[1] <project-id>
[2] Create a new project
Please enter numeric choice or text value (must exactly match list
item): 1
Your current project has been set to: [<project-id>].
Your project default Compute Engine zone has been set to [us-west2-b].
You can change it by running [gcloud config set compute/zone NAME].
Your project default Compute Engine region has been set to [us-west2].
You can change it by running [gcloud config set compute/region NAME].
Created a default .boto configuration file at [/home/<username>/.boto]. See this file and
[https://cloud.google.com/storage/docs/gsutil/commands/config] for more
information about configuring Google Cloud Storage.
Your Google Cloud SDK is configured and ready to use!
* Commands that require authentication will use <gmail account> by default
* Commands will reference project `<project-id>` by default
* Compute Engine commands will use region `us-west2` by default
* Compute Engine commands will use zone `us-west2-b` by default
Run `gcloud help config` to learn how to change individual settings
This gcloud configuration is called [default]. You can create additional configurations if you work with multiple accounts and/or projects.
Run `gcloud topic configurations` to learn more.
Some things to try next:
* Run `gcloud --help` to see the Cloud Platform services you can interact with. And run `gcloud help COMMAND` to get help on any gcloud command.
* Run `gcloud topic -h` to learn about advanced features of the SDK like arg files and output formatting1.2 GCP 资源创建
接下来创建 Kuernetes 所需的 GCP 资源．
第一步是创建网络和子网．
$ gcloud compute networks create cka --subnet-mode custom
$ gcloud compute networks subnets create kubernetes --network cka --range 10.240.0.0/24接下来要创建防火墙规则，配置哪些端口是可以开放访问的．一共两条规则，一个外网，一个内网．
外网规则只需要开放 ssh, ping 和 kube-api 的访问就足够了：
$ gcloud compute firewall-rules create cka-external --allow tcp:22,tcp:6443,icmp --network cka --source-ranges 0.0.0.0/0内网规则设置好 GCP 虚拟机网段和后面 pod 的网段可以互相访问即可，因为后面会使用 calico 作为网络插件，所以只开放 TCP, UDP 和 ICMP 是不够的，还需要开放 BGP，但 GCP 的防火墙规则中没有 BGP 选项，所以放开全部协议的互通．
$ gcloud compute firewall-rules create cka-internal --network cka --allow=all --source-ranges 192.168.0.0/16,10.240.0.0/16最后创建 GCP 虚拟机实例．
$ gcloud compute instances create controller-1 --async --boot-disk-size 200GB --can-ip-forward --image-family ubuntu-1804-lts --image-project ubuntu-os-cloud --machine-type n1-standard-1 --private-network-ip 10.240.0.11 --scopes compute-rw,storage-ro,service-management,service-control,logging-write,monitoring --subnet kubernetes --tags cka,controller
$ gcloud compute instances create worker-1 --async --boot-disk-size 200GB --can-ip-forward --image-family ubuntu-1804-lts --image-project ubuntu-os-cloud --machine-type n1-standard-1 --private-network-ip 10.240.0.21 --scopes compute-rw,storage-ro,service-management,service-control,logging-write,monitoring --subnet kubernetes --tags cka,worker2. 主节点配置
使用 gcloud 登录 controller-1
$ gcloud compute ssh controller-1
WARNING: The public SSH key file for gcloud does not exist.
WARNING: The private SSH key file for gcloud does not exist.
WARNING: You do not have an SSH key for gcloud.
WARNING: SSH keygen will be executed to generate a key.
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/<username>/.ssh/google_compute_engine.
Your public key has been saved in /home/<username>/.ssh/google_compute_engine.pub.
The key fingerprint is:
SHA256:jpaZtzz42t7FjB1JV06GeVHhXVi12LF/a+lfl7TK2pw <username>@<username>
The key's randomart image is:
+---[RSA 2048]----+
| O&|
| B=B|
| ...*o|
| . o .|
| S o .o|
| * = .. *|
| *.o . = *o|
| ..+.o .+ = o|
| .+*....E .o|
+----[SHA256]-----+
Updating project ssh metadata...⠧Updated [https://www.googleapis.com/compute/v1/projects/<project-id>].
Updating project ssh metadata...done.
Waiting for SSH key to propagate.
Warning: Permanently added 'compute.2329485573714771968' (ECDSA) to the list of known hosts.
Welcome to Ubuntu 18.04.1 LTS (GNU/Linux 4.15.0-1025-gcp x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
System information as of Wed Dec 5 03:05:31 UTC 2018
System load: 0.0 Processes: 87
Usage of /: 1.2% of 96.75GB Users logged in: 0
Memory usage: 5% IP address for ens4: 10.240.0.11
Swap usage: 0%
Get cloud support with Ubuntu Advantage Cloud Guest:
http://www.ubuntu.com/business/services/cloud
0 packages can be updated.
0 updates are security updates.
$ ssh -l<user-name> -i .ssh/google_compute_engine.pub 35.236.126.174安装 kubeadm, docker, kubelet, kubectl．
$ sudo apt update
$ sudo apt upgrade -y
$ sudo apt-get install -y docker.io$ sudo vim /etc/apt/sources.list.d/kubernetes.list
deb http://apt.kubernetes.io/ kubernetes-xenial main$ curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
OK$ sudo apt update
$ sudo apt-get install -y \
kubeadm=1.12.2-00 kubelet=1.12.2-00 kubectl=1.12.2-00kubeadm 初始化
$ sudo kubeadm init --pod-network-cidr 192.168.0.0/16配置 calico 网络插件
$ wget https://tinyurl.com/yb4xturm \
-O rbac-kdd.yaml
$ wget https://tinyurl.com/y8lvqc9g \
-O calico.yaml
$ kubectl apply -f rbac-kdd.yaml
$ kubectl apply -f calico.yaml配置 kubectl 的 bash 自动补全．
$ source <(kubectl completion bash)
$ echo "source <(kubectl completion bash)" >> ~/.bashrc3. 从节点配置
这里偷懒了一下，从节点安装的包和主节点一模一样，大家可以根据需求，去掉一些不必要的包．
$ sudo apt-get update && sudo apt-get upgrade -y
$ apt-get install -y docker.io$ sudo vim /etc/apt/sources.list.d/kubernetes.list
deb http://apt.kubernetes.io/ kubernetes-xenial main$ curl -s \
https://packages.cloud.google.com/apt/doc/apt-key.gpg \
| sudo apt-key add -
$ sudo apt-get update
$ sudo apt-get install -y \
kubeadm=1.12.2-00 kubelet=1.12.2-00 kubectl=1.12.2-00如果此时 kubeadm init 命令中的 join 命令找不到了，或者 bootstrap token 过期了，该怎么办呢，下面就是解决方法．
$ sudo kubeadm token list
TOKEN TTL EXPIRES USAGES DESCRIPTION
27eee4.6e66ff60318da929 23h 2017-11-03T13:27:33Z
authentication,signing The default bootstrap token generated
by ’kubeadm init’....
$ sudo kubeadm token create
27eee4.6e66ff60318da929
$ openssl x509 -pubkey \
-in /etc/kubernetes/pki/ca.crt | openssl rsa \
-pubin -outform der 2>/dev/null | openssl dgst \
-sha256 -hex | sed ’s/^.* //’
6d541678b05652e1fa5d43908e75e67376e994c3483d6683f2a18673e5d2a1b0最后执行 kubeadm join 命令．
$ sudo kubeadm join \
--token 27eee4.6e66ff60318da929 \
10.128.0.3:6443 \
--discovery-token-ca-cert-hash \
sha256:6d541678b05652e1fa5d43908e75e67376e994c3483d6683f2a18673e5d2a1b0