004.Ceph块设备基础使用

一 基础准备

• 参考《002.ceph安装部署》文档部署一个基础集群；
• 新增节点主机名及ip在deploy节点添加解析：

  1 [root@deploy ~]# echo "172.24.8.75 cephclient" >>/etc/hosts

• 配置国内yum源：

  1 [root@cephclient ~]# yum -y update
  2 [root@cephclient ~]# rm /etc/yum.repos.d/* -rf
  3 [root@cephclient ~]# wget -o /etc/yum.repos.d/centos-base.repo http://mirrors.aliyun.com/repo/centos-7.repo
  4 [root@cephclient ~]# yum -y install epel-release
  5 [root@cephclient ~]# mv /etc/yum.repos.d/epel.repo /etc/yum.repos.d/epel.repo.backup
  6 [root@cephclient ~]# mv /etc/yum.repos.d/epel-testing.repo /etc/yum.repos.d/epel-testing.repo.backup
  7 [root@cephclient ~]# wget -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

 

二 块设备

2.1 添加普通用户

  1 [root@cephclient ~]# useradd -d /home/cephuser -m cephuser
  2 [root@cephclient ~]# echo "cephuser" | passwd --stdin cephuser	#cephclient节点创建cephuser用户
  3 [root@cephclient ~]# echo "cephuser all = (root) nopasswd:all" > /etc/sudoers.d/cephuser
  4 [root@cephclient ~]# chmod 0440 /etc/sudoers.d/cephuser
  5 [root@deploy ~]# su - manager
  6 [manager@deploy ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub cephuser@172.24.8.75

 

2.2 安装ceph-client

  1 [root@deploy ~]# su - manager
  2 [manager@deploy ~]$ cd my-cluster/
  3 [manager@deploy my-cluster]$ vi ~/.ssh/config
  4 host node1
  5    hostname node1
  6    user cephuser
  7 host node2
  8    hostname node2
  9    user cephuser
 10 host node3
 11    hostname node3
 12    user cephuser
 13 host cephclient
 14    hostname cephclient						#新增cephclient节点信息
 15    user cephuser
 16 [manager@deploy my-cluster]$ ceph-deploy install cephclient	#安装ceph

 

注意：若使用ceph-deploy部署的时候出现安装包无法下载，可在部署时候指定ceph.repo为国内源：

  1 ceph-deploy install cephclient --repo-url=https://mirrors.aliyun.com/ceph/rpm-mimic/el7/ --gpg-url=https://mirrors.aliyun.com/ceph/keys/release.asc

  1 [manager@deploy my-cluster]$ ceph-deploy admin cephclient

提示：为方便后期deploy节点管理cephclient，在cli中使用命令中简化相关key的输出，可将key复制至相应节点。ceph-deploy 工具会把密钥环复制到/etc/ceph目录，要确保此密钥环文件有读权限（如 sudo chmod +r /etc/ceph/ceph.client.admin.keyring ）。

2.3 创建pool

  1 [manager@deploy my-cluster]$ ssh node1 sudo ceph osd pool create mytestpool 64

2.4 初始化pool

  1 [root@cephclient ~]# ceph osd lspools
  2 [root@cephclient ~]# rbd pool init mytestpool

 

2.5 创建块设备

  1 [root@cephclient ~]# rbd create mytestpool/mytestimages --size 4096 --image-feature layering

2.6 确认验证

  1 [root@cephclient ~]# rbd ls mytestpool
  2 mytestimages
  3 [root@cephclient ~]# rbd showmapped
  4 id pool       image        snap device
  5 0  mytestpool mytestimages -    /dev/rbd0
  6 [root@cephclient ~]# rbd info mytestpool/mytestimages

 

2.7 将image映射为块设备

  1 [root@cephclient ~]# rbd map mytestpool/mytestimages --name client.admin
  2 /dev/rbd0

 

2.8 格式化设备

  1 [root@cephclient ~]# mkfs.ext4 /dev/rbd/mytestpool/mytestimages
  2 [root@cephclient ~]# lsblk

 

2.9 挂载并测试

  1 [root@cephclient ~]# sudo mkdir /mnt/ceph-block-device
  2 [root@cephclient ~]# sudo mount /dev/rbd/mytestpool/mytestimages /mnt/ceph-block-device/
  3 [root@cephclient ~]# cd /mnt/ceph-block-device/
  4 [root@cephclient ceph-block-device]# echo 'this is my test file!' >> test.txt
  5 [root@cephclient ceph-block-device]# ls
  6 lost+found  test.txt

 

2.10 自动map

  1 [root@cephclient ~]# vim /etc/ceph/rbdmap
  2 # rbddevice     parameters
  3 #poolname/imagename id=client,keyring=/etc/ceph/ceph.client.keyring
  4 mytestpool/mytestimages id=admin,keyring=/etc/ceph/ceph.client.admin.keyring

 

2.11 开机挂载

  1 [root@cephclient ~]# vi /etc/fstab
  2 #……
  3 /dev/rbd/mytestpool/mytestimages    /mnt/ceph-block-device  ext4    defaults,noatime,_netdev    0 0

 

2.12 rbdmap开机启动

  1 [root@cephclient ~]# systemctl enable rbdmap.service
  2 [root@cephclient ~]# df -ht				#查看验证

 

提示：若出现开机后依旧无法自动挂载，rbdmap也异常，可如下操作：

  1 [root@cephclient ~]# vi /usr/lib/systemd/system/rbdmap.service
  2 [unit]
  3 description=map rbd devices
  4 wantedby=multi-user.target			#需要新增此行
  5 #……