我在 LVM LV 之上的 LUKS 之上有一个 500GiB 的 ext4 文件系统。我想将 LV 的大小调整为 100GiB。我知道如何在 LVM LV 之上调整 ext4 的大小,但我该如何处理 LUKS 卷?
mgorven@moab:~% sudo lvdisplay /dev/moab/backup
--- Logical volume ---
LV Name /dev/moab/backup
VG Name moab
LV UUID nQ3z1J-Pemd-uTEB-fazN-yEux-nOxP-QQair5
LV Write Access read/write
LV Status available
# open 1
LV Size 500.00 GiB
Current LE 128000
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 2048
Block device 252:3
mgorven@moab:~% sudo cryptsetup status backup
/dev/mapper/backup is active and is in use.
type: LUKS1
cipher: aes-cbc-essiv:sha256
keysize: 256 bits
device: /dev/mapper/moab-backup
offset: 3072 sectors
size: 1048572928 sectors
mode: read/write
mgorven@moab:~% sudo tune2fs -l /dev/mapper/backup
tune2fs 1.42 (29-Nov-2011)
Filesystem volume name: backup
Last mounted on: /srv/backup
Filesystem UUID: 63877e0e-0549-4c73-8535-b7a81eb363ed
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Filesystem features: has_journal ext_attr resize_inode dir_index filetype extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize
Filesystem flags: signed_directory_hash
Default mount options: (none)
Filesystem state: clean with errors
Errors behavior: Continue
Filesystem OS type: Linux
Inode count: 32768000
Block count: 131071616
Reserved block count: 0
Free blocks: 112894078
Free inodes: 32044830
First block: 0
Block size: 4096
Fragment size: 4096
Reserved GDT blocks: 992
Blocks per group: 32768
Fragments per group: 32768
Inodes per group: 8192
Inode blocks per group: 512
RAID stride: 128
RAID stripe width: 128
Flex block group size: 16
Filesystem created: Sun Mar 11 19:24:53 2012
Last mount time: Sat May 19 13:29:27 2012
Last write time: Fri Jun 1 11:07:22 2012
Mount count: 0
Maximum mount count: 100
Last checked: Fri Jun 1 11:03:50 2012
Check interval: 31104000 (12 months)
Next check after: Mon May 27 11:03:50 2013
Lifetime writes: 118 GB
Reserved blocks uid: 0 (user root)
Reserved blocks gid: 0 (group root)
First inode: 11
Inode size: 256
Required extra isize: 28
Desired extra isize: 28
Journal inode: 8
Default directory hash: half_md4
Directory Hash Seed: 383bcbc5-fde9-4720-b98e-2d6224713ecf
Journal backup: inode blocks
LUKS 实际上并不存储设备的大小——它只是在打开卷时发现它。因此,只有在该过程中没有关闭并重新打开卷(例如进行在线增长)时,它才会发挥作用。在这种情况下,需要重新发现打开卷的大小。
要缩小音量,请使用以下过程:
umount
resize2fs
cryptsetup luksClose
lvreduce
使用或调整 LV 的大小lvresize
cryptsetup luksOpen
mount
也可以省略
luksClose
和luksOpen
步骤,cryptsetup resize
调整 LV 大小后使用。还要记住,LUKS 使用一些额外的空间来存储元数据,因此 LV 需要比文件系统稍大一些。我通常将文件系统的大小调整得非常小,然后在调整 LV 大小后再次增大它。如果您正在增长文件系统并想在线进行,您将使用以下过程:
lvextend
使用或调整 LV 的大小lvresize
cryptsetup resize
resize2fs