GlusterFS是一个可扩展，分布式文件系统，集成来自多台服务器上的磁盘存储资源到单一全局命名空间，以提供共享文件存储。
特点：
GFS存储的一些术语：
GFS卷（volume）的模式：
Volume是一组Brick的组合，一个gfs集群中可以有多个volume，可以供客户端挂载、存储数据等，它有很多种模式供选择：
| 主机名 | ip地址 | 角色 |
|---|---|---|
| master | 192.168.72.100 | k8s-master、glusterfs、heketi |
| node1 | 192.168.72.101 | k8s-work节点 |
| node2 | 192.168.72.102 | k8s-work节点 |
获取gluster rpm包，我这里是7.5版本的，需要下载以下几个rpm包：
# lsglusterfs-7.5-1.el7.x86_64.rpm glusterfs-libs-7.5-1.el7.x86_64.rpmglusterfs-api-7.5-1.el7.x86_64.rpm glusterfs-server-7.5-1.el7.x86_64.rpmglusterfs-api-devel-7.5-1.el7.x86_64.rpm psmisc-22.20-15.el7.x86_64.rpmglusterfs-cli-7.5-1.el7.x86_64.rpm userspace-rcu-0.10.0-3.el7.x86_64.rpmglusterfs-client-xlators-7.5-1.el7.x86_64.rpm userspace-rcu-0.7.16-1.el7.x86_64.rpmglusterfs-fuse-7.5-1.el7.x86_64.rpm地址：https://buildlogs.centos.org/centos/7/storage/x86_64/gluster-9/Packages/；如果有外网可以直接配置yum源安装需要的版本。
安装rpm包
## 先安装依赖的环境包yum -y install attr psmisc rpcbind## 安装glusterfsrpm -ivh glusterfs-libs-7.5-1.el7.x86_64.rpm rpm -ivh glusterfs-7.5-1.el7.x86_64.rpmrpm -ivh glusterfs-api-7.5-1.el7.x86_64.rpm glusterfs-cli-7.5-1.el7.x86_64.rpm glusterfs-client-xlators-7.5-1.el7.x86_64.rpmrpm -ivh glusterfs-fuse-7.5-1.el7.x86_64.rpmrpm -ivh userspace-rcu-0.10.0-3.el7.x86_64.rpmrpm -ivh glusterfs-server-7.5-1.el7.x86_64.rpmrpm -ivh glusterfs-api-devel-7.5-1.el7.x86_64.rpm因为包之间会有依赖关系，按照以上顺序可以顺利安装，如果不想这么麻烦，可强制安装--force --nodeps。
启动服务
## 需要启动两个服务glusterd和glusterfsdsystemctl start glusterd glusterfsdglusterd和glusterfsd两个服务的区别，以及gluster和glusterfs命令
glusterd是其服务的守护进程，是一个管理模块，处理gluster发过来的命令，处理集群管理、存储池管理、brick管理、负载均衡、快照管理等，默认端口24007：
# ss -tnlp | grep 24007LISTEN 0 128 *:24007 *:* users:(("glusterd",pid=7873,fd=10))## 进程# ps -ef | grep glusterroot 7873 1 0 Mar28 ? 00:00:41 /usr/sbin/glusterd -p /var/run/glusterd.pid --log-level INFOglusterfsd是服务端模块，存储池中的每个brick（卷组）都会启动一个glusterfsd进程。此模块主要是处理客户端的读写请求，默认端口是从49152开始，后续端口都+1。我这里启动了两个卷组：
# ss -tnlp | grep glusterLISTEN 0 128 *:49152 *:* users:(("glusterfsd",pid=7898,fd=11))LISTEN 0 128 *:49153 *:* users:(("glusterfsd",pid=44275,fd=11))## 进程# ps -ef | grep glusterroot 7898 1 0 Mar28 ? 00:04:46 /usr/sbin/glusterfsd -s 192.168.72.100 --volfile-id xtest-fs.192.168.72.100.data-text-mind -p /var/run/gluster/vols/xtest-fs/192.168.72.100-data-text-mind.pid -S /var/run/gluster/3b5c03678c749dfd.socket --brick-name /data/text-mind -l /var/log/glusterfs/bricks/data-text-mind.log --xlator-option *-posix.glusterd-uuid=46bfd5ab-07be-4a97-993f-1ddab13e0ee9 --process-name brick --brick-port 49152 --xlator-option xtest-fs-server.listen-port=49152glusterfs命令是一个客户端模块，负责通过mount挂载集群中某台服务器的存储池，以目录的形式呈现给用户。用户mount几个卷组，就是出现几个glusterfs的进程，如下：
# ps -ef | grep -w glusterfs | grep -v glusterfsdroot 31496 1 0 Mar25 ? 00:02:46 /usr/sbin/glusterfs --process-name fuse --volfile-server=yq01-aip-aikefu10.yq01.baidu.com --volfile-id=xtest-fs /data/mntgluster命令就是客户端请求命令，负责发起请求，比如创建、查看当前卷组等：
# gluster volume create xtest-fs 192.168.72.100:/data/xtest-fs/brick force# gluster volume list 如果是多台gfs构成集群，在服务安装完毕之后，要进行一个添加的动作
## 添加# gluster peer probe node1# gluster peer probe node2## 查看当前集群# gluster pool listheketi提供一个RESTful管理节点界面，可以用来管理GlusterFS卷的生命周期，通过heketi，就可以像使用Opentack Manila，kubernete和openShift一样申请可以动态配置GlusterFS卷，Heketi会动态在集群内选择bricks构建所需的volumes，这样以确保数据的副本会分散到集群不同的故障域内。
安装heketi服务，有源可以直接yum安装，没有可以单独下载rpm包安装，或者通过docker、k8s安装
# yum -y install heketi heketi-client# heketi --version Heketi 9.0.0# systemctl start heketi.service配置ssh秘钥，使heketi节点可以免密访问glusterfs节点
# ssh-keygen -f /etc/heketi/heketi_key -t rsa -N ''# ssh-copy-id -i /etc/heketi/heketi_key.pub master# chown heketi:heketi /etc/heketi/编辑heketi的配置文件/etc/heketi/heketi.json
heketi有三种执行方式，分别为mock，ssh，kubernetes，官方建议在测试和开发环境使用mock，生产使用ssh，如果glusterfs是部署在k8s上，则使用kubernetes方式。
下边对配置部分做出解释：
{ ## heketi服务的默认端口，可以更改。 "_port_comment": "Heketi Server Port Number", "port": "8080", ## 是否开启认证，一般选是。 "_use_auth": "Enable JWT authorization. Please enable for deployment", "use_auth": true, ## 若开启认证，则需要编辑认证的用户及密码。 "_jwt": "Private keys for access", "jwt": { "_admin": "Admin has access to all APIs", "admin": { "key": "My Secret" }, "_user": "User only has access to /volumes endpoint", "user": { "key": "My Secret" } }, "_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." ], ## 选择操作gfs的方式，这里选择ssh。 "executor": "ssh", ## 配置ssh秘钥 "_sshexec_comment": "SSH username and private key file information", "sshexec": { "keyfile": "/etc/heketi/heketi_key", "user": "root", "port": "22", "fstab": "/etc/fstab" }, ## 配置k8s证书 "_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", ## heketi的数据存储位置 "db": "/var/lib/heketi/heketi.db", "_loglevel_comment": [ "Set log level. Choices are:", " none, critical, error, warning, info, debug", "Default is warning" ], ## heketi的日志级别 "loglevel" : "debug" }}启动heketi服务，设置开启自启，测试访问
# systemctl start heketi# systemctl enable heketi# curl http://master:8080/helloHello from Heketi配置heketi连接gfs服务
(1) 在集群的主节点设置环境变量，注意端口根据实际情况修改
# export HEKETI_CLI_SERVER=http://master:8080(2) 在集群的主节点修改/usr/share/heketi/topology-sample.json配置文件，执行添加节点和添加device的操作：
{ "clusters": [ { "nodes": [ { "node": { "hostnames": { "manage": [ "master" ], "storage": [ "192.168.72.100" ] }, "zone": 1 }, "devices": [ { "name": "/dev/sdb", "destroydata": false } ] } ] } ]}manage指定gfs主机域名，storage指定gfs主机ip，devices下指定要存储gfs数据的数据盘，此盘应该是一块未分区的干净盘，分区应该也可以，我这里没有试。
可以添加多个主机和多块盘，具体格式如下：
{ "clusters": [ { "nodes": [ { "node": { "hostnames": { "manage": [ "192.168.10.100" ], "storage": [ "192.168.10.100" ] }, "zone": 1 }, "devices": [ { "name": "/dev/sdb", "destroydata": false }, { "name": "/dev/sdc", "destroydata": false }, { "name": "/dev/sdd", "destroydata": false }, { "name": "/dev/sde", "destroydata": false }, { "name": "/dev/sdf", "destroydata": false }, { "name": "/dev/sdg", "destroydata": false }, { "name": "/dev/sdh", "destroydata": false }, { "name": "/dev/sdi", "destroydata": false } ] }, { "node": { "hostnames": { "manage": [ "192.168.10.101" ], "storage": [ "192.168.10.101" ] }, "zone": 2 }, "devices": [ { "name": "/dev/sdb", "destroydata": false }, { "name": "/dev/sdc", "destroydata": false }, { "name": "/dev/sdd", "destroydata": false }, { "name": "/dev/sde", "destroydata": false }, { "name": "/dev/sdf", "destroydata": false }, { "name": "/dev/sdg", "destroydata": false }, { "name": "/dev/sdh", "destroydata": false }, { "name": "/dev/sdi", "destroydata": false } ] }, { "node": { "hostnames": { "manage": [ "192.168.10.102" ], "storage": [ "192.168.10.102" ] }, "zone": 1 }, "devices": [ { "name": "/dev/sdb", "destroydata": false }, { "name": "/dev/sdc", "destroydata": false }, { "name": "/dev/sdd", "destroydata": false }, { "name": "/dev/sde", "destroydata": false }, { "name": "/dev/sdf", "destroydata": false }, { "name": "/dev/sdg", "destroydata": false }, { "name": "/dev/sdh", "destroydata": false }, { "name": "/dev/sdi", "destroydata": false } ] }, { "node": { "hostnames": { "manage": [ "192.168.10.103" ], "storage": [ "192.168.10.103" ] }, "zone": 2 }, "devices": [ { "name": "/dev/sdb", "destroydata": false }, { "name": "/dev/sdc", "destroydata": false }, { "name": "/dev/sdd", "destroydata": false }, { "name": "/dev/sde", "destroydata": false }, { "name": "/dev/sdf", "destroydata": false }, { "name": "/dev/sdg", "destroydata": false }, { "name": "/dev/sdh", "destroydata": false }, { "name": "/dev/sdi", "destroydata": false } ] } ] } ]}(3) 导入配置文件到heketi，使heketi管理gfs
# heketi-cli -s $HEKETI_CLI_SERVER --user admin --secret 'My Secret' topology load --json=/usr/share/heketi/topology-sample.jsonCreating cluster ... ID: 6b7b8affdb10add55ea367e7e2f8e091 Allowing file volumes on cluster. Allowing block volumes on cluster. Creating node master ... ID: 96bbfbf66bc8ad551fe5a8c8ef289218 Adding device /dev/sdb ... OK如果报错：Error: Unable to get topology information: Invalid JWT token: Token missing iss claim。是因为没加用户名和密码 --user admin --secret 'My Secret'。
(4) 测试创建一个volume，看是否成功
# heketi-cli volume create --size=10 --durability=none --user "admin" --secret "My Secret"Name: vol_38412746b79cf0d7ffa69a3969c1cfedSize: 10Volume Id: 38412746b79cf0d7ffa69a3969c1cfedCluster Id: 6b7b8affdb10add55ea367e7e2f8e091Mount: 192.168.72.100:vol_38412746b79cf0d7ffa69a3969c1cfedMount Options: backup-volfile-servers=Block: falseFree Size: 0Reserved Size: 0Block Hosting Restriction: (none)Block Volumes: []Durability Type: noneDistribute Count: 1创建成功，heketi已经可以管理gfs服务。
创建StorageClass
vi storageclass-gfs-heketi-distributed.yaml
apiVersion: storage.k8s.io/v1kind: StorageClassmetadata: name: gluster-distributedprovisioner: kubernetes.io/glusterfsreclaimPolicy: Retainparameters: resturl: "http://192.168.72.100:8080" restauthenabled: "true" restuser: "admin" restuserkey: "My Secret" gidMin: "40000" gidMax: "50000" volumetype: "none"allowVolumeExpansion: truevolumeBindingMode: Immediateprovisioner：表示存储分配器，需要根据后端存储的不同而变更；
reclaimPolicy: 默认即“Delete”，删除pvc后，相应的pv及后端的volume，brick(lvm)等一起删除；设置为”Retain”时则保留数据，需要手工处理
resturl：heketi API服务提供的url；
restauthenabled：可选参数，默认值为"false"，heketi服务开启认证时必须设置为"true"；
restuser：可选参数，开启认证时设置相应用户名；
restuserkey：可选参数。开启认证时输入对应用户的密码；
secretNamespace：可选参数，开启认证时可以设置为使用持久化存储的namespace；
secretName：可选参数，开启认证时，需要将heketi服务的认证密码保存在secret资源中；
clusterid：可选参数，指定集群id，也可以是1个clusterid列表，格式为"id1,id2"；
volumetype：可选参数，设置卷类型及其参数，如果未分配卷类型，则有分配器决定卷类型；如"volumetype: replicate:3"表示3副本的replicate卷，"volumetype: disperse:4:2"表示disperse卷，其中‘4’是数据，’2’是冗余校验，"volumetype: none"表示distribute卷；
allowVolumeExpansion：表示是否支持动态扩容，默认为true；
volumeBindingMode：表示是否立即bound pv，可选值WaitForFirstConsumer和Immediate；
创建sc：
# kubectl create -f storageclass-gfs-heketi-distributed.yaml# kubectl get sc NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSIONgluster-distributed kubernetes.io/glusterfs Retain Immediate true 创建pvc
vi glusterfs-pvc.yaml
apiVersion: v1kind: PersistentVolumeClaimmetadata: name: glusterfs-testspec: accessModes: - ReadWriteMany resources: requests: storage: 5Gi storageClassName: gluster-distributed创建pvc
# kubectl create -f glusterfs-pvc.yaml# kubectl get pvc NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGEglusterfs-test Bound pvc-0a3cffea-36b0-4609-a983-88df995b99e8 5Gi RWX gluster-distributed 5s这个时候 df -h 就可以看到有新的分区被挂载
# df -h | tail -n 1 /dev/mapper/vg_5b4ef948902b85845afd387ca71c6858-brick_0fd0afa344ca798d7a9fccab5bb60a9e 5.0G 33M 5.0G 1% /var/lib/heketi/mounts/vg_5b4ef948902b85845afd387ca71c6858/brick_0fd0afa344ca798d7a9fccab5bb60a9e创建一个deployment，测试读写
vi glusterfs-deploy.yaml
apiVersion: apps/v1kind: Deploymentmetadata: name: glusterfs-deploy labels: app: nginxspec: replicas: 2 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: registry:5000/nginx:1.13 imagePullPolicy: IfNotPresent ports: - name: web containerPort: 80 volumeMounts: - name: pvc-glusterfs mountPath: /data volumes: - name: pvc-glusterfs persistentVolumeClaim: claimName: glusterfs-test创建deployment
# kubectl create -f glusterfs-deploy.yaml deployment.apps/glusterfs-deploy created# kubectl get pod | grep glusglusterfs-deploy-cfd8c8578-45r9z 1/1 Running 0 72sglusterfs-deploy-cfd8c8578-vjrzn 1/1 Running 0 104s测试读写
# kubectl exec -it glusterfs-deploy-cfd8c8578-45r9z -- bash# cd /data/# for i in `seq 1 10`; do echo $i > $i ; done # ls1 10 2 3 4 5 6 7 8 9# cat 1 1至此，gfs已经可以作为k8s的storageclass来动态管理pv pvc了。