说明：

Kubernetes中使用GlusterFS作为持久化存储，要提供storageClass使用需要依赖Heketi工具。Heketi是一个具有resetful接口的glusterfs管理程序，作为kubernetes的Storage存储的external provisioner。 “Heketi提供了一个RESTful管理界面，可用于管理GlusterFS卷的生命周期。借助Heketi，像OpenStack Manila，Kubernetes和OpenShift这样的云服务可以动态地配置GlusterFS卷和任何支持的持久性类型。Heketi将自动确定整个集群的brick位置，确保将brick及其副本放置在不同的故障域中。Heketi还支持任意数量的GlusterFS集群，允许云服务提供网络文件存储，而不受限于单个GlusterFS集群。
heketi：提供基于RESTful接口管理glusterfs的功能，可以方便的创建集群管理glusterfs的node，device，volume；与k8s结合可以创建动态的PV，扩展glusterfs存储的动态管理功能。主要用来管理glusterFS volume的生命周期，初始化时候就要分配好裸磁盘(未格式化)设备.

注意事项：

安装Glusterfs客户端：每个kubernetes集群的节点需要安装gulsterfs的客户端，如glusterfs-cli,glusterfs-fuse.主要用于在每个node节点挂载volume。
加载内核模块：每个kubernetes集群的节点运行modprobe dm_thin_pool，加载内核模块。
高可用(至少三个节点)：至少需要节点用来部署glusterfs集群，并且这3个节点每个节点需要至少一个空余的磁盘。

基础设施要求:

正在运行的glusterfs集群，至少有三个node节点，每个节点至少有一个可用的裸块设备（如EBS卷或本地磁盘,就是没有格式化的）.
用于运行GlusterFS节点必须为GlusterFS通信打开相应的端口（如果开启了防火墙的情况下，没开防火墙就不需要这些操作）。

安装GlusterFS

安装依赖及常用工具包：
yum -y install flex bison openssl openssl-devel libxml2-devel gcc lrzsz vim*
查找gluster的最新软件仓库：
yum search centos-release-gluster
安装最新版本的gluster软件仓库：
yum install centos-release-gluster7.noarch -y
安装gluster源，并安装glusterfs及相关软件包
yum install glusterfs glusterfs-server glusterfs-cli glusterfs-geo-replication glusterfs-rdma -y
客户端安装GlusterFS客户端软件
yum install glusterfs-fuse glusterfs-cli
启动Glusterd服务
systemctl start glusterd
systemctl enable glusterd --now //设开机自启，并立即启动服务

在任意一个节点上添加信任节点
gluster peer probe node99
gluster peer probe node110
gluster peer probe node145
gluster peer probe node108

查看节点状态：
gluster peer status //查看节点状态

Number of Peers: 3
Hostname: node110
Uuid: 5f13e231-25cf-475b-81ca-22122b1bfe55
State: Peer in Cluster (Connected)
Other names:
10.14.151.110

Hostname: node99
Uuid: 7988f095-db67-47ee-913b-c232d1d4e954
State: Peer in Cluster (Connected)

Hostname: node145
Uuid: 36e84b55-dab7-4551-9b44-490039d1bdf6
State: Peer in Cluster (Connected)
Other names:
10.14.151.145

创建复制卷

mkdir /glusterfs/storage1/rep_vol1
gluster volume create rep_vol1 replica 2 node99:/glusterfs/storage1/rep_vol1 node108:/glusterfs/storage1/rep_vol1

创建分布式卷

gluster volume create vdisk1 node108:/brick1 node110:/brick1 brick node145:/brick1 force

创建分布式复制卷

gluster volume create fbfz replica 2 transport tcp node108:/gluster/fbfz1 node110:/gluster/fbfz1 node145:/gluster/fbfz1 node108:/gluster/fbfz2 node110:/gluster/fbfz2 node145:/gluster/fbfz2 force

启动卷
gluster volume start rep_vol1
查看卷状态
gluster volume status
gluster volume info
客户端测试挂载卷
mount -t glusterfs node108:rep_vol /tmp/aaa
mount -t glusterfs node145:fbfz /mnt/fbfz
客户端测试卷数据存储
for i in `seq -w 1 3`;do cp -rp /var/log/messages /tmp/aaa/test-$i;done

ls /tmp/aaa
111  1.txt  2.txt  anaconda-ks.cfg  test-1  test-2  test-3

其他备用操作

停止卷：
gluster volume stop vdisk2
删除卷：
gluster volume delete vdisk2
将某个存储节点主机从信任池中删除：
gluster peer detach node2

安装Heketi

Heketi是由golang编写，直接静态编译运行二进制即可，也可以通过yum安装以及docker部署，主要会产生db文件存储cluster、node、device、volume等信息。

安装二进制包
wget -c https://github.com/heketi/heketi/releases/download/v8.0.0/heketi-v8.0.0.linux.amd64.tar.gz tar zxvf heketi-v9.0.0.linux.amd64.tar.gz
mkdir -pv /opt/heketi/{bin,conf,data}
cp heketi/heketi.json /opt/heketi/conf/
cp heketi/{heketi,heketi-cli} /opt/heketi/bin/

创建ssh-key

我们glusterFS部署在k8s集群外，所以heketi通过ssh管理glusterFS。需要创建免秘钥登陆到所有glusterFS节点。
ssh-keygen -f /opt/heketi/conf/heketi_key -t rsa -N ''
ssh-copy-id -i /opt/heketi/conf/heketi_key.pub root@node108 -p 2222
ssh-copy-id -i /opt/heketi/conf/heketi_key.pub root@node110 -p 2222
ssh-copy-id -i /opt/heketi/conf/heketi_key.pub root@node145 -p 2222

配置文件修改

{
  "_port_comment": "Heketi Server Port Number",
  "port": "18080",
  "_use_auth": "Enable JWT authorization. Please enable for deployment",
  "use_auth": true,
  "_jwt": "Private keys for access",
  "jwt": {
    "_admin": "Admin has access to all APIs",
    "admin": {
      "key": "adminkey"
    },
    "_user": "User only has access to /volumes endpoint",
    "user": {
      "key": "userkey"
    }
  },
  "_glusterfs_comment": "GlusterFS Configuration",
  "glusterfs": {
    "_executor_comment": [
      "Execute plugin. Possible choices: mock, ssh",
      "mock: This setting is used for testing and development.",
      "      It will not send commands to any node.",
      "ssh:  This setting will notify Heketi to ssh to the nodes.",
      "      It will need the values in sshexec to be configured.",
      "kubernetes: Communicate with GlusterFS containers over",
     "            Kubernetes exec api."
    ],
    "executor": "ssh",
    "_sshexec_comment": "SSH username and private key file information",
    "sshexec": {
      "keyfile": "/opt/heketi/conf/heketi_key",
      "user": "root",
      "port": "2222",
      "fstab": "/etc/fstab"
    },
    "_kubeexec_comment": "Kubernetes configuration",
    "kubeexec": {
      "host" :"https://kubernetes.host:8443",
      "cert" : "/path/to/crt.file",
      "insecure": false,
      "user": "kubernetes username",
      "password": "password for kubernetes user",
      "namespace": "OpenShift project or Kubernetes namespace",
      "fstab": "Optional: Specify fstab file on node.  Default is /etc/fstab"
    },
    "_db_comment": "Database file name",
    "db": "/opt/heketi/data/heketi.db",
    "_loglevel_comment": [
      "Set log level. Choices are:",
      "  none, critical, error, warning, info, debug",
      "Default is warning"
    ],
    "loglevel" : "debug"
  }
}

注意：
需要说明的是，heketi有三种executor，分别为mock、ssh、kubernetes，建议在测试环境使用mock，生产环境使用ssh，当glusterfs以容器的方式部署在kubernetes上时，才使用kubernetes。我们这里将glusterfs和heketi独立部署，使用ssh的方式。
使用docker部署的时候，还需将/var/lib/heketi/mounts 挂载至容器里面, heketi 会将此目录作为 gluster volume的挂载点。

systemd配置
cat /usr/lib/systemd/system/heketi.service

[Unit]
Description=RESTful based volume management framework for GlusterFS
Before=network-online.target
After=network-online.target
Documentation=https://github.com/heketi/heketi
[Service]
Type=simple
LimitNOFILE=65536
ExecStart=/opt/heketi/bin/heketi --config=/opt/heketi/conf/heketi.json
KillMode=process
Restart=on-failure
RestartSec=5
SuccessExitStatus=15
StandardOutput=syslog
StandardError=syslog
[Install]
WantedBy=multi-user.target

启动heketi服务
systemctl start heketi
systemctl enable heketi
systemctl status heketi

Heketi管理GlusterFS

添加cluster
/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json cluster create

{"id":"bb1362c3360d80419c822b9994381608","nodes":[],"volumes":[],"block":true,"file":true,"blockvolumes":[]}

将3个glusterfs节点作为node添加到cluster

添加节点

opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json node add --cluster "bb1362c3360d80419c822b9994381608" --management-host-name node108 --storage-host-name 10.14.151.108 --zone 1

{"zone":1,"hostnames":{"manage":["node108"],"storage":["10.14.151.108"]},"cluster":"bb1362c3360d80419c822b9994381608","id":"227fd34c519f0a2c9d5a5b7f3d048745","state":"online","devices":[]}

/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json node add --cluster "bb1362c3360d80419c822b9994381608" --management-host-name node110 --storage-host-name 10.14.151.110 --zone 1

{"zone":1,"hostnames":{"manage":["node110"],"storage":["10.14.151.110"]},"cluster":"bb1362c3360d80419c822b9994381608","id":"5f2d7412f0c874634aa8ee18865533bf","state":"online","devices":[]}

/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json node add --cluster "bb1362c3360d80419c822b9994381608" --management-host-name node145 --storage-host-name 10.14.151.145 --zone 1

{"zone":1,"hostnames":{"manage":["node145"],"storage":["10.14.151.145"]},"cluster":"bb1362c3360d80419c822b9994381608","id":"e20c47a9d9a31a300ed85ccc37441608","state":"online","devices":[]}

查看节点：
/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey node list

Id:227fd34c519f0a2c9d5a5b7f3d048745     Cluster:bb1362c3360d80419c822b9994381608
Id:5f2d7412f0c874634aa8ee18865533bf     Cluster:bb1362c3360d80419c822b9994381608
Id:e20c47a9d9a31a300ed85ccc37441608     Cluster:bb1362c3360d80419c822b9994381608

添加device

机器只是作为gluster的运行单元，volume是基于device创建的。同时需要特别说明的是，目前heketi仅支持使用裸分区或裸磁盘(未格式化)添加为device，不支持文件系统。

/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json device add --name="/dev/sdb" --node "227fd34c519f0a2c9d5a5b7f3d048745"
/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json device add --name="/dev/sdb" --node "5f2d7412f0c874634aa8ee18865533bf"
/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey --json device add --name="/dev/sdb" --node "e20c47a9d9a31a300ed85ccc37441608"

注：--node参数给出的id是上一步创建node时生成的，实际配置中，要添加每一个节点的每一块用于存储的硬盘。

生产实际配置

以上ad-hoc命令均可通过配置文件创建然后导入:

$ sudo cat /data/heketi/conf/topology.json

{
    "clusters": [
        {
            "nodes": [
                {
                    "node": {
                        "hostnames": {
                            "manage": [
                                "k8s1"
                            ],
                            "storage": [
                                "10.111.209.188"
                            ]
                        },
                        "zone": 1
                    },
                    "devices": [
                        "/dev/vdc1"
                    ]
                },
                {
                    "node": {
                        "hostnames": {
                            "manage": [
                                "k8s2"
                            ],
                            "storage": [
                                "10.111.209.189"
                            ]
                        },
                        "zone": 1
                    },
                    "devices": [
                        "/dev/vdc1"
                    ]
                },
                {
                    "node": {
                        "hostnames": {
                            "manage": [
                                "k8s3"
                            ],
                            "storage": [
                                "10.111.209.190"
                            ]
                        },
                        "zone": 1
                    },
                    "devices": [
                        "/dev/vdc1"
                    ]
                }             
            ]
        }
    ]
}

创建:

$ sudo heketi-cli topology load --json topology.json

添加volume

这里仅仅是做一个测试，实际使用中，会由kubernetes自动创建pv.

创建一个大小为3G，副本为2的volume

/opt/heketi/bin/heketi-cli --user admin --server http://10.143.143.111:18080 --secret adminkey volume create --size 3 --replica 2

Name: vol_61055753aa935407b80e1137647733f6

Size: 3

Volume Id: 61055753aa935407b80e1137647733f6

Cluster Id: bb1362c3360d80419c822b9994381608

Mount: 10.14.151.108:vol_61055753aa935407b80e1137647733f6

Mount Options: backup-volfile-servers=10.14.151.110,10.14.151.145

Block: false

Free Size: 0

Reserved Size: 0

Block Hosting Restriction: (none)

Block Volumes: []

Durability Type: replicate

Distribute Count: 1

Replica Count: 2

kubernetes storageclass 配置

创建storageclass

添加storageclass-glusterfs.yaml文件，内容如下：

cat storageclass-glusterfs.yaml

apiVersion: v1

kind: Secret

metadata:

name: heketi-secret

namespace: default

data:

base64 encoded password. E.g.: echo -n "mypassword" | base64

key: YWRtaW5rZXk=

type: kubernetes.io/glusterfs

---

apiVersion: storage.k8s.io/v1beta1

kind: StorageClass

metadata:

name: glusterfs

provisioner: kubernetes.io/glusterfs

allowVolumeExpansion: true

parameters:

resturl: "http://10.143.143.111:18080"

clusterid: "bb1362c3360d80419c822b9994381608"

restauthenabled: "true"

restuser: "admin"

secretNamespace: "default"

secretName: "heketi-secret"

restuserkey: "adminkey"

gidMin: "40000"

gidMax: "50000"

volumetype: "replicate:2"

kubectl apply -f storageclass-glusterfs.yaml

secret/heketi-secret created

storageclass.storage.k8s.io/glusterfs created

kubectl get sc

NAME PROVISIONER AGE

csi-cephfs cephfs.csi.ceph.com 260d

glusterfs kubernetes.io/glusterfs 1m

注意:

storageclass.beta.kubernetes.io/is-default-class: "true" #表示此storageClass作为default sc，创建pvc不指定sc时，默认使用此sc.

reclaimPolicy: Retain #表示pv回收策略为保留，删除pvc时将不删除pv。

更详细的用法参考：<u>https://kubernetes.io/docs/concepts/storage/storage-classes/#glusterfs</u>

创建pvc

kubectl create -f glusterfs-pvc.yaml

cat glusterfs-pvc.yaml

kind: PersistentVolumeClaim

apiVersion: v1

metadata:

name: glusterfs-mysql1

namespace: default

annotations:

volume.beta.kubernetes.io/storage-class: "glusterfs"

spec:

accessModes:

• ReadWriteMany

resources:

requests:

  storage: 1Gi

kubectl create -f glusterfs-pvc.yaml

persistentvolumeclaim/glusterfs-mysql1 created

kubectl get pv

NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE 1y

pvc-5ae5026d-91d2-11ea-bd25-fa157e638e00 1Gi RWX Delete Bound default/glusterfs-mysql1 glusterfs 5m

kubectl get pvc

NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE

glusterfs-mysql1 Bound pvc-5ae5026d-91d2-11ea-bd25-fa157e638e00 1Gi RWX glusterfs 4m

创建pod，使用pvc

cat mysql-deployment.yaml

---

kind: Deployment

apiVersion: extensions/v1beta1

metadata:

name: mysql

namespace: default

spec:

replicas: 1

template:

metadata:

  labels:

    name: mysql

spec:

  containers:

  - name: mysql

    image: mysql:5.7

    imagePullPolicy: IfNotPresent

    env:

    - name: MYSQL_ROOT_PASSWORD

      value: root123456

    ports:

      - containerPort: 3306

    volumeMounts:

    - name: gluster-mysql-data

      mountPath: "/var/lib/mysql"

  volumes:

    - name: gluster-mysql-data

      persistentVolumeClaim:

        claimName: glusterfs-mysql1

kubectl create -f mysql-deployment.yaml

deployment.extensions/mysql created

[# kubectl get deploy

NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE

mysql 1 1 1 1 4m

kubectl get pods

NAME READY STATUS RESTARTS AGE

mysql-b75b5dcfb-cb7qm 1/1 Running 0 5m

]# kubectl exec -ti mysql-b75b5dcfb-cb7qm sh

df -Th

Filesystem Type Size Used Avail Use% Mounted on

overlay overlay 120G 22G 99G 18% /

tmpfs tmpfs 64M 0 64M 0% /dev

tmpfs tmpfs 16G 0 16G 0% /sys/fs/cgroup

/dev/mapper/centos-root xfs 120G 22G 99G 18% /etc/hosts

shm tmpfs 64M 0 64M 0% /dev/shm

10.14.151.108:vol_00de560fab819d81ade9aae98fcdd4d1 fuse.glusterfs 1016M 254M 763M 25% /var/lib/mysql

tmpfs tmpfs 16G 12K 16G 1% /run/secrets/kubernetes.io/serviceaccount

tmpfs tmpfs 16G 0 16G 0% /proc/scsi

tmpfs tmpfs 16G 0 16G 0% /sys/firmware

创建statefulset

---

apiVersion: v1

kind: Service

metadata:

name: nginx

labels:

app: nginx

spec:

ports:

• port: 80

  name: web

clusterIP: None

selector:

app: nginx

---

apiVersion: apps/v1

kind: StatefulSet

metadata:

name: nginx

spec:

selector:

matchLabels:

  app: nginx # has to match .spec.template.metadata.labels

serviceName: "nginx"

replicas: 3 # by default is 1

template:

metadata:

  labels:

    app: nginx # has to match .spec.selector.matchLabels

spec:

  terminationGracePeriodSeconds: 10

  containers:

  - name: nginx

    image: nginx

    ports:

    - containerPort: 80

      name: web

    volumeMounts:

    - name: www

      mountPath: /usr/share/nginx/html

volumeClaimTemplates:

• metadata:

  name: www

  spec:

  accessModes: [ "ReadWriteOnce" ]

  storageClassName: "glusterfs"

  resources:

  requests:
  
    storage: 1Gi
  

kubectl apply -f nginx-statefulset.yml

service/nginx created

statefulset.apps/nginx created

kubectl get pod,pv,pvc

NAME READY STATUS RESTARTS AGE

pod/nginx-0 1/1 Running 0 116s

pod/nginx-1 1/1 Running 0 98s

pod/nginx-2 1/1 Running 0 91s

NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE

persistentvolume/pvc-5ac3eba9-fe12-11e8-a19e-00163e14b18f 1Gi RWO Retain Bound default/www-nginx-0 glusterfs 99s

persistentvolume/pvc-65f27519-fe12-11e8-a19e-00163e14b18f 1Gi RWO Retain Bound default/www-nginx-1 glusterfs 93s

persistentvolume/pvc-69b31512-fe12-11e8-a19e-00163e14b18f 1Gi RWO Retain Bound default/www-nginx-2 glusterfs 86s

NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE

persistentvolumeclaim/www-nginx-0 Bound pvc-5ac3eba9-fe12-11e8-a19e-00163e14b18f 1Gi RWO glusterfs 116s

persistentvolumeclaim/www-nginx-1 Bound pvc-65f27519-fe12-11e8-a19e-00163e14b18f 1Gi RWO glusterfs 98s

persistentvolumeclaim/www-nginx-2 Bound pvc-69b31512-fe12-11e8-a19e-00163e14b18f 1Gi RWO glusterfs 91s

我们可以看到RECLAIM POLICY: Retain ,经过测试

删除pvc，pv status会变成Released状态，且不会被删除

删除pv, 通过heketi-cli volume list查看，volume不会被删除

kubernetes pv和gluster volume不一致时,可使用heketi来统一管理volume.此文档heketi和glusterfs都在kubernetes集群外部署。对于支持AWS EBS的磁盘，可通过EBS storageClass方式将glusterFS heketi部署在容器中管理.参考https://github.com/gluster/gluster-kubernetes

参考文档

https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/

https://kubernetes.io/docs/concepts/storage/storage-classes/#glusterfs

https://github.com/heketi/heketi/blob/master/docs/admin/readme.md

<u>https://www.cnblogs.com/breezey/p/8849466.html</u>

验证测试：

kubectl exec -ti mysql-b75b5dcfb-cb7qm sh

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进容器看挂载的是10.14.151.108的volume，

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关闭10.14.151.108的gluster服务，模拟故障

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进容器后写数据：

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说明挂掉一个节点是不影响用户使用的。

---