在pod上直接使用Pod存储卷分为两步

  1. 在pod的Volumes字段上定义存储卷名称及存储卷
  2. 在容器内部挂载Volumes字段中所定义的存储卷。

emptyDir类型

emptyDir类型的存储卷不可持久存储，其生命周期和容器生命周期相同。

emptyDir示例

1.创建配置清单

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
root@k8s-master01:~/yaml/chapter05# vim volumes-empyterdir-demo.yaml
apiVersion: v1
kind: Pod
metadata:
  name: volumes-emptydir-demo
  namespace: default
spec:
  initContainers:
  - name: config-file-downloader
    image: ikubernetes/admin-box
    imagePullPolicy: IfNotPresent
    command: ["/bin/sh","-c","wget -O /data/envoy.yaml http://ilinux.io/envoy.yaml"]
    volumeMounts:
    - name: config-file-store
      mountPath: /data
  containers:
  - name: envoy
    image: envoyproxy/envoy-alpine:v1.13.1
    command: ['/bin/sh','-c']
    args: ['envoy -c /etc/envoy/envoy.yaml']
    volumeMounts:												# 挂载存储卷
    - name: config-file-store
      mountPath: /etc/envoy
      readOnly: true
  volumes:															# 定义存储卷
  - name: config-file-store							# 存储卷名称
    emptyDir:														# 存储卷类型
      medium: Memory                    # 存储介质，默认磁盘
      sizeLimit: 16Mi

2.应用配置清单

1
2
root@k8s-master01:~/yaml/chapter05# kubectl apply -f volumes-empyterdir-demo.yaml 
pod/volumes-emptydir-demo created

3.查看容器内的挂载点

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
# 查看容器内的配置文件是否被成功挂载
root@k8s-master01:~/yaml/chapter05# kubectl exec volumes-emptydir-demo -- cat /etc/envoy/envoy.yaml
Defaulted container "envoy" out of: envoy, config-file-downloader (init)
admin:
  access_log_path: /tmp/admin_access.log
  address:
    socket_address: { address: 0.0.0.0, port_value: 9901 }

static_resources:
  listeners:
  - name: listener_0
    address:
      socket_address: { address: 0.0.0.0, port_value: 80 }
    filter_chains:
    - filters:
      - name: envoy.http_connection_manager
        config:
          stat_prefix: ingress_http
          codec_type: AUTO
          route_config:
            name: local_route
            virtual_hosts:
            - name: local_service
              domains: ["*"]
              routes:
              - match: { prefix: "/" }
                route: { cluster: local_service }
          http_filters:
          - name: envoy.router

  clusters:
  - name: local_service
    connect_timeout: 0.25s
    type: STATIC
    lb_policy: ROUND_ROBIN
    load_assignment:
      cluster_name: local_service
      endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: 127.0.0.1
                port_value: 8080
                
# 查看容器内的监听端口
root@k8s-master01:~/yaml/chapter05# kubectl exec volumes-emptydir-demo -- netstat -tnl
Defaulted container "envoy" out of: envoy, config-file-downloader (init)
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      
tcp        0      0 0.0.0.0:9901            0.0.0.0:*               LISTEN      

# 查看卷挂载
root@k8s-master01:~/yaml/chapter05# kubectl exec volumes-emptydir-demo -- mount | grep envoy
Defaulted container "envoy" out of: envoy, config-file-downloader (init)
tmpfs on /etc/envoy type tmpfs (ro,relatime)

# 卷挂载成功。

hostPath类型

hostPath类型的挂在卷，是将本地的某个存在的路径挂载到容器内部指定的挂载目录下。

hostPath的挂在卷可以指定其类型，其具体的挂载类型有以下几种：

  • File：事先必须存在的文件路径；
  • Directory：事先必须存在的目录路径；
  • DirectoryOrCreate：指定的路径不存时自动将其创建为0755权限的空目录，属主属组均为kubelet；
  • FileOrCreate：指定的路径不存时自动将其创建为0644权限的空文件，属主和属组同为kubelet；
  • Socket：事先必须存在的Socket文件路径；
  • CharDevice：事先必须存在的字符设备文件路径；
  • BlockDevice：事先必须存在的块设备文件路径；
  • “”：空字符串，默认配置，在关联hostPath存储卷之前不进行任何检查。

hostPath示例

1.编写配置清单

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
root@k8s-master01:~/yaml/chapter05# vim volumes-hostpath-demo.yaml
apiVersion: v1
kind: Pod
metadata:
  name: volumes-hostpath-demo
spec:
  containers:
  - name: filebeat
    image: ikubernetes/filebeat:5.6.7-alpine
    env:
    - name: REDIS_HOST
      value: redis.ilinux.io:6379
    - name: LOG_LEVEL
      value: info
    volumeMounts:
    - name: varlog
      mountPath: /var/log
    - name: socket
      mountPath: /var/run/docker.sock
    - name: varlibdockercontainers
      mountPath: /var/lib/docker/contianers
      readOnly: true
  volumes:
  - name: varlog
    hostPath:
      path: /var/log
  - name: varlibdockercontainers
    hostPath:
      path: /var/lib/docker/containers
  - name: socket
    hostPath:
      path: /var/run/docker.sock

2.应用配置清单

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
root@k8s-master01:~/yaml/chapter05# kubectl apply -f volumes-hostpath-demo.yaml 
pod/volumes-hostpath-demo created

# 查看pod详细信息
root@k8s-master01:~/yaml/chapter05# kubectl describe pods volumes-hostpath-demo 
Name:         volumes-hostpath-demo
Namespace:    default
Priority:     0
Node:         k8s-node03/172.16.11.83
Start Time:   Tue, 13 Jul 2021 06:28:13 +0000
Labels:       <none>
Annotations:  <none>
Status:       Running
IP:           10.244.3.79
IPs:
  IP:  10.244.3.79
Containers:
  filebeat:
    Container ID:   docker://46a9666f684bb0ac85c71d36c276546ab48b8195efb34ac061bdb26f09468a1a
    Image:          ikubernetes/filebeat:5.6.7-alpine
    Image ID:       docker-pullable://ikubernetes/filebeat@sha256:3957f67b612aa8628f643f8ede02b71bfbabf34892ef136f1e5ee18bbc0775aa
    Port:           <none>
    Host Port:      <none>
    State:          Running
      Started:      Tue, 13 Jul 2021 06:28:24 +0000
    Ready:          True
    Restart Count:  0
    Environment:
      REDIS_HOST:  redis.ilinux.io:6379
      LOG_LEVEL:   info
    Mounts:																																			# 容器的挂载卷信息
      /var/lib/docker/contianers from varlibdockercontainers (ro)
      /var/log from varlog (rw)
      /var/run/docker.sock from socket (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-wqhfx (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             True 
  ContainersReady   True 
  PodScheduled      True 
Volumes:
  varlog:
    Type:          HostPath (bare host directory volume)
    Path:          /var/log
    HostPathType:  
  varlibdockercontainers:
    Type:          HostPath (bare host directory volume)
    Path:          /var/lib/docker/containers
    HostPathType:  
  socket:
    Type:          HostPath (bare host directory volume)
    Path:          /var/run/docker.sock
    HostPathType:  
  kube-api-access-wqhfx:
    Type:                    Projected (a volume that contains injected data from multiple sources)
    TokenExpirationSeconds:  3607
    ConfigMapName:           kube-root-ca.crt
    ConfigMapOptional:       <nil>
    DownwardAPI:             true
QoS Class:                   BestEffort
Node-Selectors:              <none>
Tolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                             node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type    Reason     Age   From               Message
  ----    ------     ----  ----               -------
  Normal  Scheduled  55s   default-scheduler  Successfully assigned default/volumes-hostpath-demo to k8s-node03
  Normal  Pulling    53s   kubelet            Pulling image "ikubernetes/filebeat:5.6.7-alpine"
  Normal  Pulled     45s   kubelet            Successfully pulled image "ikubernetes/filebeat:5.6.7-alpine" in 8.108131139s
  Normal  Created    44s   kubelet            Created container filebeat
  Normal  Started    44s   kubelet            Started container filebeat          # 容器已经启动

NFS类型存储卷

NFS为网络类型的存储卷，其要确保每个k8s的节点上必须能够挂载nfs文件系统。

NFS示例

1.配置一台nfs-server

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
# 查看nfs服务器地址
[root@nfs ~]# ip a show eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:f5:86:46 brd ff:ff:ff:ff:ff:ff
    inet 172.16.11.79/24 brd 172.16.11.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::128c:e1f8:720f:875f/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
       
# 创建共享目录
[root@nfs ~]# mkdir -pv /data/redis
mkdir: created directory '/data'
mkdir: created directory '/data/redis'

# 让999用户对/data/redis目录有读写权限
[root@nfs ~]# chown 999 /data/redis
[root@nfs ~]# ls -ld /data/redis
drwxr-xr-x 2 systemd-coredump root 4096 Jul 13 14:47 /data/redis
[root@nfs ~]# id systemd-coredump
uid=999(systemd-coredump) gid=997(systemd-coredump) groups=997(systemd-coredump)

# 配置nfs
[root@nfs ~]# vim /etc/exports 
/data/redis   172.16.11.0/24(rw)

# 安装nfs-utils
[root@nfs ~]# dnf install nfs-utils -y

# 启动nfs
[root@nfs ~]# systemctl start nfs-server.service 

# 查看2049端口是否被监听
[root@nfs ~]# ss -tnl | grep 2049
LISTEN 0      64           0.0.0.0:2049       0.0.0.0:*          
LISTEN 0      64              [::]:2049          [::]:*

2.在所有k8s节点上安装nfs驱动

1
2
3
4
5
6
7
8
root@k8s-node01:~# apt install nfs-common

# 测试手动挂载
root@k8s-node02:~# mount -t nfs 172.16.11.79:/data/redis /mnt

# 查看是否被挂载
root@k8s-node02:~# mount | grep mnt
172.16.11.79:/data/redis on /mnt type nfs4 (rw,relatime,vers=4.2,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=172.16.11.82,local_lock=none,addr=172.16.11.79)

3.编辑配置清单

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
root@k8s-master01:~/yaml/chapter05# vim volumes-nfs-demo.yaml
apiVersion: v1
kind: Pod
metadata:
  name: volumes-nfs-demo
  labels:
    app: redis
spec:
  containers:
  - name: redis
    image: redis:alpine
    ports:
    - containerPort: 6379
      name: redisport
    securityContext:
      runAsUser: 999            # 此处使用的用户为id是999的用户，要确保nfs服务器上id 999的用户对挂载的目录有写权限。
    volumeMounts:
    - mountPath: /data
      name: redisdata
  volumes:
  - name: redisdata
    nfs:
      server: 172.16.11.79
      path: /data/redis
      readOnly: false

4.应用配置清单

1
2
root@k8s-master01:~/yaml/chapter05# kubectl apply -f volumes-nfs-demo.yaml 
pod/volumes-nfs-demo created

5.查看pod详细信息

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
root@k8s-master01:~/yaml/chapter05# kubectl describe pod volumes-nfs-demo 
Name:         volumes-nfs-demo
Namespace:    default
Priority:     0
Node:         k8s-node01/172.16.11.81
Start Time:   Tue, 13 Jul 2021 07:22:24 +0000
Labels:       app=redis
Annotations:  <none>
Status:       Running
IP:           10.244.1.50
IPs:
  IP:  10.244.1.50
Containers:
  redis:
    Container ID:   docker://d06c8e430cb3b38c9e266ee50b1caeaf834f4b51b6270540735eff780bc2f968
    Image:          redis:alpine
    Image ID:       docker-pullable://redis@sha256:442fbfdeccf203c277827cfd8e7e727ce411611e1a6caeda9cca8115ed17b9cc
    Port:           6379/TCP
    Host Port:      0/TCP
    State:          Running
      Started:      Tue, 13 Jul 2021 07:22:40 +0000
    Ready:          True
    Restart Count:  0
    Environment:    <none>
    Mounts:
      /data from redisdata (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-wppkn (ro)
Conditions:
  Type              Status
  Initialized       True 
  Ready             True 
  ContainersReady   True 
  PodScheduled      True 
Volumes:
  redisdata:
    Type:      NFS (an NFS mount that lasts the lifetime of a pod)
    Server:    172.16.11.79
    Path:      /data/redis
    ReadOnly:  false
  kube-api-access-wppkn:
    Type:                    Projected (a volume that contains injected data from multiple sources)
    TokenExpirationSeconds:  3607
    ConfigMapName:           kube-root-ca.crt
    ConfigMapOptional:       <nil>
    DownwardAPI:             true
QoS Class:                   BestEffort
Node-Selectors:              <none>
Tolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                             node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type    Reason     Age   From               Message
  ----    ------     ----  ----               -------
  Normal  Scheduled  87s   default-scheduler  Successfully assigned default/volumes-nfs-demo to k8s-node01
  Normal  Pulling    86s   kubelet            Pulling image "redis:alpine"
  Normal  Pulled     74s   kubelet            Successfully pulled image "redis:alpine" in 11.045849701s
  Normal  Created    73s   kubelet            Created container redis
  Normal  Started    72s   kubelet            Started container redis