ceph块存储
ceph块设备，以前称为RADOS块设备，为客户机提供可靠性、分布式和高性能的块存储磁盘。RADOS块设备利用librbd库并以顺序的形式在ceph集群的多个osd上存储数据块。RBD是由ceph的RADOS层支持，因此每个块设备都分布在多个ceph节点上，提供了性能和优异的可靠性。RBD有linux内核的本地支持，这意味着RBD驱动程序从过去几年就与linux内核集成的很好。除了可靠性和性能外，RBD还提供了企业特性，例如完整和增量快照、瘦配置、写时复制克隆、动态调整大小等，RBD还支持内存缓存，这大大提高了性能。
安装ceph块存储客户端
创建ceph块客户端用户名和认证密钥
[ceph-admin@ceph-node1 my-cluster]$ ceph auth get-or-create client.rbd mon 'allow r' osd 'allow class-read object_prefix rbd_children, allow rwx pool=rbd' | tee ./ceph.client.rbd.keyring [client.rbd] key = AQChG2Vcu552KRAAMf4/SdfSVa4sFDZPfsY8bg== [ceph-admin@ceph-node1 my-cluster]$ ceph auth get client.rbd exported keyring for client.rbd [client.rbd] key = AQChG2Vcu552KRAAMf4/SdfSVa4sFDZPfsY8bg== caps mon = "allow r" caps osd = "allow class-read object_prefix rbd_children, allow rwx pool=rbd"
将密钥文件和配置文件拷贝到客户端
[ceph-admin@ceph-node1 my-cluster]$ scp ceph.client.rbd.keyring /etc/ceph/ceph.conf root@192.168.0.123:/etc/ceph
检查客户端是否符合块设备环境要求
[root@localhost ~]# uname -r
3.10.0-862.el7.x86_64
[root@localhost ~]# modprobe rbd
[root@localhost ~]# echo $?
0
安装ceph客户端
[root@localhost ~]# wget -O /etc/yum.repos.d/ceph.repo https://raw.githubusercontent.com/aishangwei/ceph-demo/master/ceph-deploy/ceph.repo [root@localhost ~]# yum install -y ceph
测试密钥连接集群
[root@localhost ~]# ceph -s --name client.rbd cluster: id: cde2c9f7-009e-4bb4-a206-95afa4c43495 health: HEALTH_OK services: mon: 3 daemons, quorum ceph-node1,ceph-node2,ceph-node3 mgr: ceph-node1(active), standbys: ceph-node2, ceph-node3 osd: 9 osds: 9 up, 9 in data: pools: 0 pools, 0 pgs objects: 0 objects, 0B usage: 9.06GiB used, 171GiB / 180GiB avail pgs:
客户端创建块设备及映射
创建rbd池
[ceph-admin@ceph-node1 my-cluster]$ ceph osd lspools [ceph-admin@ceph-node1 my-cluster]$ ceph osd pool create rbd 128 pool 'rbd' created [ceph-admin@ceph-node1 my-cluster]$ ceph osd lspools 1 rbd,
客户端创建块设备
[root@localhost ceph]# rbd create rbd1 --size 10240 --name client.rbd
查看
[root@localhost ceph]# rbd ls -p rbd --name client.rbd rbd1 [root@localhost ceph]# rbd list --name client.rbd rbd1 [root@localhost ceph]# rbd --image rbd1 info --name client.rbd rbd image 'rbd1': size 10GiB in 2560 objects order 22 (4MiB objects) block_name_prefix: rbd_data.faa76b8b4567 format: 2 features: layering, exclusive-lock, object-map, fast-diff, deep-flatten flags: create_timestamp: Thu Feb 14 17:53:54 2019
映射到客户端
[root@localhost ceph]# rbd map --image rbd1 --name client.rbd rbd: sysfs write failed RBD image feature set mismatch. You can disable features unsupported by the kernel with "rbd feature disable rbd1 object-map fast-diff deep-flatten". In some cases useful info is found in syslog - try "dmesg | tail". rbd: map failed: (6) No such device or address
映射报错
layering：分层支持
exclusive-lock：排它锁定支持对
object-map：对象映射支持，需要排它所（exclusive-lock）。
deep-flatten：快照平支持（snapshot flatten support）
fast-diff：在client-node1上使用krbd（内核rbd）客户机进行快速diff计算（需要对象映射），我们将无法在centos内核3.10上映射块设备映像，因为该内核不支持对象映射（object-map）、深平（deep-flatten）和快速diff（fast-diff）（在内核4.9中引入了支持）。为了解决这个问题，我们将禁用不支持的特性，有几个选项可以做到这一点：
1）动态禁用
[root@localhost ceph]# rbd feature disable rbd1 exclusive-lock object-map fast-diff deep-flatten --name client.rbd
2）创建rbd镜像时之启用分层特性
[root@localhost ceph]# rbd create rbd2 --size 10240 --image-feature layering --name client.rbd
3）ceph配置文件中禁用
rbd default features = 1
再次映射到客户端
[root@localhost ceph]# rbd map --image rbd1 --name client.rbd /dev/rbd0 [root@localhost ceph]# rbd showmapped --name client.rbd id pool image snap device 0 rbd rbd1 - /dev/rbd0
创建文件系统，并挂载
[root@localhost ceph]# fdisk -l /dev/rbd0 Disk /dev/rbd0: 10.7 GB, 10737418240 bytes, 20971520 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 4194304 bytes / 4194304 bytes [root@localhost ceph]# mkfs.xfs /dev/rbd0 meta-data=/dev/rbd0 isize=512 agcount=16, agsize=163840 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=2621440, imaxpct=25 = sunit=1024 swidth=1024 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=2560, version=2 = sectsz=512 sunit=8 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 [root@localhost ceph]# mkdir /mnt/ceph-disk1 [root@localhost ceph]# mount /dev/rbd0 /mnt/ceph-disk1 [root@localhost ceph]# df -h /mnt/ceph-disk1 Filesystem Size Used Avail Use% Mounted on /dev/rbd0 10G 33M 10G 1% /mnt/ceph-disk1
写入数据测试
[root@localhost ceph]# ll /mnt/ceph-disk1/ total 0 [root@localhost ceph]# dd if=/dev/zero of=/mnt/ceph-disk1/file1 count=100 bs=1M 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 0.127818 s, 820 MB/s [root@localhost ceph]# ll /mnt/ceph-disk1/ total 102400 -rw-r--r-- 1 root root 104857600 Feb 15 10:47 file1 [root@localhost ceph]# df -h /mnt/ceph-disk1/ Filesystem Size Used Avail Use% Mounted on /dev/rbd0 10G 133M 9.9G 2% /mnt/ceph-disk1
开机自动挂载
下载脚本
[root@localhost ceph]# wget -O /usr/local/bin/rbd-mount https://raw.githubusercontent.com/aishangwei/ceph-demo/master/client/rbd-mount [root@localhost ceph]# chmod +x /usr/local/bin/rbd-mount [root@localhost ceph]# cat /usr/local/bin/rbd-mount #!/bin/bash # Pool name where block device image is stored export poolname=rbd # Disk image name export rbdimage=rbd1 # Mounted Directory export mountpoint=/mnt/ceph-disk1 # Image mount/unmount and pool are passed from the systemd service as arguments # Are we are mounting or unmounting if [ "$1" == "m" ]; then modprobe rbd rbd feature disable $rbdimage object-map fast-diff deep-flatten rbd map $rbdimage --id rbd --keyring /etc/ceph/ceph.client.rbd.keyring mkdir -p $mountpoint mount /dev/rbd/$poolname/$rbdimage $mountpoint fi if [ "$1" == "u" ]; then umount $mountpoint rbd unmap /dev/rbd/$poolname/$rbdimage fi
做成系统服务
[root@localhost ceph]# wget -O /etc/systemd/system/rbd-mount.service https://raw.githubusercontent.com/aishangwei/ceph-demo/master/client/rbd-mount.service [root@localhost ceph]# systemctl daemon-reload [root@localhost ceph]# systemctl enable rbd-mount.service
重启查看自动挂载
[root@localhost ceph]# reboot -f [root@localhost ceph]# df -h /mnt/ceph-disk1/ Filesystem Size Used Avail Use% Mounted on /dev/rbd1 10G 133M 9.9G 2% /mnt/ceph-disk1 [root@localhost ceph]# ll -h /mnt/ceph-disk1/ total 100M -rw-r--r-- 1 root root 100M Feb 15 10:47 file1