lvm 讲解
把磁盘 / dev/sdb 分为三个区, t 可以指定类型, 类型为 LVM(id 为 8e)
设备 Boot Start End Blocks Id System
/dev/sdb1 2048 2099199 1048576 8e Linux LVM
/dev/sdb2 2099200 4196351 1048576 8e Linux LVM
/dev/sdb3 4196352 6293503 1048576 8e Linux LVM
创建物理卷
用 yum provides "/*/pvcreate" 命令查找 lvm 包, yum install -y lvm2 安装
可以用 partprobe 命令生成 / dev/sdb1 文件
使用 pvreate /dev/sdb1 命令分别创建三个物理卷
- [root@aminglinux-02 ~]# pvcreate /dev/sdb1
- WARNING: ext4 signature detected on /dev/sdb1 at offset 1080. Wipe it? [y/n]: y
Wiping ext4 signature on /dev/sdb1.
Physical volume "/dev/sdb1" successfully created.
- [root@aminglinux-02 ~]# pvcreate /dev/sdb2
- Physical volume "/dev/sdb2" successfully created.
- [root@aminglinux-02 ~]# pvcreate /dev/sdb3
- WARNING: dos signature detected on /dev/sdb3 at offset 510. Wipe it? [y/n]: y
Wiping dos signature on /dev/sdb3.
Physical volume "/dev/sdb3" successfully created.
使用 pvdisplay 查看系统中的物理卷
[root@aminglinux-02 ~]# pvdisplay
"/dev/sdb1" is a new physical volume of "1.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sdb1
VG Name
PV Size 1.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID qrwO8j-8kOv-OfEh-bNed-9TcG-5Qyq-scRpyb
"/dev/sdb2" is a new physical volume of "1.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sdb2
VG Name
PV Size 1.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID hPPtFs-Dfmo-zrnZ-mYUA-41Sy-wgfy-Zz0M4P
"/dev/sdb3" is a new physical volume of "1.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sdb3
VG Name
PV Size 1.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID HrV293-eP3T-YJTM-vakP-eKXR-ykLg-xoFq66
pvs 查看物理卷
[root@aminglinux-02 ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sdb1 lvm2 --- 1.00g 1.00g
/dev/sdb2 lvm2 --- 1.00g 1.00g
/dev/sdb3 lvm2 --- 1.00g 1.00g
创建卷组, vgcreate
[root@aminglinux-02 ~]# vgcreate vg1 /dev/sdb1 /dev/sdb2
Volume group "vg1" successfully created
vgdisplay 和 vgs 查看卷组信息
[root@aminglinux-02 ~]# vgdisplay
--- Volume group ---
VG Name vg1
System ID
Format lvm2
Metadata Areas 2
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 2
Act PV 2
VG Size 1.99 GiB
PE Size 4.00 MiB
Total PE 510
Alloc PE / Size 0 / 0
Free PE / Size 510 / 1.99 GiB
VG UUID ufmtbK-zC4s-wsL2-mBEP-HlMy-Vg2Q-dPnkgV
- [root@aminglinux-02 ~]# vgs
- VG #PV #LV #SN Attr VSize VFree
- vg1 2 0 0 wz--n- 1.99g 1.99g
- [root@aminglinux-02 ~]#
vgremove 删除卷组命令
创建逻辑卷, lvcreate -L 100M -n lv1 vg1 从 vg1 里面划分名为 lv1, 大小为 100M 的逻辑卷
[root@aminglinux-02 ~]# lvcreate -L 100M -n lv1 vg1
Logical volume "lv1" created.
格式化, mkfs.ext4 /dev/vg1/lv1
挂载逻辑卷
- [root@aminglinux-02 ~]# mount /dev/vg1/lv1 /mnt/
- [root@aminglinux-02 ~]# df -h
文件系统 容量 已用 可用 已用 % 挂载点
/dev/sda3 28G 1.2G 27G 5% /
devtmpfs 483M 0 483M 0% /dev
tmpfs 493M 0 493M 0% /dev/shm
tmpfs 493M 6.8M 486M 2% /run
tmpfs 493M 0 493M 0% /sys/fs/cgroup
/dev/sda1 197M 109M 88M 56% /boot
tmpfs 99M 0 99M 0% /run/user/0
/dev/mapper/vg1-lv1 93M 1.6M 85M 2% /mnt
扩容逻辑卷
先 umount(xfs 不能卸载)
lvresize -L 200M /dev/vg1/lv1 重新设置卷大小
- [root@aminglinux-02 ~]# lvresize -L 200M /dev/vg1/lv1
- Size of logical volume vg1/lv1 changed from 100.00 MiB (25 extents) to 200.00 MiB (50 extents).
Logical volume vg1/lv1 successfully resized.
e2fsck -f /dev/vg1/lv1 检查磁盘错误 (ext4 执行)
- [root@aminglinux-02 ~]# e2fsck -f /dev/vg1/lv1
- e2fsck 1.42.9 (28-Dec-2013)
第一步: 检查 inode, 块, 和大小
第二步: 检查目录结构
第 3 步: 检查目录连接性
Pass 4: Checking reference counts
第 5 步: 检查簇概要信息
/dev/vg1/lv1: 11/25688 files (9.1% non-contiguous), 8896/102400 blocks
resize2fs /dev/vg1/lv1 更新逻辑卷信息 (ext4 执行)
- root@aminglinux-02 ~]# resize2fs /dev/vg1/lv1
- resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/vg1/lv1 to 204800 (1k) blocks.
The filesystem on /dev/vg1/lv1 is now 204800 blocks long.
xfs_growfs /dev/vg1/lv1 xfs 文件系统需要执行
缩减逻辑卷 (xfs 不支持)
先 umount
e2fsck -f /dev/vg1/lv1 检查磁盘错误 (ext)
resize2fs /dev/vg1/lv1 100M 更新逻辑卷信息 (ext)
lvresize -L 100M /dev/vg1/lv1 重新设置卷大小
扩容卷组
fdisk /dev/sdb 新增 / dev/sdb3(8e)
pvcreate /dev/sdb3 创建物理卷
vgextend vg1 /dev/sdb3 加入卷组
lvresize -L 500M /dev/vg1/lv1 重新设置卷大小
硬盘故障案例
做完 lvm 进不了系统, 由于磁盘挂载错误, 磁盘不能正常挂载到挂载点
输入 root 密码可以进入, 删除错误的挂载点, vim /etc/fstab 删除最后一行
重启
来源: http://www.bubuko.com/infodetail-2559260.html