数据持久化需要数据卷。kubernetes生态提供海量的存储驱动和存储使用方式。

[root@master song]# cat pod-demo.yml apiVersion: v1kind: Podmetadata:   name: pod-demo  namespace: default  labels:    app: myapp    tier: frontend    2sdlfj: dashazispec:  containers:  - name: centos    image: busybox    command: ["/bin/sh","-c","ping www.baidu.com"]    volumeMounts:    - name: song      mountPath: /data  - name: myapp-1    image: hub.c.163.com/library/nginx:1.13    volumeMounts:    - name: song      mountPath: /data  nodeSelector:    location: slave1  volumes:  - name: song    emptyDir: {} 查看状态

[root@master song]# kubectl describe pod pod-demo

Name: pod-demo

Namespace: default

Priority: 0

PriorityClassName: <none>

Node: k8s-node1/172.20.0.76

Start Time: Sun, 03 Mar 2019 09:41:53 +0800

Labels: 2sdlfj=dashazi

app=myapp

tier=frontend

Annotations: kubectl.kubernetes.io/last-applied-configuration:

{"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{},"labels":{"2sdlfj":"dashazi","app":"myapp","tier":"frontend"},"name":"pod-dem...

Status: Running

IP: 10.244.2.183

Containers:

centos:

Container ID: docker://4bc862140523df128ab1c35375459f5a08cbab3bbeb787b35ae607016bb18071

Image: busybox

Image ID: docker-pullable://busybox@sha256:061ca9704a714ee3e8b80523ec720c64f6209ad3f97c0ff7cb9ec7d19f15149f

Port: <none>

Host Port: <none>

Command:

/bin/sh

-c

ping www.baidu.com

State: Running

Started: Sun, 03 Mar 2019 09:42:01 +0800

Ready: True

Restart Count: 0

Environment: <none>

Mounts:

/data from song (rw)

/var/run/secrets/kubernetes.io/serviceaccount from default-token-tlx48 (ro)

myapp-1:

Container ID: docker://b32921dc906b58bfdf146e9a094748d7af80d21e24b58c17f6ffdc08fdee1752

Image: hub.c.163.com/library/nginx:1.13

Image ID: docker-pullable://hub.c.163.com/library/nginx@sha256:ff094de32a0d3b5efc29cec60daa709c5378cf4e53e4c9fd1d3433b87ac8ec8b

Port: <none>

Host Port: <none>

State: Running

Started: Sun, 03 Mar 2019 09:42:01 +0800

Ready: True

Restart Count: 0

Environment: <none>

Mounts:

/data from song (rw)

/var/run/secrets/kubernetes.io/serviceaccount from default-token-tlx48 (ro)

Conditions:

Type Status

Initialized True

Ready True

ContainersReady True

PodScheduled True

Volumes:

song:

Type: EmptyDir (a temporary directory that shares a pod's lifetime)  说明该类型为临时文件，不会存盘。

Medium:

default-token-tlx48:

Type: Secret (a volume populated by a Secret)

SecretName: default-token-tlx48

Optional: false

QoS Class: BestEffort

Node-Selectors: location=slave1

Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s

node.kubernetes.io/unreachable:NoExecute for 300s

Events:

Type Reason Age From Message

---- ------ ---- ---- -------

Normal Pulling 7h9m kubelet, k8s-node1 pulling image "busybox"

Normal Pulled 7h9m kubelet, k8s-node1 Successfully pulled image "busybox"

Normal Created 7h9m kubelet, k8s-node1 Created container

Normal Started 7h9m kubelet, k8s-node1 Started container

Normal Pulled 7h9m kubelet, k8s-node1 Container image "hub.c.163.com/library/nginx:1.13" already present on machine

Normal Created 7h9m kubelet, k8s-node1 Created container

Normal Started 7h9m kubelet, k8s-node1 Started container

Normal Scheduled 71s default-scheduler Successfully assigned default/pod-demo to k8s-node1

[root@master song]# kubectl exec -i -t pod-demo -c centos -- /bin/sh

/ # cd /data

/data # cat /proc/mounts

rootfs / rootfs rw 0 0

overlay / overlay rw,relatime,lowerdir=/var/lib/docker/overlay2/l/XHB5NUDL4LLGOC3EZHZJ6C2U2R:/var/lib/docker/overlay2/l/Q2CWFPROIF2I4BB6RJY5CAM74J,upperdir=/var/lib/docker/overlay2/bae727cbe291547d5703c4d488afee8b1394e2abd8bb9a271ac73bfff2468365/diff,workdir=/var/lib/docker/overlay2/bae727cbe291547d5703c4d488afee8b1394e2abd8bb9a271ac73bfff2468365/work 0 0

proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0

tmpfs /dev tmpfs rw,nosuid,size=65536k,mode=755 0 0

devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=666 0 0

sysfs /sys sysfs ro,nosuid,nodev,noexec,relatime 0 0

tmpfs /sys/fs/cgroup tmpfs ro,nosuid,nodev,noexec,relatime,mode=755 0 0

cgroup /sys/fs/cgroup/systemd cgroup ro,nosuid,nodev,noexec,relatime,xattr,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 0 0

cgroup /sys/fs/cgroup/cpu,cpuacct cgroup ro,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0

cgroup /sys/fs/cgroup/pids cgroup ro,nosuid,nodev,noexec,relatime,pids 0 0

cgroup /sys/fs/cgroup/hugetlb cgroup ro,nosuid,nodev,noexec,relatime,hugetlb 0 0

cgroup /sys/fs/cgroup/freezer cgroup ro,nosuid,nodev,noexec,relatime,freezer 0 0

cgroup /sys/fs/cgroup/cpuset cgroup ro,nosuid,nodev,noexec,relatime,cpuset 0 0

cgroup /sys/fs/cgroup/blkio cgroup ro,nosuid,nodev,noexec,relatime,blkio 0 0

cgroup /sys/fs/cgroup/net_cls,net_prio cgroup ro,nosuid,nodev,noexec,relatime,net_prio,net_cls 0 0

cgroup /sys/fs/cgroup/devices cgroup ro,nosuid,nodev,noexec,relatime,devices 0 0

cgroup /sys/fs/cgroup/perf_event cgroup ro,nosuid,nodev,noexec,relatime,perf_event 0 0

cgroup /sys/fs/cgroup/memory cgroup ro,nosuid,nodev,noexec,relatime,memory 0 0

mqueue /dev/mqueue mqueue rw,nosuid,nodev,noexec,relatime 0 0

/dev/mapper/centos_bogon-root /data ext4 rw,relatime,data=ordered 0 0

/dev/mapper/centos_bogon-root /dev/termination-log ext4 rw,relatime,data=ordered 0 0

/dev/mapper/centos_bogon-root /etc/resolv.conf ext4 rw,relatime,data=ordered 0 0

/dev/mapper/centos_bogon-root /etc/hostname ext4 rw,relatime,data=ordered 0 0

/dev/mapper/centos_bogon-root /etc/hosts ext4 rw,relatime,data=ordered 0 0

shm /dev/shm tmpfs rw,nosuid,nodev,noexec,relatime,size=65536k 0 0

tmpfs /var/run/secrets/kubernetes.io/serviceaccount tmpfs ro,relatime 0 0

proc /proc/bus proc ro,relatime 0 0

proc /proc/fs proc ro,relatime 0 0

proc /proc/irq proc ro,relatime 0 0

proc /proc/sys proc ro,relatime 0 0

proc /proc/sysrq-trigger proc ro,relatime 0 0

tmpfs /proc/acpi tmpfs ro,relatime 0 0

tmpfs /proc/kcore tmpfs rw,nosuid,size=65536k,mode=755 0 0

tmpfs /proc/keys tmpfs rw,nosuid,size=65536k,mode=755 0 0

tmpfs /proc/timer_list tmpfs rw,nosuid,size=65536k,mode=755 0 0

tmpfs /proc/timer_stats tmpfs rw,nosuid,size=65536k,mode=755 0 0

tmpfs /proc/sched_debug tmpfs rw,nosuid,size=65536k,mode=755 0 0

tmpfs /proc/scsi tmpfs ro,relatime 0 0

tmpfs /sys/firmware tmpfs ro,relatime 0 0

/data # df -h

Filesystem Size Used Available Use% Mounted on

overlay 9.7G 4.6G 4.6G 50% /

tmpfs 64.0M 0 64.0M 0% /dev

tmpfs 999.5M 0 999.5M 0% /sys/fs/cgroup

/dev/mapper/centos_bogon-root

9.7G 4.6G 4.6G 50% /data

/dev/mapper/centos_bogon-root

9.7G 4.6G 4.6G 50% /dev/termination-log

/dev/mapper/centos_bogon-root

9.7G 4.6G 4.6G 50% /etc/resolv.conf

/dev/mapper/centos_bogon-root

9.7G 4.6G 4.6G 50% /etc/hostname

/dev/mapper/centos_bogon-root

9.7G 4.6G 4.6G 50% /etc/hosts

shm 64.0M 0 64.0M 0% /dev/shm

tmpfs 999.5M 12.0K 999.5M 0% /var/run/secrets/kubernetes.io/serviceaccount

tmpfs 999.5M 0 999.5M 0% /proc/acpi

tmpfs 64.0M 0 64.0M 0% /proc/kcore

tmpfs 64.0M 0 64.0M 0% /proc/keys

tmpfs 64.0M 0 64.0M 0% /proc/timer_list

tmpfs 64.0M 0 64.0M 0% /proc/timer_stats

tmpfs 64.0M 0 64.0M 0% /proc/sched_debug

tmpfs 999.5M 0 999.5M 0% /proc/scsi

tmpfs 999.5M 0 999.5M 0% /sys/firmware