测试 Ceph 持久 RBD 设备

laurentbarbe

创建持久 RBD 设备

创建块设备并将其映射到 /etc/ceph/rbdmap

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$ rbd create rbd/myrbd --size=1024
$ echo "rbd/myrbd" >> /etc/ceph/rbdmap
$ service rbdmap reload
[ ok ] Starting RBD Mapping: rbd/myrbd.
[ ok ] Mounting all filesystems...done.

查看 rbd 映射

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$ rbd showmapped
id pool image snap device    
1  rbd  myrbd - /dev/rbd1

创建文件系统并挂载

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$ mkfs.xfs /dev/rbd/rbd/myrbd 
log stripe unit (4194304 bytes) is too large (maximum is 256KiB)
log stripe unit adjusted to 32KiB
meta-data=/dev/rbd/rbd/myrbd     isize=256    agcount=9, agsize=31744 blks
         =                       sectsz=512   attr=2, projid32bit=0
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=1024   swidth=1024 blks
naming   =version 2              bsize=4096   ascii-ci=0
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

$ mkdir -p /mnt/myrbd
$ blkid | grep rbd1
/dev/rbd1: UUID="a07e969e-bb1a-4921-9171-82cf7a737a69" TYPE="xfs"
$ echo "UUID=a07e969e-bb1a-4921-9171-82cf7a737a69 /mnt/myrbd xfs defaults 0 0" >> /etc/fstab
$ mount -a

检查

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$ mount | grep rbd1
/dev/rbd1 on /mnt/myrbd type xfs (rw,relatime,attr2,inode64,sunit=8192,swidth=8192,noquota)

测试快照 

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$ touch /mnt/myrbd/v1

创建快照

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$ sync && xfs_freeze -f /mnt/
$ rbd snap create rbd/myrbd@snap1
$ xfs_freeze -u /mnt/

更改一个文件

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$ mv /mnt/myrbd/v1 /mnt/myrbd/v2

以只读方式挂载快照

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$ mkdir -p /mnt/myrbd@snap1
$ rbd map rbd/myrbd@snap1
$ mount -t xfs -o ro,norecovery,nouuid "/dev/rbd/rbd/myrbd@snap1" "/mnt/myrbd@snap1"
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$ ls "/mnt/myrbd"
total 0
v2

好的。

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$ ls "/mnt/myrbd@snap1"
total 0

什么都没有？？同步出错了？

再试一次

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$ sync && xfs_freeze -f /mnt/
$ rbd snap create rbd/myrbd@snap2
$ xfs_freeze -u /mnt/
$ mkdir -p /mnt/myrbd@snap2
$ rbd map rbd/myrbd@snap2
$ mount -t xfs -o ro,norecovery,nouuid "/dev/rbd/rbd/myrbd@snap2" "/mnt/myrbd@snap2"

再次移动该文件。

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$ mv /mnt/myrbd/v2 /mnt/myrbd/v3
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$ ls /mnt/myrbd@snap2
total 0
v2
$ ls /mnt/myrbd
total 0
v3

好的。

停止 rbdmap（这将删除所有映射的 rbd 设备）

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$ service rbdmap remove

删除 /etc/ceph/rbdmap 中添加的行

删除 myrbd

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$ rbd snap purge rbd/myrbd
Removing all snapshots: 100% complete...done.
$ rbd rm rbd/myrbd
Removing image: 100% complete...done.