1. k8s-pod常用管理命令

創(chuàng)建Pod：

kubectl apply -f pod.yaml
kubectl run nginx --image=nginx

查看Pod：

kubectl get pods
kubectl describe pod 

查看日志：

kubectl logs  [-c CONTAINER]
kubectl logs  [-c CONTAINER] -f

進(jìn)入容器終端：

kubectl exec  [-c CONTAINER] --bash

刪除Pod：

kubectl delete 

導(dǎo)出pod的yaml配置文件

[root@k8s-master yaml]# kubectl get pods 
NAME                     READY   STATUS    RESTARTS   AGE
nginx-6799fc88d8-s5wvx   1/1     Running   1          40h
test-5f655598-5jfrt      1/1     Running   1          20h
test-5f655598-bhhm4      1/1     Running   1          20h
test-5f655598-v5l8f      1/1     Running   1          20h
web-674477549d-flj78     1/1     Running   1          39h
web-674477549d-m7lsj     1/1     Running   1          23h
web-674477549d-stk84     1/1     Running   1          23h
[root@k8s-master yaml]# kubectl get pods web-674477549d-flj78 -o yaml >web-pod.yaml

2. k8s-pod案例

2.1 實(shí)現(xiàn)網(wǎng)絡(luò)共享

2.1.1 導(dǎo)出配置文件，進(jìn)行編寫案例

編寫導(dǎo)出的web-pod.yaml文件進(jìn)行測試

[root@k8s-master yaml]# kubectl get pods 
NAME                     READY   STATUS    RESTARTS   AGE
nginx-6799fc88d8-s5wvx   1/1     Running   1          40h
test-5f655598-5jfrt      1/1     Running   1          20h
test-5f655598-bhhm4      1/1     Running   1          20h
test-5f655598-v5l8f      1/1     Running   1          20h
web-674477549d-flj78     1/1     Running   1          39h
web-674477549d-m7lsj     1/1     Running   1          23h
web-674477549d-stk84     1/1     Running   1          23h
[root@k8s-master yaml]# kubectl get pods web-674477549d-flj78 -o yaml >web-pod.yaml 
[root@k8s-master yaml]# vim web-pod.yaml 
[root@k8s-master yaml]# cat web-pod.yaml 
apiVersion: v1
kind: Pod
metadata:
  labels:
    app: pod-test
  name: pod-net-test
  namespace: default
spec:
  containers:
  - image: busybox
    imagePullPolicy: Always
    name: pod-test
    command: ["/bin/sh"]
    args: 
      - "-c"
      - "sleep 3000000"
      
  - image: nginx
    name: web

2.1.2 啟動(dòng)配置文件

[root@k8s-master yaml]# kubectl apply  -f web-pod.yaml 
pod/pod-net-test created

2.1.3 監(jiān)控pod是否啟動(dòng)

[root@k8s-master yaml]# kubectl get pods
NAME                     READY   STATUS              RESTARTS   AGE
nginx-6799fc88d8-s5wvx   1/1     Running             1          41h
pod-net-test             0/2     ContainerCreating   0          19s
test-5f655598-5jfrt      1/1     Running             1          21h
test-5f655598-bhhm4      1/1     Running             1          21h
test-5f655598-v5l8f      1/1     Running             1          21h
web-674477549d-flj78     1/1     Running             1          40h
web-674477549d-m7lsj     1/1     Running             1          23h
web-674477549d-stk84     1/1     Running             1          23h
[root@k8s-master yaml]# kubectl get pods -w
NAME                     READY   STATUS    RESTARTS   AGE
nginx-6799fc88d8-s5wvx   1/1     Running   1          41h
pod-net-test             2/2     Running   0          89s
test-5f655598-5jfrt      1/1     Running   1          21h
test-5f655598-bhhm4      1/1     Running   1          21h
test-5f655598-v5l8f      1/1     Running   1          21h
web-674477549d-flj78     1/1     Running   1          40h
web-674477549d-m7lsj     1/1     Running   1          23h
web-674477549d-stk84     1/1     Running   1          23h

注釋：這里注意一下，可以是 “-w ” 持續(xù)監(jiān)聽pod狀態(tài)

2.1.4 進(jìn)入pod

[root@k8s-master pod]# kubectl exec -it pods/pod-net-test -c pod-test -- /bin/sh
Defaulting container name to pod-test.
Use 'kubectl describe pod/pod-net-test -n default' to see all of the containers in this pod.
/ # ifconfig 
eth0      Link encap:Ethernet  HWaddr 5AFA85:C0  
          inet addr:10.244.169.139  Bcast:10.244.169.139  Mask:255.255.255.255
          UP BROADCAST RUNNING MULTICAST  MTU:1480  Metric:1
          RX packets:5 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:446 (446.0 B)  TX bytes:0 (0.0 B)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

/ # netstat -lntup
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      -
tcp        0      0 :::80                   :::*                    LISTEN      -

注釋：

exec：進(jìn)入?yún)?shù)

-it：分配一個(gè)偽終端

pod-net-test：為容器名稱

-c pod-test：指定容器名稱pod-test

-- /bin/sh：為使用的環(huán)境變量

2.1.5 我們驗(yàn)證文件是不是nginx

我們進(jìn)入nginx的容器里面，修改index.html文件進(jìn)行驗(yàn)證

[root@k8s-master yaml]# kubectl exec -it  pod-net-test  -c web -- /bin/bash
root@pod-net-test:/# cd /usr/share/nginx/html/
root@pod-net-test:/usr/share/nginx/html# ls
50x.html  index.html
root@pod-net-test:/usr/share/nginx/html# echo 'pod-test' >index.html

退出nginx容器，進(jìn)入busybox進(jìn)行wget下載，驗(yàn)證文件是否是pod-test

[root@k8s-master yaml]# kubectl exec -it  pod-net-test  -c pod-test -- /bin/sh
/ # netstat -lntup
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      -
tcp        0      0 :::80                   :::*                    LISTEN      -
/ # wget http://127.0.0.1:80
Connecting to 127.0.0.1:80 (127.0.0.1:80)
saving to 'index.html'
index.html           100% |************************************************************************************************************************************************|     9  000 ETA
'index.html' saved
/ # cat index.html 
pod-test

小結(jié)：

我們在nginx啟動(dòng)的時(shí)候，沒有ip add等相關(guān)命令，我們通過修改index.html文件進(jìn)行驗(yàn)證

注意使用進(jìn)入命令的時(shí)候，一定要使用 “-c ” 參數(shù)區(qū)分進(jìn)入那個(gè)容器

2.2 實(shí)現(xiàn)共享存儲

2.2.1 導(dǎo)出配置文件，進(jìn)行編寫案例

進(jìn)入目錄

[root@k8s-master ~]# cd /root/yaml/
[root@k8s-master yaml]# ll
總用量 24
-rw-r--r--  1 root root  389 11月 27 21:22 my-deploy.yaml
-rw-r--r--  1 root root 3722 11月 28 10:48 my-get-deploy.yaml
-rw-r--r--. 1 root root  538 11月 27 17:00 service-test.yaml
-rw-r--r--  1 root root  792 11月 29 08:09 web-disk-pod.yaml
-rw-r--r--  1 root root  302 11月 28 13:39 web-pod.yaml
-rw-r--r--. 1 root root  777 11月 27 16:32 yaml-test.yaml

編寫pod-volume-test.yaml配置文件

[root@k8s-master yaml]# vim pod-volume-test.yaml 
[root@k8s-master yaml]# cat pod-volume-test.yaml 
apiVersion: v1
kind: Pod
metadata:
  labels:
    app: test
  name: pod-volume-test
  namespace: default
spec:
  containers:
  - image: busybox
    imagePullPolicy: Always
    name: test
    command: ["/bin/sh"]
    args: 
      - "-c"
      - "sleep 3000000"

    volumeMounts:      #掛載到容器內(nèi)部的存儲卷配置  
    - name: log       # 引用pod定義的共享存儲卷的名稱
      mountPath: /data               #共享路徑文件夾

      
  - image: nginx
    name: web
    volumeMounts:      #掛載到容器內(nèi)部的存儲卷配置  
    - name: log       # 引用pod定義的共享存儲卷的名稱
      mountPath: /data               #共享路徑文件夾


  #建立共享存儲卷
  volumes:
  - name: log           #共享存儲卷名稱
    emptyDir: {}

2.2.2 創(chuàng)建共享磁盤

[root@k8s-master yaml]# mkdir -p /data

2.2.3 啟動(dòng)服務(wù)

[root@k8s-master yaml]# kubectl apply -f pod-volume-test.yaml 
pod/pod-volume-test created

2.2.4 查看服務(wù)是否啟動(dòng)

[root@k8s-master yaml]# kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-6799fc88d8-tfgfr   1/1     Running   0          30m
pod-volume-test          2/2     Running   0          2m37s
test-5f655598-j9rth      1/1     Running   0          30m
test-5f655598-kpp8k      1/1     Running   0          30m
test-5f655598-t6mfg      1/1     Running   0          30m
web-674477549d-7gqfr     1/1     Running   0          30m
web-674477549d-cttbc     1/1     Running   0          30m
web-674477549d-rrfqd     1/1     Running   0          30m

2.2.5 驗(yàn)證數(shù)據(jù)卷是否被共享

進(jìn)入pod容器，在web容器創(chuàng)建一個(gè)index.html，文件內(nèi)容為 "pod volume test"

[root@k8s-master yaml]# kubectl exec -it pod-volume-test -c web -- /bin/bash
root@pod-volume-test:/# cd /data/
root@pod-volume-test:/data# touch index.html
root@pod-volume-test:/data# echo 'pod volume test ' >index.html 
root@pod-volume-test:/data# ls
index.html

進(jìn)入容器test進(jìn)行驗(yàn)證，/data目錄下面是否有index.html文件，內(nèi)容是否 “pod volume test”

[root@k8s-master yaml]# kubectl exec -it pod-volume-test -c test -- /bin/sh
/ # cd /data/
/data # ls
index.html
/data # cat index.html 
pod volume test

2.2.6 查看日志

查看web日志

[root@k8s-master ~]# kubectl get pods
NAME                     READY   STATUS    RESTARTS   AGE
nginx-6799fc88d8-tfgfr   1/1     Running   0          54m
pod-volume-test          2/2     Running   0          26m
test-5f655598-j9rth      1/1     Running   0          54m
test-5f655598-kpp8k      1/1     Running   0          54m
test-5f655598-t6mfg      1/1     Running   0          54m
web-674477549d-7gqfr     1/1     Running   0          54m
web-674477549d-cttbc     1/1     Running   0          54m
web-674477549d-rrfqd     1/1     Running   0          54m
[root@k8s-master ~]# kubectl logs pod-volume-test -c web -f 
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Configuration complete; ready for start up

上面開啟監(jiān)聽日志，

進(jìn)入test測試終端，進(jìn)行訪問測試

[root@k8s-master yaml]# kubectl exec -it pod-volume-test -c test -- /bin/sh
/data # cd /tmp/
/tmp # wget http://127.0.0.1
Connecting to 127.0.0.1 (127.0.0.1:80)
saving to 'index.html'
index.html           100% |******************************************************************************************************************************************************************************************************************************|   612  000 ETA
'index.html' saved
/tmp # cat index.html 







Welcome to nginx!
If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.

For online documentation and support please refer to
nginx.org.

Commercial support is available at
nginx.com.

Thank you for using nginx.

查看監(jiān)控日志情況

[root@k8s-master ~]# kubectl logs pod-volume-test -c web -f 
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Configuration complete; ready for start up


127.0.0.1 - - [29/Nov/202051:12 +0000] "GET / HTTP/1.1" 200 612 "-" "Wget" "-"

發(fā)現(xiàn)已經(jīng)有日志了

3. k8s-pod字段詳解

# yaml格式的pod定義文件完整內(nèi)容：
apiVersion: v1#必選，版本號，例如v1
kind: Pod#必選，Pod
metadata:#必選，元數(shù)據(jù)
name: string#必選，Pod名稱
namespace: string#必選，Pod所屬的命名空間
labels:#自定義標(biāo)簽
- name: string#自定義標(biāo)簽名字
annotations:#自定義注釋列表
- name: string
spec:#必選，Pod中容器的詳細(xì)定義
containers:#必選，Pod中容器列表
- name: string#必選，容器名稱
image: string#必選，容器的鏡像名稱
imagePullPolicy: [Always | Never | IfNotPresent]#獲取鏡像的策略 Alawys表示下載鏡像 IfnotPresent表示優(yōu)先使用本地鏡像，否則下載鏡像，Nerver表示僅使用本地鏡像
command: [string]#容器的啟動(dòng)命令列表，如不指定，使用打包時(shí)使用的啟動(dòng)命令
args: [string]#容器的啟動(dòng)命令參數(shù)列表
workingDir: string#容器的工作目錄
volumeMounts:#掛載到容器內(nèi)部的存儲卷配置
- name: string#引用pod定義的共享存儲卷的名稱，需用volumes[]部分定義的的卷名
mountPath: string#存儲卷在容器內(nèi)mount的絕對路徑，應(yīng)少于512字符
readOnly: boolean#是否為只讀模式
ports:#需要暴露的端口庫號列表
- name: string#端口號名稱
containerPort: int#容器需要監(jiān)聽的端口號
hostPort: int#容器所在主機(jī)需要監(jiān)聽的端口號，默認(rèn)與Container相同
protocol: string#端口協(xié)議，支持TCP和UDP，默認(rèn)TCP
env:#容器運(yùn)行前需設(shè)置的環(huán)境變量列表
- name: string#環(huán)境變量名稱
value: string#環(huán)境變量的值
resources:#資源限制和請求的設(shè)置
limits:#資源限制的設(shè)置
cpu: string#Cpu的限制，單位為core數(shù)，將用于docker run --cpu-shares參數(shù)
memory: string#內(nèi)存限制，單位可以為Mib/Gib，將用于docker run --memory參數(shù)
requests:#資源請求的設(shè)置
cpu: string#Cpu請求，容器啟動(dòng)的初始可用數(shù)量
memory: string#內(nèi)存清楚，容器啟動(dòng)的初始可用數(shù)量
livenessProbe:#對Pod內(nèi)個(gè)容器健康檢查的設(shè)置，當(dāng)探測無響應(yīng)幾次后將自動(dòng)重啟該容器，檢查方法有exec、httpGet和tcpSocket，對一個(gè)容器只需設(shè)置其中一種方法即可
exec:#對Pod容器內(nèi)檢查方式設(shè)置為exec方式
command: [string]#exec方式需要制定的命令或腳本
httpGet:#對Pod內(nèi)個(gè)容器健康檢查方法設(shè)置為HttpGet，需要制定Path、port
path: string
port: number
host: string
scheme: string
HttpHeaders:
- name: string
value: string
tcpSocket:#對Pod內(nèi)個(gè)容器健康檢查方式設(shè)置為tcpSocket方式
port: number
initialDelaySeconds: 0#容器啟動(dòng)完成后首次探測的時(shí)間，單位為秒
timeoutSeconds: 0#對容器健康檢查探測等待響應(yīng)的超時(shí)時(shí)間，單位秒，默認(rèn)1秒
periodSeconds: 0#對容器監(jiān)控檢查的定期探測時(shí)間設(shè)置，單位秒，默認(rèn)10秒一次
successThreshold: 0
failureThreshold: 0
securityContext:
privileged:false
restartPolicy: [Always | Never | OnFailure]#Pod的重啟策略，Always表示一旦不管以何種方式終止運(yùn)行，kubelet都將重啟，OnFailure表示只有Pod以非0退出碼退出才重啟，Nerver表示不再重啟該P(yáng)od
    nodeSelector: obeject#設(shè)置NodeSelector表示將該P(yáng)od調(diào)度到包含這個(gè)label的node上，以key：value的格式指定
imagePullSecrets:#Pull鏡像時(shí)使用的secret名稱，以key：secretkey格式指定
- name: string
hostNetwork:false#是否使用主機(jī)網(wǎng)絡(luò)模式，默認(rèn)為false，如果設(shè)置為true，表示使用宿主機(jī)網(wǎng)絡(luò)
volumes:#在該pod上定義共享存儲卷列表
- name: string#共享存儲卷名稱 （volumes類型有很多種）
emptyDir: {}#類型為emtyDir的存儲卷，與Pod同生命周期的一個(gè)臨時(shí)目錄。為空值
hostPath: string#類型為hostPath的存儲卷，表示掛載Pod所在宿主機(jī)的目錄
path: string#Pod所在宿主機(jī)的目錄，將被用于同期中mount的目錄
secret:#類型為secret的存儲卷，掛載集群與定義的secre對象到容器內(nèi)部
scretname: string
items:
- key: string
path: string
configMap:#類型為configMap的存儲卷，掛載預(yù)定義的configMap對象到容器內(nèi)部
name: string
items:
- key: string

path: string

鏈接：https://www.cnblogs.com/scajy/p/15475993.html