CentOS7下配置GlusterFS供Kubernetes使用

[TOC]

1. 环境说明

系统：CentOS7，/data为非系统分区挂载目录
docker：1.13.1
kubernetes：1.11.1
glusterfs：4.1.2

2. GlusterFS部署

2个节点，192.168.105.97、192.168.105.98

使用yum安装

yum install centos-release-glusteryum -y install glusterfs glusterfs-fuse glusterfs-server

CentOS-Gluster-4.1.repo

启动及设置开机启动

systemctl start glusterd systemctl enable glusterd

GlusterFS通过24007端口相互通信。防火墙需要开放端口。

/etc/hosts

127.0.0.1 ??localhost localhost.localdomain localhost4 localhost4.localdomain4::1 ????????localhost localhost.localdomain localhost6 localhost6.localdomain6# k8s 192.168.105.92 lab1 ?# master1192.168.105.93 lab2 ?# master2192.168.105.94 lab3 ?# master3192.168.105.95 lab4 ?# node4192.168.105.96 lab5 ?# node5# glusterfs192.168.105.98 glu1 ?# glusterfs1192.168.105.97 harbor1 ?# harbor1

在主机glu1上执行

#添加节点到集群执行操作的本机不需要probe本机gluster peer probe harbor1

查看集群状态（节点间相互看到对方信息）

gluster peer status

Number of Peers: 1Hostname: harbor1Uuid: ebedc57b-7c71-4ecb-b92e-a7529b2fee31State: Peer in Cluster (Connected)

GlusterFS 几种volume模式说明： ???
链接中比较直观：https://docs.gluster.org/en/latest/Administrator%20Guide/Setting%20Up%20Volumes/ ???

1. 默认模式，既DHT, 也叫分布卷: 将文件已hash算法随机分布到 一台服务器节点中存储。 ???
   命令格式：gluster volume create test-volume server1:/exp1 server2:/exp2 ???
2. 复制模式，既AFR, 创建volume 时带 replica x 数量: 将文件复制到 replica x 个节点中，现在已经推荐3节点仲裁者复制模式，因为2节点可能产生脑裂。
   命令格式：gluster volume create test-volume replica 2 transport tcp server1:/exp1 server2:/exp2 ???
   gluster volume create test-volume replica 3 arbiter 1 transport tcp server1:/exp1 server2:/exp2 server3:/exp3 ?????
3. 分布式复制模式，至少4节点。
   命令格式：gluster volume create test-volume replica 2 transport tcp server1:/exp1 server2:/exp2 server3:/exp3 server4:/exp4 ???
4. 分散模式，最少需要3节点 ???
   命令格式：gluster volume create test-volume disperse 3 server{1..3}:/bricks/test-volume ???
5. 分布式分散模式，创建一个分布式分散体积,分散关键字和<数量>是强制性的，指定的砖块在命令行中的数量必须是分散数的倍数 ???
   命令格式：gluster volume create <volname> disperse 3 server1:/brick{1..6} ???

gluster volume create k8s_volume 192.168.105.98:/data/glusterfs/dev/k8s_volumegluster volume start k8s_volumegluster volume statusgluster volume info

列一些Glusterfs调优：

# 开启 指定 volume 的配额gluster volume quota k8s-volume enable# 限制 指定 volume 的配额gluster volume quota k8s-volume limit-usage / 1TB# 设置 cache 大小, 默认32MBgluster volume set k8s-volume performance.cache-size 4GB# 设置 io 线程, 太大会导致进程崩溃gluster volume set k8s-volume performance.io-thread-count 16# 设置 网络检测时间, 默认42sgluster volume set k8s-volume network.ping-timeout 10# 设置 写缓冲区的大小, 默认1Mgluster volume set k8s-volume performance.write-behind-window-size 1024MB

3. 客户端使用GlusterFS

###3.1 物理机上使用GlusterFS的volume

yum install -y centos-release-glusteryum install -y glusterfs glusterfs-fuse fuse fuse-libs openib libibverbsmkdir -p /tmp/testmount -t glusterfs 192.168.105.98:k8s_volume/tmp/test ?# 和NFS挂载用法类似

3.2 Kubernetes使用GlusterFS

以下操作在kubernetes master节点操作

3.2.1 创建GlusterFS端点定义

vim /etc/kubernetes/glusterfs/glusterfs-endpoints.json

{ ?"kind": "Endpoints", ?"apiVersion": "v1", ?"metadata": { ???"name": "glusterfs-cluster" ?}, ?"subsets": [ ???{ ?????"addresses": [ ???????{ ?????????"ip": "192.168.105.98" ???????} ?????], ?????"ports": [ ???????{ ?????????"port": 1 ???????} ?????] ???}, ???{ ?????"addresses": [ ???????{ ?????????"ip": "192.168.105.97" ???????} ?????], ?????"ports": [ ???????{ ?????????"port": 1 ???????} ?????] ???} ?]}

注意：
该subsets字段应填充GlusterFS集群中节点的地址。可以在port字段中提供任何有效值（从1到65535）。

kubectl apply -f /etc/kubernetes/glusterfs/glusterfs-endpoints.jsonkubectl get endpoints

NAME ???????????????ENDPOINTS ????????????????????????????????????????????????????AGEglusterfs-cluster ??192.168.105.97:1,192.168.105.98:1 ?

3.2.2 配置 service

我们还需要为这些端点创建服务，以便它们能够持久存在。我们将在没有选择器的情况下添加此服务，以告知Kubernetes我们想要手动添加其端点

vim glusterfs-service.json

{ ?"kind": "Service", ?"apiVersion": "v1", ?"metadata": { ???"name": "glusterfs-cluster" ?}, ?"spec": { ???"ports": [ ?????{"port": 1} ???] ?}}

kubectl apply -f glusterfs-service.json 

3.3.3 配置PersistentVolume

创建glusterfs-pv.yaml文件，指定storage容量和读写属性

vim glusterfs-pv.yaml

apiVersion: v1kind: PersistentVolumemetadata: ?name: pv001spec: ?capacity: ???storage: 10Gi ?accessModes: ???- ReadWriteMany ?glusterfs: ???endpoints: "glusterfs-cluster" ???path: "k8s_volume" ???readOnly: false

kubectl apply -f glusterfs-pv.yaml kubectl get pv

NAME ?????CAPACITY ??ACCESS MODES ??RECLAIM POLICY ??STATUS ?????CLAIM ????STORAGECLASS ??REASON ???AGEpv001 ????10Gi ??????RWX ???????????Retain ??????????Available ?????????????????????????????????????21s

3.3.4 配置PersistentVolumeClaim

创建glusterfs-pvc.yaml文件，指定请求资源大小

vim glusterfs-pvc.yaml

apiVersion: v1kind: PersistentVolumemetadata: ?name: pv001spec: ?capacity: ???storage: 10Gi ?accessModes: ???- ReadWriteMany ?glusterfs: ???endpoints: "glusterfs-cluster" ???path: "k8s_volume" ???readOnly: false

kubectl apply -f glusterfs-pvc.yamlkubectl get pvc

NAME ?????STATUS ???VOLUME ???CAPACITY ??ACCESS MODES ??STORAGECLASS ??AGEpvc001 ???Bound ????zk001 ????10Gi ??????RWX ??????????????????????????44s

3.3.5 部署应用挂载pvc

以创建nginx，把pvc挂载到容器内的/usr/share/nginx/html文件夹为例：

vim glusterfs-nginx-deployment.yaml

apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2kind: Deploymentmetadata: ?name: nginx-dm ?namespace: defaultspec: ?selector: ???matchLabels: ?????app: nginx ?replicas: 2 # tells deployment to run 2 pods matching the template ?template: ???metadata: ?????labels: ???????app: nginx ???spec: ?????containers: ?????- name: nginx ???????image: nginx ???????ports: ?????????- containerPort: 80 ???????volumeMounts: ?????????- name: storage001 ???????????mountPath: "/usr/share/nginx/html" ?????volumes: ???????- name: storage001 ?????????persistentVolumeClaim: ???????????claimName: pvc001

kubectl create -f nginx_deployment.yaml# 查看部署是否成功kubectl get pod|grep nginx-dm

nginx-dm-c8c895d96-hfdsz ???????????1/1 ??????Running ??0 ?????????36snginx-dm-c8c895d96-jrfbx ???????????1/1 ??????Running ??0 ?????????36s

验证结果：

# 查看挂载[root@lab1 glusterfs]# kubectl exec -it nginx-dm-c8c895d96-5h649 -- df -h|grep nginx192.168.105.97:k8s_volume 1000G ??11G ?990G ??2% /usr/share/nginx/html[root@lab1 glusterfs]# kubectl exec -it nginx-dm-c8c895d96-zf6ch -- df -h|grep nginx192.168.105.97:k8s_volume 1000G ??11G ?990G ??2% /usr/share/nginx/html[root@lab1 glusterfs]# kubectl exec -it nginx-dm-c8c895d96-5h649 -- touch /usr/share/nginx/html/ygqygq2 ?????[root@lab1 glusterfs]# kubectl exec -it nginx-dm-c8c895d96-5h649 -- ls -lt /usr/share/nginx/html/total 1-rw-r--r--. 1 root root 4 Aug 13 09:43 ygqygq2-rw-r--r--. 1 root root 5 Aug 13 09:34 ygqygq2.txt[root@lab1 glusterfs]# kubectl exec -it nginx-dm-c8c895d96-zf6ch -- ls -lt /usr/share/nginx/html/total 1-rw-r--r--. 1 root root 4 Aug 13 09:43 ygqygq2-rw-r--r--. 1 root root 5 Aug 13 09:34 ygqygq2.txt

至此部署完成。

4. 小结

此文GlusterFS是安装在物理系统下，而非kubernetes中，所有需要手工维护，下次介绍在kubernetes中安装使用gluster。GlusterFS的volume模式根据业务灵活应用。需要注意的是，如果使用分布卷，pod中的挂载目录文件可能存在卷的任一节点中，可能并非直接df -h看到的那个节点中。

参数资料：
[1] https://kubernetes.io/docs/concepts/storage/persistent-volumes/
[2] https://kubernetes.io/docs/tasks/configure-pod-container/configure-persistent-volume-storage/
[3] https://www.kubernetes.org.cn/4069.html
[4] https://www.gluster.org/
[5] https://blog.csdn.net/hxpjava1/article/details/79817078
[6] https://docs.gluster.org/en/latest/Administrator%20Guide/Setting%20Up%20Volumes/
[7] https://docs.gluster.org/en/latest/Administrator%20Guide/Setting%20Up%20Clients/
[8] https://github.com/kubernetes/examples/blob/master/staging/volumes/glusterfs/README.md

CentOS7下配置GlusterFS供Kubernetes使用

原文地址：http://blog.51cto.com/ygqygq2/2160958