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云原生时代为什么还需要本地存储？

云原生时代，对于有存储应用的容器化上云，一般的解决思路是“计算存储分离”，计算层通过容器技术实现弹性伸缩，而相应的存储层也需要配合进行“动态挂载”，要实现动态挂载能力，使用基于网络的存储系统可能是最佳选择。然而，“网络”存储的磁盘 IO 性能差、自带高可用能力的中间件系统不需要存储层的“动态挂载” 等种种原因，业界对本地存储还是“青睐有加”。因此类似 rabbitmq、kafka 这样的中间件系统，优先使用本地盘，然后通过 k8s 增强自动化运维能力，解决原来磁盘手动管理问题，实现动态分配、扩容、隔离。

有没有更适合 k8s 的备份恢复方案？

传统的数据备份方案，一种是利用存储数据的服务端实现定期快照的备份，另一种是在每台目标服务器上部署专有备份 agent 并指定备份数据目录，定期把数据远程复制到外部存储上。这两种方式均存在“备份机制固化”、“数据恢复慢”等问题，无法适应容器化后的弹性、池化部署场景。我们需要更贴合 k8s 容器场景的备份恢复能力，实现一键备份、快速恢复。

整体计划

  1. 准备一个 k8s 集群，master 节点不跑 workload，最好能有 2 个 worker 节点；

  2. 部署 carina 云原生本地容器存储方案，测试本地盘自动化管理能力

  3. 部署 velero 云原生备份方案，测试数据备份和恢复能力

k8s 环境

  • 版本：v1.19.14

  • 集群规模：1master 2worker

  • 磁盘挂载情况：除了根目录使用了一块独立盘，初始状态未使用其他的磁盘

部署 carina

1、部署脚本

可以参考官方文档[1]，部署方式区分 1.22 版本前后，大概率由于 1.22 版本很多 API 发生变更。

2、本地裸盘准备：

为每个 worker 挂载一块裸盘，建议至少 20G，carina 默认会占用 10G 磁盘空间，作为存储管理元数据。由于我自己使用了谷歌云，可以通过如下步骤实现：第一个是 ssd，第二个是 hdd。

gcloud apply ssd

gcloud apply hdd

3、确认 carina 组件能够搜索并读取到新挂载的裸盘，需要通过修改 carina 默认扫描本地盘的策略：

# 通过以下命令查看配置扫描策略的configmap
# 官网说明文档：https://github.com/carina-io/carina/blob/main/docs/manual/disk-manager.md
> kubectl describe cm carina-csi-config -n kube-system
Name:         carina-csi-config
Namespace:    kube-system
Labels:       class=carina
Annotations:  <none>Data
====
config.json:
----
{# 根据google cloud磁盘的命名规则作了更改，匹配以sd开头的磁盘"diskSelector": ["sd+"],# 扫描周期180秒"diskScanInterval": "180","diskGroupPolicy": "type","schedulerStrategy": "spradout"
}

4、通过查看 carina 组件状态，确认本地盘已经被识别

> kubectl get node u20-w1 -o template --template={{.status.capacity}}
map[carina.storage.io/carina-vg-hdd:200 carina.storage.io/carina-vg-ssd:20 cpu:2 ephemeral-storage:30308240Ki hugepages-1Gi:0 hugepages-2Mi:0 memory:4022776Ki pods:110]> kubectl get node u20-w1 -o template --template={{.status.allocatable}}
map[carina.storage.io/carina-vg-hdd:189 carina.storage.io/carina-vg-ssd:1 cpu:2 ephemeral-storage:27932073938 hugepages-1Gi:0 hugepages-2Mi:0 memory:3920376Ki pods:110]# 可以看到hdd容量已经变成200了、SSD容量变成20,为什么能区分ssd和hdd呢？这里先按下不表
# 这里也能看到预留了10G空间不可使用，因为200G新盘刚加入只有189G（考虑到有磁盘单位换算带来的误差）可用。
# 这些信息很重要，当pv创建时会从该node信息中获取当前节点磁盘容量，然后根据pv调度策略进行调度# 还有个集中查看磁盘使用情况的入口
> kubectl get configmap carina-node-storage -n kube-system -o json | jq .data.node
[{"allocatable.carina.storage.io/carina-vg-hdd":"189","allocatable.carina.storage.io/carina-vg-ssd":"1","capacity.carina.storage.io/carina-vg-hdd":"200","capacity.carina.storage.io/carina-vg-ssd":"20","nodeName":"u20-w1"},{"allocatable.carina.storage.io/carina-vg-hdd":"189","allocatable.carina.storage.io/carina-vg-ssd":"0","capacity.carina.storage.io/carina-vg-hdd":"200","capacity.carina.storage.io/carina-vg-ssd":"0","nodeName":"u20-w2"}
]

5、为什么能自动识别 hdd 和 sdd 呢？

# carina-node服务启动时会自动将节点上磁盘按照SSD和HDD进行分组并组建成vg卷组
# 使用命令lsblk --output NAME,ROTA查看磁盘类型，ROTA=1为HDD磁盘 ROTA=0为SSD磁盘
# 支持文件存储及块设备存储，其中文件存储支持xfs和ext4格式
# 下面是事前声明的storageclass，用来自动创建pv
> k get sc csi-carina-sc -o json | jq .metadata.annotations
{"kubectl.kubernetes.io/last-applied-configuration":{"allowVolumeExpansion":true,"apiVersion":"storage.k8s.io/v1","kind":"StorageClass","metadata":{"annotations":{},"name":"csi-carina-sc"},"mountOptions":["rw"],"parameters":{"csi.storage.k8s.io/fstype":"ext4"},"provisioner":"carina.storage.io","reclaimPolicy":"Delete","volumeBindingMode":"WaitForFirstConsumer"}
}

测试 carina 自动分配 PV 能力

1、想要 carina 具备自动创建 PV 能力，需要先声明并创建 storageclass。

# 创建storageclass的yaml
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:name: csi-carina-sc
provisioner: carina.storage.io # 这是该CSI驱动的名称，不允许更改
parameters:# 支持xfs,ext4两种文件格式，如果不填则默认ext4csi.storage.k8s.io/fstype: ext4# 这是选择磁盘分组，该项目会自动将SSD及HDD磁盘分组# SSD：ssd HDD: hdd# 如果不填会随机选择磁盘类型#carina.storage.io/disk-type: hdd
reclaimPolicy: Delete
allowVolumeExpansion: true # 支持扩容，定为true便可
# WaitForFirstConsumer表示被容器绑定调度后再创建pv
volumeBindingMode: WaitForFirstConsumer
# 支持挂载参数设置，这里配置为读写模式
mountOptions:- rw

kubectl apply 后，可以通过以下命令确认：

> kubectl get sc csi-carina-sc -o json | jq .metadata.annotations
{"kubectl.kubernetes.io/last-applied-configuration":{"allowVolumeExpansion":true,"apiVersion":"storage.k8s.io/v1","kind":"StorageClass","metadata":{"annotations":{},"name":"csi-carina-sc"},"mountOptions":["rw"],"parameters":{"csi.storage.k8s.io/fstype":"ext4"},"provisioner":"carina.storage.io","reclaimPolicy":"Delete","volumeBindingMode":"WaitForFirstConsumer"}
}

2、部署带存储的测试应用

测试场景比较简单，使用简单 nginx 服务，挂载数据盘，存放自定义 html 页面。

# pvc for nginx html
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:name: csi-carina-pvc-bignamespace: default
spec:accessModes:- ReadWriteOnceresources:requests:storage: 10Gi# 指定carina的storageclass名称storageClassName: csi-carina-scvolumeMode: Filesystem# nginx deployment yaml
---
apiVersion: apps/v1
kind: Deployment
metadata:name: carina-deployment-bignamespace: defaultlabels:app: web-server-big
spec:replicas: 1selector:matchLabels:app: web-server-bigtemplate:metadata:labels:app: web-server-bigspec:containers:- name: web-serverimage: nginx:latestimagePullPolicy: "IfNotPresent"volumeMounts:- name: mypvc-bigmountPath: /usr/share/nginx/html # nginx默认将页面内容存放在这个文件夹volumes:- name: mypvc-bigpersistentVolumeClaim:claimName: csi-carina-pvc-bigreadOnly: false

查看测试应用运行情况：

# pvc
> kubectl get pvc
NAME                 STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS    AGE
csi-carina-pvc-big   Bound    pvc-74e683f9-d2a4-40a0-95db-85d1504fd961   10Gi       RWO            csi-carina-sc   109s# pv
> kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                        STORAGECLASS    REASON   AGE
pvc-74e683f9-d2a4-40a0-95db-85d1504fd961   10Gi       RWO            Delete           Bound    default/csi-carina-pvc-big   csi-carina-sc            109s# nginx pod
> kubectl get po -l app=web-server-big -o wide
NAME                                    READY   STATUS    RESTARTS   AGE     IP          NODE     NOMINATED NODE   READINESS GATES
carina-deployment-big-6b78fb9fd-mwf8g   1/1     Running   0          3m48s   10.0.2.69   u20-w2   <none>           <none># 查看相关node的磁盘使用情况，可分配的大小已经发生变化，缩小了10
> kubectl get node u20-w2 -o template --template={{.status.allocatable}}
map[carina.storage.io/carina-vg-hdd:179 carina.storage.io/carina-vg-ssd:0 cpu:2 ephemeral-storage:27932073938 hugepages-1Gi:0 hugepages-2Mi:0 memory:3925000Ki pods:110]

登录运行测试服务的 node 节点，查看磁盘挂载情况：

# 磁盘分配情况如下，有meta和pool两个lvm
> lsblk
...
sdb       8:16   0   200G  0 disk
├─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961_tmeta
│       253:0    0    12M  0 lvm
│ └─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961-tpool
│       253:2    0    10G  0 lvm
│   ├─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961
│   │   253:3    0    10G  1 lvm
│   └─carina--vg--hdd-volume--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961
│       253:4    0    10G  0 lvm  /var/lib/kubelet/pods/57ded9fb-4c82-4668-b77b-7dc02ba05fc2/volumes/kubernetes.io~
└─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961_tdata253:1    0    10G  0 lvm└─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961-tpool253:2    0    10G  0 lvm├─carina--vg--hdd-thin--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961│   253:3    0    10G  1 lvm└─carina--vg--hdd-volume--pvc--74e683f9--d2a4--40a0--95db--85d1504fd961253:4    0    10G  0 lvm  /var/lib/kubelet/pods/57ded9fb-4c82-4668-b77b-7dc02ba05fc2/volumes/kubernetes.io~
# vgs
> vgsVG            #PV #LV #SN Attr   VSize    VFreecarina-vg-hdd   1   2   0 wz--n- <200.00g 189.97g
# lvs
> lvsLV                                              VG            Attr       LSize  Pool                                          Origin Data%  Meta%  Move Log Cpy%Sync Convertthin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961   carina-vg-hdd twi-aotz-- 10.00g                                                      2.86   11.85volume-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961 carina-vg-hdd Vwi-aotz-- 10.00g thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961        2.86# 使用lvm命令行工具查看磁盘挂载信息
> pvsPV         VG            Fmt  Attr PSize    PFree/dev/sdb   carina-vg-hdd lvm2 a--  <200.00g 189.97g
> pvdisplay--- Physical volume ---PV Name               /dev/sdbVG Name               carina-vg-hddPV Size               <200.00 GiB / not usable 3.00 MiBAllocatable           yesPE Size               4.00 MiBTotal PE              51199Free PE               48633Allocated PE          2566PV UUID               Wl6ula-kD54-Mj5H-ZiBc-aHPB-6RHI-mXs9R9> lvsLV                                              VG            Attr       LSize  Pool                                          Origin Data%  Meta%  Move Log Cpy%Sync Convertthin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961   carina-vg-hdd twi-aotz-- 10.00g                                                      2.86   11.85volume-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961 carina-vg-hdd Vwi-aotz-- 10.00g thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961        2.86
> lvdisplay--- Logical volume ---LV Name                thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961VG Name                carina-vg-hddLV UUID                kB7DFm-dl3y-lmop-p7os-3EW6-4Toy-slX7qnLV Write Access        read/write (activated read only)LV Creation host, time u20-w2, 2021-11-09 05:31:18 +0000LV Pool metadata       thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961_tmetaLV Pool data           thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961_tdataLV Status              available# open                 2LV Size                10.00 GiBAllocated pool data    2.86%Allocated metadata     11.85%Current LE             2560Segments               1Allocation             inheritRead ahead sectors     auto- currently set to     256Block device           253:2--- Logical volume ---LV Path                /dev/carina-vg-hdd/volume-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961LV Name                volume-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961VG Name                carina-vg-hddLV UUID                vhDYe9-KzPc-qqJk-2o1f-TlCv-0TDL-643b8rLV Write Access        read/writeLV Creation host, time u20-w2, 2021-11-09 05:31:19 +0000LV Pool name           thin-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961LV Status              available# open                 1LV Size                10.00 GiBMapped size            2.86%Current LE             2560Segments               1Allocation             inheritRead ahead sectors     auto- currently set to     256Block device           253:4

进入磁盘，添加自定义内容，查看存储情况

# 进入容器内，创建自定义页面
> kubectl exec -ti carina-deployment-big-6b78fb9fd-mwf8g -- /bin/bash
/# cd /usr/share/nginx/html/
/usr/share/nginx/html# ls
lost+found
/usr/share/nginx/html# echo "hello carina" > index.html
/usr/share/nginx/html# curl localhost
hello carina
/usr/share/nginx/html# echo "test carina" > test.html
/usr/share/nginx/html# curl localhost/test.html
test carina# 登录node节点，进入挂载点，查看上面刚刚创建的内容
> df -h
...
/dev/carina/volume-pvc-74e683f9-d2a4-40a0-95db-85d1504fd961  9.8G   37M  9.7G   1% /var/lib/kubelet/pods/57ded9fb-4c82-4668-b77b-7dc02ba05fc2/volumes/kubernetes.io~csi/pvc-74e683f9-d2a4-40a0-95db-85d1504fd961/mount
> cd /var/lib/kubelet/pods/57ded9fb-4c82-4668-b77b-7dc02ba05fc2/volumes/kubernetes.io~csi/pvc-74e683f9-d2a4-40a0-95db-85d1504fd961/mount
> ll
total 32
drwxrwsrwx 3 root root  4096 Nov  9 05:54 ./
drwxr-x--- 3 root root  4096 Nov  9 05:31 ../
-rw-r--r-- 1 root root    13 Nov  9 05:54 index.html
drwx------ 2 root root 16384 Nov  9 05:31 lost+found/
-rw-r--r-- 1 root root    12 Nov  9 05:54 test.html

部署 velero

1、下载 velero 命令行工具，本次使用的是 1.7.0 版本

> wget <https://github.com/vmware-tanzu/velero/releases/download/v1.7.0/velero-v1.7.0-linux-amd64.tar.gz>
> tar -xzvf velero-v1.7.0-linux-amd64.tar.gz
> cd velero-v1.7.0-linux-amd64 && cp velero /usr/local/bin/
> velero
Velero is a tool for managing disaster recovery, specifically for Kubernetes
cluster resources. It provides a simple, configurable, and operationally robust
way to back up your application state and associated data.If you're familiar with kubectl, Velero supports a similar model, allowing you to
execute commands such as 'velero get backup' and 'velero create schedule'. The same
operations can also be performed as 'velero backup get' and 'velero schedule create'.Usage:velero [command]Available Commands:backup            Work with backupsbackup-location   Work with backup storage locationsbug               Report a Velero bugclient            Velero client related commandscompletion        Generate completion scriptcreate            Create velero resourcesdebug             Generate debug bundledelete            Delete velero resourcesdescribe          Describe velero resourcesget               Get velero resourceshelp              Help about any commandinstall           Install Veleroplugin            Work with pluginsrestic            Work with resticrestore           Work with restoresschedule          Work with schedulessnapshot-location Work with snapshot locationsuninstall         Uninstall Veleroversion           Print the velero version and associated image

2、部署 minio 对象存储，作为 velero 后端存储

为了部署 velero 服务端，需要优先准备好一个后端存储。velero 支持很多类型的后端存储，详细看这里：https://velero.io/docs/v1.7/supported-providers/[2]。只要遵循 AWS S3 存储接口规范的，都可以对接，本次使用兼容 S3 接口的 minio 服务作为后端存储，部署 minio 方式如下，其中就使用到了 carina storageclass 提供磁盘创建能力：

# 参考文档：https://velero.io/docs/v1.7/contributions/minio/
# 统一部署在minio命名空间
---
apiVersion: v1
kind: Namespace
metadata:name: minio
# 为minio后端存储申请8G磁盘空间，走的就是carina storageclass
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:name: minio-storage-pvcnamespace: minio
spec:accessModes:- ReadWriteOnceresources:requests:storage: 8GistorageClassName: csi-carina-sc # 指定carina storageclassvolumeMode: Filesystem
---
apiVersion: apps/v1
kind: Deployment
metadata:namespace: minioname: miniolabels:component: minio
spec:strategy:type: Recreateselector:matchLabels:component: miniotemplate:metadata:labels:component: miniospec:volumes:- name: storagepersistentVolumeClaim:claimName: minio-storage-pvcreadOnly: false- name: configemptyDir: {}containers:- name: minioimage: minio/minio:latestimagePullPolicy: IfNotPresentargs:- server- /storage- --config-dir=/config- --console-address ":9001" # 配置前端页面的暴露端口env:- name: MINIO_ACCESS_KEYvalue: "minio"- name: MINIO_SECRET_KEYvalue: "minio123"ports:- containerPort: 9000- containerPort: 9001volumeMounts:- name: storagemountPath: "/storage"- name: configmountPath: "/config"
# 使用nodeport创建svc，提供对外服务能力，包括前端页面和后端API
---
apiVersion: v1
kind: Service
metadata:namespace: minioname: miniolabels:component: minio
spec:# ClusterIP is recommended for production environments.# Change to NodePort if needed per documentation,# but only if you run Minio in a test/trial environment, for example with Minikube.type: NodePortports:- name: consoleport: 9001targetPort: 9001- name: apiport: 9000targetPort: 9000protocol: TCPselector:component: minio# 初始化创建velero的bucket
---
apiVersion: batch/v1
kind: Job
metadata:namespace: minioname: minio-setuplabels:component: minio
spec:template:metadata:name: minio-setupspec:restartPolicy: OnFailurevolumes:- name: configemptyDir: {}containers:- name: mcimage: minio/mc:latestimagePullPolicy: IfNotPresentcommand:- /bin/sh- -c- "mc --config-dir=/config config host add velero <http://minio:9000> minio minio123 && mc --config-dir=/config mb -p velero/velero"volumeMounts:- name: configmountPath: "/config"

部署 minio 完成后如下所示：

> kubectl get all -n minio
NAME                         READY   STATUS    RESTARTS   AGE
pod/minio-686755b769-k6625   1/1     Running   0          6d15hNAME            TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)                          AGE
service/minio   NodePort   10.98.252.130   <none>        36369:31943/TCP,9000:30436/TCP   6d15hNAME                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/minio   1/1     1            1           6d15hNAME                               DESIRED   CURRENT   READY   AGE
replicaset.apps/minio-686755b769   1         1         1       6d15h
replicaset.apps/minio-c9c844f67    0         0         0       6d15hNAME                    COMPLETIONS   DURATION   AGE
job.batch/minio-setup   1/1           114s       6d15h

打开 minio 页面，使用部署时定义的账号登录：

minio login

minio dashboard

3、安装 velero 服务端

# 注意添加--use-restric，开启pv数据备份
# 注意最后一行，使用了k8s svc域名服务，<http://minio.minio.svc:9000>
velero install--provider aws--plugins velero/velero-plugin-for-aws:v1.2.1--bucket velero--secret-file ./minio-cred--namespace velero--use-restic--use-volume-snapshots=false--backup-location-config region=minio,s3ForcePathStyle="true",s3Url=http://minio.minio.svc:9000

安装完成后如下所示：

# 除了velero之外，
# 还有restic，它是负责备份pv数据的核心组件，需要保证每个节点上的pv都能备份，因此它使用了daemonset模式
# 详细参考：<https://velero.io/docs/v1.7/restic/>
> kubectl get all -n velero
NAME                          READY   STATUS    RESTARTS   AGE
pod/restic-g5q5k              1/1     Running   0          6d15h
pod/restic-jdk7h              1/1     Running   0          6d15h
pod/restic-jr8f7              1/1     Running   0          5d22h
pod/velero-6979cbd56b-s7v99   1/1     Running   0          5d21hNAME                    DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR   AGE
daemonset.apps/restic   3         3         3       3            3           <none>          6d15hNAME                     READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/velero   1/1     1            1           6d15hNAME                                DESIRED   CURRENT   READY   AGE
replicaset.apps/velero-6979cbd56b   1         1         1       6d15h

使用 velero 备份应用及其数据

  1. 使用 velero backup 命令备份带 pv 的测试应用

# 通过--selector选项指定应用标签
# 通过--default-volumes-to-restic选项显式声明使用restric备份pv数据
> velero backup create nginx-backup --selector app=web-server-big --default-volumes-to-restic
I1109 09:14:31.380431 1527737 request.go:655] Throttling request took 1.158837643s, request: GET:<https://10.140.0.8:6443/apis/networking.istio.io/v1beta1?timeout=32s>
Backup request "nginx-pv-backup" submitted successfully.
Run `velero backup describe nginx-pv-backup` or `velero backup logs nginx-pv-backup` for more details.# 无法查看执行备份的日志，说是无法访问minio接口，很奇怪
> velero backup logs nginx-pv-backup
I1109 09:15:04.840199 1527872 request.go:655] Throttling request took 1.146201139s, request: GET:<https://10.140.0.8:6443/apis/networking.k8s.io/v1beta1?timeout=32s>
An error occurred: Get "<http://minio.minio.svc:9000/velero/backups/nginx-pv-backup/nginx-pv-backup-logs.gz?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=minio%2F20211109%2Fminio%2Fs3%2Faws4_request&X-Amz-Date=20211109T091506Z&X-Amz-Expires=600&X-Amz-SignedHeaders=host&X-Amz-Signature=b48c1988101b544329effb67aee6a7f83844c4630eb1d19db30f052e3603b9b2>": dial tcp: lookup minio.minio.svc on 127.0.0.53:53: no such host# 可以看到详细的备份执行信息，
# 这个备份是会过期的，默认是1个月有效期
> velero backup describe nginx-pv-backup
I1109 09:15:25.834349 1527945 request.go:655] Throttling request took 1.147122392s, request: GET:<https://10.140.0.8:6443/apis/pkg.crossplane.io/v1beta1?timeout=32s>
Name:         nginx-pv-backup
Namespace:    velero
Labels:       velero.io/storage-location=default
Annotations:  velero.io/source-cluster-k8s-gitversion=v1.19.14velero.io/source-cluster-k8s-major-version=1velero.io/source-cluster-k8s-minor-version=19Phase:  CompletedErrors:    0
Warnings:  1Namespaces:Included:  *Excluded:  <none>Resources:Included:        *Excluded:        <none>Cluster-scoped:  autoLabel selector:  app=web-server-bigStorage Location:  defaultVelero-Native Snapshot PVs:  autoTTL:  720h0m0sHooks:  <none>Backup Format Version:  1.1.0Started:    2021-11-09 09:14:32 +0000 UTC
Completed:  2021-11-09 09:15:05 +0000 UTCExpiration:  2021-12-09 09:14:32 +0000 UTCTotal items to be backed up:  9
Items backed up:              9Velero-Native Snapshots: <none included>Restic Backups (specify --details for more information):Completed:  1

2、打开 minio 页面，查看备份数据的明细

在**backups文件夹下有个nginx-pv-backup**文件夹，里面有很多压缩文件，有机会可以分析下。

在 restric 文件夹下，产生了一堆数据，查了资料，它是加密保存的，因此无法显性看出备份 pv 的数据。接下来我们尝试下恢复能力，就能验证其数据备份能力。

使用 velero 恢复应用及其数据

1、删除测试应用及其数据

# delete nginx deployment
> kubectl delete deploy carina-deployment-big# delete nginx pvc
# 检查pv是否已经释放
> kubectl delete pvc csi-carina-pvc-big

2、通过 velero restore 恢复测试应用和数据

# 恢复
> velero restore create --from-backup nginx-pv-backup
Restore request "nginx-pv-backup-20211109094323" submitted successfully.
Run `velero restore describe nginx-pv-backup-20211109094323` or `velero restore logs nginx-pv-backup-20211109094323` for more details.
root@u20-m1:/home/legendarilylwq# velero restore describe nginx-pv-backup-20211109094323
I1109 09:43:50.028122 1534182 request.go:655] Throttling request took 1.161022334s, request: GET:<https://10.140.0.8:6443/apis/networking.k8s.io/v1?timeout=32s>
Name:         nginx-pv-backup-20211109094323
Namespace:    velero
Labels:       <none>
Annotations:  <none>Phase:                                 InProgress
Estimated total items to be restored:  9
Items restored so far:                 9Started:    2021-11-09 09:43:23 +0000 UTC
Completed:  <n/a>Backup:  nginx-pv-backupNamespaces:Included:  all namespaces found in the backupExcluded:  <none>Resources:Included:        *Excluded:        nodes, events, events.events.k8s.io, backups.velero.io, restores.velero.io, resticrepositories.velero.ioCluster-scoped:  autoNamespace mappings:  <none>Label selector:  <none>Restore PVs:  autoRestic Restores (specify --details for more information):New:  1Preserve Service NodePorts:  auto> velero restore get
NAME                             BACKUP            STATUS      STARTED                         COMPLETED                       ERRORS   WARNINGS   CREATED                         SELECTOR
nginx-pv-backup-20211109094323   nginx-pv-backup   Completed   2021-11-09 09:43:23 +0000 UTC   2021-11-09 09:44:14 +0000 UTC   0        2          2021-11-09 09:43:23 +0000 UTC   <none>

3、验证测试应用和数据是否恢复

# 查看po、pvc、pv是否自动恢复创建
> kubectl get po
NAME                                    READY   STATUS    RESTARTS   AGE
carina-deployment-big-6b78fb9fd-mwf8g   1/1     Running   0          93s
kubewatch-5ffdb99f79-87qbx              2/2     Running   0          19d
static-pod-u20-w1                       1/1     Running   15         235d> kubectl get pvc
NAME                 STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS    AGE
csi-carina-pvc-big   Bound    pvc-e81017c5-0845-4bb1-8483-a31666ad3435   10Gi       RWO            csi-carina-sc   100s> kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                        STORAGECLASS    REASON   AGE
pvc-a07cac5e-c38b-454d-a004-61bf76be6516   8Gi        RWO            Delete           Bound    minio/minio-storage-pvc      csi-carina-sc            6d17h
pvc-e81017c5-0845-4bb1-8483-a31666ad3435   10Gi       RWO            Delete           Bound    default/csi-carina-pvc-big   csi-carina-sc            103s> kubectl get deploy
NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
carina-deployment-big   1/1     1            1           2m20s
kubewatch               1/1     1            1           327d# 进入容器，验证自定义页面是否还在
> kubectl exec -ti carina-deployment-big-6b78fb9fd-mwf8g -- /bin/bash
/# cd  /usr/share/nginx/html/
/usr/share/nginx/html# ls -l
total 24
-rw-r--r-- 1 root root    13 Nov  9 05:54 index.html
drwx------ 2 root root 16384 Nov  9 05:31 lost+found
-rw-r--r-- 1 root root    12 Nov  9 05:54 test.html
/usr/share/nginx/html# curl localhost
hello carina
/usr/share/nginx/html# curl localhost/test.html
test carina

4、仔细分析恢复过程

下面是恢复后的测试应用的详细信息，有个新增的 init container，名叫**restric-wait**，它自身使用了一个磁盘挂载。

> kubectl describe po carina-deployment-big-6b78fb9fd-mwf8g
Name:         carina-deployment-big-6b78fb9fd-mwf8g
Namespace:    default
Priority:     0
Node:         u20-w2/10.140.0.13
Start Time:   Tue, 09 Nov 2021 09:43:47 +0000
Labels:       app=web-server-bigpod-template-hash=6b78fb9fdvelero.io/backup-name=nginx-pv-backupvelero.io/restore-name=nginx-pv-backup-20211109094323
Annotations:  <none>
Status:       Running
IP:           10.0.2.227
IPs:IP:           10.0.2.227
Controlled By:  ReplicaSet/carina-deployment-big-6b78fb9fd
Init Containers:restic-wait:Container ID:  containerd://ec0ecdf409cc60790fe160d4fc3ba0639bbb1962840622dc20dcc6ccb10e9b5aImage:         velero/velero-restic-restore-helper:v1.7.0Image ID:      docker.io/velero/velero-restic-restore-helper@sha256:6fce885ce23cf15b595b5d3b034d02a6180085524361a15d3486cfda8022fa03Port:          <none>Host Port:     <none>Command:/velero-restic-restore-helperArgs:f4ddbfca-e3b4-4104-b36e-626d29e99334State:          TerminatedReason:       CompletedExit Code:    0Started:      Tue, 09 Nov 2021 09:44:12 +0000Finished:     Tue, 09 Nov 2021 09:44:14 +0000Ready:          TrueRestart Count:  0Limits:cpu:     100mmemory:  128MiRequests:cpu:     100mmemory:  128MiEnvironment:POD_NAMESPACE:  default (v1:metadata.namespace)POD_NAME:       carina-deployment-big-6b78fb9fd-mwf8g (v1:metadata.name)Mounts:/restores/mypvc-big from mypvc-big (rw)/var/run/secrets/kubernetes.io/serviceaccount from default-token-kw7rf (ro)
Containers:web-server:Container ID:   containerd://f3f49079dcd97ac8f65a92f1c42edf38967a61762b665a5961b4cb6e60d13a24Image:          nginx:latestImage ID:       docker.io/library/nginx@sha256:644a70516a26004c97d0d85c7fe1d0c3a67ea8ab7ddf4aff193d9f301670cf36Port:           <none>Host Port:      <none>State:          RunningStarted:      Tue, 09 Nov 2021 09:44:14 +0000Ready:          TrueRestart Count:  0Environment:    <none>Mounts:/usr/share/nginx/html from mypvc-big (rw)/var/run/secrets/kubernetes.io/serviceaccount from default-token-kw7rf (ro)
Conditions:
Type              StatusInitialized       TrueReady             TrueContainersReady   TruePodScheduled      True
Volumes:mypvc-big:Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)ClaimName:  csi-carina-pvc-bigReadOnly:   falsedefault-token-kw7rf:Type:        Secret (a volume populated by a Secret)SecretName:  default-token-kw7rfOptional:    false
QoS Class:       Burstable
Node-Selectors:  <none>
Tolerations:     node.kubernetes.io/not-ready:NoExecute op=Exists for 300snode.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:Type     Reason                  Age    From                     Message----     ------                  ----   ----                     -------Warning  FailedScheduling        7m20s  carina-scheduler         pod 6b8cf52c-7440-45be-a117-8f29d1a37f2c is in the cache, so can't be assumedWarning  FailedScheduling        7m20s  carina-scheduler         pod 6b8cf52c-7440-45be-a117-8f29d1a37f2c is in the cache, so can't be assumedNormal   Scheduled               7m18s  carina-scheduler         Successfully assigned default/carina-deployment-big-6b78fb9fd-mwf8g to u20-w2Normal   SuccessfulAttachVolume  7m18s  attachdetach-controller  AttachVolume.Attach succeeded for volume "pvc-e81017c5-0845-4bb1-8483-a31666ad3435"Normal   Pulling                 6m59s  kubelet                  Pulling image "velero/velero-restic-restore-helper:v1.7.0"Normal   Pulled                  6m54s  kubelet                  Successfully pulled image "velero/velero-restic-restore-helper:v1.7.0" in 5.580228382sNormal   Created                 6m54s  kubelet                  Created container restic-waitNormal   Started                 6m53s  kubelet                  Started container restic-waitNormal   Pulled                  6m51s  kubelet                  Container image "nginx:latest" already present on machineNormal   Created                 6m51s  kubelet                  Created container web-serverNormal   Started                 6m51s  kubelet                  Started container web-server

感兴趣希望深入研究整体恢复应用的过程，可以参考官网链接：https://velero.io/docs/v1.7/restic/#customize-restore-helper-container[3]，代码实现看这里：https://github.com/vmware-tanzu/velero/blob/main/pkg/restore/restic_restore_action.go[4]

以上通过 step by step 演示了如何使用 carina 和 velero 实现容器存储自动化管理和数据的快速备份和恢复，这次虽然只演示了部分功能（还有如磁盘读写限速、按需备份恢复等高级功能等待大家去尝试），但从结果可以看出，已实现了有存储应用的快速部署、备份和恢复，给 k8s 集群异地灾备方案带来了“简单”的选择。我自己也准备把 Wordpress 博客也用这个方式备份起来。

参考链接