lvm磁盤掛載方法
系統環境：centos 7.x ubuntu
一.fdisk -l 查看分區信息，找到要添加的硬盤盤符 如：/dev/vdb
#fdisk -l
Disk /dev/vdb: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes二.劃分物理分區
（一）分區沒超過2T的,使用fdisk
（1）fdisk /dev/vdb
#fdisk /dev/vdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xd069b076.
Command (m for help): （2） n(新建)、p-1、其他的默認
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-104857599, default 2048): #輸入開始分區位置，回車默認位置
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-104857599, default 104857599): #輸入結束分區位置，回車默認全部分區
Using default value 104857599
Partition 1 of type Linux and of size 50 GiB is set（3）將磁盤格式修改爲lvm格式， t(改格式)、8e
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'（4）p 查看創建分區信息，w 保存
Command (m for help): p
Disk /dev/vdb: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xd069b076
Device Boot Start End Blocks Id System
/dev/vdb1 2048 104857599 52427776 8e Linux LVM
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
# partprobe ##更新分區表（二）分區超過2T的,用parted
（1）parted /dev/vdb
#parted /dev/vdb
GNU Parted 3.1
Using /dev/vdb
Welcome to GNU Parted! Type 'help' to view a list of commands.（2）mklabel gpt #設置格式爲gpt
(parted) p
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
(parted) mklabel gpt
Warning: The existing disk label on /dev/vdb will be destroyed and all data on this disk will be lost. Do you want to
continue?
Yes/No? yes
(parted) p
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
（3）mkpart #新建分區
(parted) mkpart
Partition name? []? vdb1 #分區名稱
File system type? [ext2]? ext4 #文件系統類型
Start? 1 #起始位置，1爲1M，一般預留1M空間
End? 100% #結束位置，100% 爲使用全部空間
(parted) p #顯示分區內容
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
1 1049kB 53.7GB 53.7GB vdb1
(parted) q #退出
Information: You may need to update /etc/fstab.三.將創建的vdb1分區，創建pv 物理卷
#pvcreate /dev/vdb1
Physical volume "/dev/vdb1" successfully created.
#pvdisplay
--- Physical volume ---
PV Name /dev/vda2
VG Name centos
PV Size <99.00 GiB / not usable 3.00 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 25343
Free PE 1
Allocated PE 25342
PV UUID 2I5XOD-VzbD-fCZU-gdTm-fLPD-pnpa-oUjYjg
"/dev/vdb1" is a new physical volume of "<50.00 GiB"
--- NEW Physical volume ---
PV Name /dev/vdb1
VG Name
PV Size <50.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID u1CAKQ-Tae9-0XwY-Y9Vs-Ub9G-rlL9-r6VXIz四.創建vg卷組，創建lv邏輯卷
（一）擴展已有分區
（1）vgdisplay #查看要擴展的vg（卷組）的名稱 例如：centos
#vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 4
Open LV 4
Max PV 0
Cur PV 1
Act PV 1
VG Size <99.00 GiB
PE Size 4.00 MiB
Total PE 25343
Alloc PE / Size 25342 / 98.99 GiB
Free PE / Size 1 / 4.00 MiB
VG UUID QHEpYY-Z6c1-dAkv-9Vl5-uWs7-Ydpa-OQNNvF（2）vgextend centos /dev/vdb1 #把vdb1的pv空間擴展給centos的vg
#vgextend centos /dev/vdb1
Volume group "centos" successfully extended
#vgdisplay #查看增加後的卷組
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 6
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 4
Open LV 4
Max PV 0
Cur PV 2
Act PV 2
VG Size 148.99 GiB
PE Size 4.00 MiB
Total PE 38142
Alloc PE / Size 25342 / 98.99 GiB
Free PE / Size 12800 / 50.00 GiB
VG UUID QHEpYY-Z6c1-dAkv-9Vl5-uWs7-Ydpa-OQNNvF（3）df -hT #查看要增加空間的名稱，例要增加根目錄 / 的空間
#df -hT
Filesystem Type Size Used Avail Use% Mounted on
devtmpfs devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs tmpfs 5.8G 0 5.8G 0% /dev/shm
tmpfs tmpfs 5.8G 27M 5.8G 1% /run
tmpfs tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/mapper/centos-root xfs 50G 8.6G 42G 18% /
/dev/vda1 xfs 1014M 209M 806M 21% /boot
/dev/mapper/centos-home xfs 31G 33M 31G 1% /home
/dev/mapper/centos-var_log xfs 12G 65M 11G 1% /var/log
tmpfs tmpfs 1.6G 0 1.6G 0% /run/user/0（4）lvextend -l +100%FREE /dev/mapper/centos-root #將空閒的空間，都增 加給lv（邏輯卷），即增加給根目錄 /
#lvextend -l +100%FREE /dev/mapper/centos-root
Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to 100.00 GiB (25600 extents).
Logical volume centos/root successfully resized.
（5）xfs_growfs /dev/mapper/centos-root #重新刷新識別空間(注：xfs_growfs命令,針對的是xfs文件系統，resize2fs命令 針對的是ext2、ext3、ext4文件系統)
#xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=3276800 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=13107200, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=6400, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 13107200 to 26214400（6）df -hT #查看確認空間增長
#df -hT
Filesystem Type Size Used Avail Use% Mounted on
devtmpfs devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs tmpfs 5.8G 0 5.8G 0% /dev/shm
tmpfs tmpfs 5.8G 27M 5.8G 1% /run
tmpfs tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/mapper/centos-root xfs 100G 8.6G 92G 9% /
/dev/vda1 xfs 1014M 209M 806M 21% /boot
/dev/mapper/centos-home xfs 31G 33M 31G 1% /home
/dev/mapper/centos-var_log xfs 12G 66M 11G 1% /var/log
tmpfs tmpfs 1.6G 0 1.6G 0% /run/user/0（二）掛載新的分區
（1）vgcreate myvg /dev/vdb1 #創建新的vg 卷組
（2）lvcreate -l +100%FREE myvg -n mylv #-L 100G 是隻分100G給lv
（3）mkfs.ext4 /dev/myvg/mylv #格式化lv
（4）分別用pvdisplay、vgdisplay、lvdisplay查看添加的pv、vg、lv
（5）mkdir /data #新建要掛載的文件夾
（6）vi /etc/fstab ,在末尾添加 /dev/myvg/mylv /data ext4 defaults 0 0
（7）mount -a #掛載成功
（8）df -hT #查看掛載的分區和空間
五.xfs文件系統空間減小方法（如果分區有數據，不能減小）
（一）umount /home #卸載分區
（二）減少home分區空間
# lvreduce -L -100G /dev/mapper/centos-home
WARNING: Reducing active logical volume to 618.00 GiB.
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce centos/home? [y/n]: y
Size of logical volume centos/home changed from 718.00 GiB (183808 extents) to 618.00 GiB (158208 extents).
Logical volume centos/home successfully resized.
（三）xfs文件系統不能直接執行分區減小的調整
# xfs_growfs /dev/mapper/centos-home
xfs_growfs: /dev/mapper/centos-home is not a mounted XFS filesystem
# mount /dev/mapper/centos-home /home/
mount: /dev/mapper/centos-home：不能讀超級塊
（四）重新格式化這個分區，格式化後才能再次掛載到home下
# mkfs.xfs /dev/mapper/centos-home -f
meta-data=/dev/mapper/centos-home isize=512 agcount=4, agsize=41156608 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=164626432, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=80384, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
# mount /dev/mapper/centos-home /home/
（五）df -hT查看，空間已經減小100G了，但/home裏的文件已經被 格式化，丟失了。
# df -hT
文件系統 類型 容量 已用 可用 已用% 掛載點
/dev/mapper/centos-root xfs 205G 2.2G 203G 2% /
devtmpfs devtmpfs 32G 0 32G 0% /dev
tmpfs tmpfs 32G 0 32G 0% /dev/shm
tmpfs tmpfs 32G 49M 32G 1% /run
tmpfs tmpfs 32G 0 32G 0% /sys/fs/cgroup
/dev/sda1 xfs 197M 139M 59M 71% /boot
tmpfs tmpfs 6.3G 0 6.3G 0% /run/user/0
/dev/mapper/centos-home xfs 618G 73M 578G 1% /home
# vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 9
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 3
Open LV 3
Max PV 0
Cur PV 1
Act PV 1
VG Size 930.80 GiB
PE Size 4.00 MiB
Total PE 238285
Alloc PE / Size 211456 / 826.00 GiB
Free PE / Size 26829 / 104.80 GiB
VG UUID a5hiAh-LB8M-9lRv-Ps1a-z35L-J4fk-sP3KrF
注：格式化時，也可以格式化成ext4格式的，增加減少空間就比較方便，不會存在要格式化分區的情況
# mkfs.ext4 /dev/mapper/centos-home #格式化成ext4格式
#lvextend -L 120G /dev/mapper/centos-home #增大至120G
lvreduce -L -80G /dev/mapper/centos-home #減小80G
resize2fs /dev/mapper/centos-home #執行調整