centos6 使用raid5构建lvm逻辑卷
1、将之前实验环境还原：
a、利用umount先卸载之前挂载的文件系统；
b、修改/etc/fstab里面的数据，让开机不会自动挂载；
c、利用fdisk将该分区删除；
整合raid5和lvm实验
实验环境：
一块6G的盘，分成5个分区，每个分区1G。
其中4个作为active态，一个为spare态。
fdisk -l
开始磁盘分区：
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000[root@srcxtts ~]# fdisk /dev/sdd
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0x95cc4770.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-783, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-783, default 783): +1G
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (133-783, default 133):
Using default value 133
Last cylinder, +cylinders or +size{K,M,G} (133-783, default 783): +1G
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 3
First cylinder (265-783, default 265):
Using default value 265
Last cylinder, +cylinders or +size{K,M,G} (265-783, default 783): +1G
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
/dev/sdd3 265 396 1060290 83 Linux
Command (m for help): n
Command action
e extended
p primary partition (1-4)
e
Selected partition 4
First cylinder (397-783, default 397):
Using default value 397
Last cylinder, +cylinders or +size{K,M,G} (397-783, default 783):
Using default value 783
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
/dev/sdd3 265 396 1060290 83 Linux
/dev/sdd4 397 783 3108577+ 5 Extended
Command (m for help): n
First cylinder (397-783, default 397):
Using default value 397
Last cylinder, +cylinders or +size{K,M,G} (397-783, default 783): +1G
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
/dev/sdd3 265 396 1060290 83 Linux
/dev/sdd4 397 783 3108577+ 5 Extended
/dev/sdd5 397 528 1060258+ 83 Linux
Command (m for help): n
First cylinder (529-783, default 529):
Using default value 529
Last cylinder, +cylinders or +size{K,M,G} (529-783, default 783): +1G
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
/dev/sdd3 265 396 1060290 83 Linux
/dev/sdd4 397 783 3108577+ 5 Extended
/dev/sdd5 397 528 1060258+ 83 Linux
/dev/sdd6 529 660 1060258+ 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.2、创建raid5磁盘
[root@srcxtts ~]# mdadm --create --auto=yes /dev/md0 --level=5 \
> --raid-devices=4 --spare-devices=1 /dev/sdd{1,2,3,5,6}
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
[root@srcxtts ~]# ll /dev/md0
brw-rw----. 1 root disk 9, 0 5月 10 09:26 /dev/md0
[root@srcxtts ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdd5[5] sdd6[4](S) sdd3[2] sdd2[1] sdd1[0]
3176448 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
unused devices: 3、对raid5磁盘/dev/md0创建pv
[root@srcxtts ~]# pvcreate /dev/md0
Physical volume "/dev/md0" successfully created
[root@srcxtts ~]# pvdisplay /dev/md0
"/dev/md0" is a new physical volume of "3.03 GiB"
--- NEW Physical volume ---
PV Name /dev/md0
VG Name
PV Size 3.03 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID GjGVBh-z3h6-uyD0-xNjQ-LflN-j1gb-XvR4I74、根据生成的pv创建vg，参数默认，pe大小默认4M
[root@srcxtts ~]# vgcreate raidvg /dev/md0
Volume group "raidvg" successfully created[root@srcxtts ~]# vgdisplay raidvg
--- Volume group ---
VG Name raidvg
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 1
Act PV 1
VG Size 3.03 GiB
PE Size 4.00 MiB
Total PE 775
Alloc PE / Size 0 / 0
Free PE / Size 775 / 3.03 GiB
VG UUID Jx2ZNz-juP4-g8fx-oPJ5-F3Mg-QYn4-WoZ5HO5、把vg中全部的pe都分配给lv，创建lv
[root@srcxtts ~]# lvcreate -l 775 -n raidlv raidvg
Logical volume "raidlv" created
[root@srcxtts ~]# lvscan
ACTIVE '/dev/vg_srcxtts/lv_root' [21.58 GiB] inherit
ACTIVE '/dev/vg_srcxtts/lv_swap' [3.94 GiB] inherit
ACTIVE '/dev/raidvg/raidlv' [3.03 GiB] inherit
[root@srcxtts ~]# lvdisplay /dev/raidvg/raidlv
--- Logical volume ---
LV Path /dev/raidvg/raidlv
LV Name raidlv
VG Name raidvg
LV UUID rOaylO-3Br7-sUo3-3IRZ-Rf4D-O5V8-A98KGh
LV Write Access read/write
LV Creation host, time srcxtts, 2018-05-10 09:29:36 +0800
LV Status available
# open 0
LV Size 3.03 GiB
Current LE 775
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 6144
Block device 253:26、将lv格式化为ext3文件系统
[root@srcxtts ~]# mkfs.ext3 /dev/raidvg/raidlv
mke2fs 1.41.12 (17-May-2010)
文件系统标签=
操作系统:Linux
块大小=4096 (log=2)
分块大小=4096 (log=2)
Stride=128 blocks, Stripe width=384 blocks
198400 inodes, 793600 blocks
39680 blocks (5.00%) reserved for the super user
第一个数据块=0
Maximum filesystem blocks=813694976
25 block groups
32768 blocks per group, 32768 fragments per group
7936 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912
正在写入inode表: 完成
Creating journal (16384 blocks): 完成
Writing superblocks and filesystem accounting information: 完成
This filesystem will be automatically checked every 33 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.7、创建挂载点并挂载lv
[root@srcxtts ~]# mkdir /mnt/raidlvm
[root@srcxtts ~]# mount /dev/raidvg/raidlv /mnt/raidlvm[root@srcxtts ~]# df -h
文件系统 容量 已用 可用 已用%% 挂载点
/dev/mapper/vg_srcxtts-lv_root
22G 11G 9.4G 54% /
tmpfs 2.0G 84K 2.0G 1% /dev/shm
/dev/sda1 477M 60M 392M 14% /boot
/dev/mapper/raidvg-raidlv
3.0G 69M 2.8G 3% /mnt/raidlvm
[root@srcxtts ~]# 到此整合就完成了。
实验还原：
1、卸载lv文件系统
[root@srcxtts ~]# umount /mnt/raidlvm
[root@srcxtts ~]# df -h
文件系统 容量 已用 可用 已用%% 挂载点
/dev/mapper/vg_srcxtts-lv_root
22G 11G 9.4G 54% /
tmpfs 2.0G 84K 2.0G 1% /dev/shm
/dev/sda1 477M 60M 392M 14% /boot2、移除lv
[root@srcxtts ~]# lvremove /dev/raidvg/raidlv
Do you really want to remove active logical volume raidlv? [y/n]: y
Logical volume "raidlv" successfully removed3、改变vg的状态为非active
[root@srcxtts ~]# vgchange -an raidvg
0 logical volume(s) in volume group "raidvg" now active4、移除vg
[root@srcxtts ~]# vgremove raidvg
Volume group "raidvg" successfully removed5、移除pv
[root@srcxtts ~]# pvremove /dev/md0
Labels on physical volume "/dev/md0" successfully wiped6、停md0 raid磁盘
[root@srcxtts ~]# mdadm --stop /dev/md0
mdadm: stopped /dev/md07、使用fdisk将磁盘还原
[root@srcxtts ~]# fdisk /dev/sdd
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): p
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
/dev/sdd1 1 132 1060258+ 83 Linux
/dev/sdd2 133 264 1060290 83 Linux
/dev/sdd3 265 396 1060290 83 Linux
/dev/sdd4 397 783 3108577+ 5 Extended
/dev/sdd5 397 528 1060258+ 83 Linux
/dev/sdd6 529 660 1060258+ 83 Linux
Command (m for help): d
Partition number (1-6): 1
Command (m for help): d
Partition number (1-6): 2
Command (m for help): d
Partition number (1-6): 3
Command (m for help): d
Partition number (1-6): 4
Command (m for help): d
No partition is defined yet!
Command (m for help): 5
5: unknown command
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition's system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality (experts only)
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@srcxtts ~]# fdisk /dev/sdd
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): q
[root@srcxtts ~]# fdisk /dev/sdd -l
Disk /dev/sdd: 6442 MB, 6442450944 bytes
255 heads, 63 sectors/track, 783 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x95cc4770
Device Boot Start End Blocks Id System
[root@srcxtts ~]#