k8s 安装 istio 的坑

本文针对于二进制部署的k8s安装istio1.67版本

没有设置admin.conf的小伙伴请参考

https://www.cnblogs.com/Tempted/p/13469772.html

1、检查k8s dns svc 启动是否正常

istio pod 访问不到svc错误，请检查K8S 上dns服务是否正常

error   citadelclient   Failed to create certificate: rpc error: code = Unavailable desc = connection error: desc = "transport: Error while dialing dial tcp: lookup istiod.istio-system.svc on 10.254.0.2:53: read udp 172.30.1.57:52724->10.254.0.2:53: i/o timeout"

2、master 上需要部署一个node节点，并设置为不可调度

1,不可调度

kubectl cordon master
kubectl uncordon master       #取消

2,驱逐已经运行的业务容器
kubectl drain --ignore-daemonsets --delete-local-data  master

3，如果想删除node 节点，则进行这个步骤
kubectl delete node master

istio自动注入错误

Error creating: Internal error occurred: failed calling webhook "sidecar-injector.istio.io": Post https://istio-sidecar-injector.istio-system.svc:443/inject?timeout=30s: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

此错误是因为master节点访问不了集群内部的Service（istio-sidecar-injector)，导致自动注入失败。　

安装istio

一、下载

官方地址：

https://preliminary.istio.io/latest/zh/docs/setup/getting-started/

github 下载地址

https://github.com/istio/istio/releases/

二、配置

[root@master ~]#  tar -zxf istio-1.6.7-linux-amd64.tar.gz

[root@master ~]#  cd istio-1.6.7

添加istioctl 环境变量
[root@master ~]#  vi ~/.bash_profile
# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
        . ~/.bashrc
fi

# User specific environment and startup programs

PATH=$PATH:$HOME/bin
PATH=$PATH:/root/istio-1.6.7/bin

export PATH

[root@master ~]#  source ~/.bash_profile

添加istio自动补全工具
[root@master ~]# cp  tools/istioctl.bash ~/.istioctl.bash

[root@master ~]# source  ~/.istioctl.bash

c-bash: _get_comp_words_by_ref: command not found 碰到这样的错误解决方法：

yum install bash-completion -y

source /usr/share/bash-completion/bash_completion

source ~/.istioctl.bash

k8s 自动补全

source <(kubectl completion bash)
echo "source <(kubectl completion bash)" >> ~/.bashrc

#添加kubectl的k别名
vim   ~/.bashrc 
alias k='kubectl'
  
#tab命令只在使用完整的kubectl 命令起作用，使用别名k 时不起作用，修补：
 source <( kubectl completion bash | sed 's/kubectl/k/g' )  #写入 .bashrc

三、安装

以官方为主：https://preliminary.istio.io/latest/zh/docs/setup/getting-started/

　1、安装demo配置

　　istioctl manifest apply --set profile=demo

2、添加自动注入

kubectl create ns name

kubectl label namespace <namespace> istio-injection=enabled

kubectl apply -n <namespace> -f <your-app-spec>.yaml

一个自动注入yaml demo

apiVersion: apps/v1
kind: Deployment
metadata:
  name: demo
  labels:
    app: demo
spec:
  replicas: 1
  selector:
    matchLabels:
      app: demo
  template:
    metadata:
      labels:
        app: demo
    spec:
      containers:
      - name: nginx
        image: nginx:1.14-alpine
        imagePullPolicy: IfNotPresent
        ports:
        - containerPort: 80

3、卸载

　　istioctl manifest generate --set profile=demo | kubectl delete -f -