ceph的image扩容

root@ceph01:/etc/ceph# rbd create --size 1024 test
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# rbd ls
mysql-hzb
test
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# rbd info
rbd: image name was not specified
root@ceph01:/etc/ceph# rbd info test
rbd image 'test':
    size 1024 MB in 256 objects
    order 22 (4096 kB objects)
    block_name_prefix: rbd_data.10ac74b0dc51
    format: 2
    features: layering
    flags:
root@ceph01:/etc/ceph# rbd map test
/dev/rbd0
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# mkdir -p /root/testrbd/
root@ceph01:/etc/ceph# mkfs.xfs -q /dev/rbd0
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# rbd showmapped
id pool image snap device
0  rbd  test  -    /dev/rbd0
root@ceph01:/etc/ceph# mount /dev/rbd0 /root/testrbd/
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# df -h /root/testrbd/
文件系统        容量  已用  可用 已用% 挂载点
/dev/rbd0      1014M   33M  982M    4% /root/testrbd
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# rbd resize --size 2048 test
Resizing image: 100% complete...done.
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# df -h /root/testrbd/
文件系统        容量  已用  可用 已用% 挂载点
/dev/rbd0      1014M   33M  982M    4% /root/testrbd
root@ceph01:/etc/ceph# rbd map test
/dev/rbd1
root@ceph01:/etc/ceph# df -h /root/testrbd/
文件系统        容量  已用  可用 已用% 挂载点
/dev/rbd0      1014M   33M  982M    4% /root/testrbd
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph#
root@ceph01:/etc/ceph# 

由以上可以看出：虽然image已经增大了两倍，但是挂载此image的文件系统/dev/rbd0/的大小并没有变

要想/dev/rbd0也增大，则要做下面操作，ext4和xfs格式的方法不一样

1）ext4

resize2fs /dev/rbd0

2）xfs

要在 resize之后执行

# xfs_growfs /root/testrbd/