测试数据
cd / && dd if=/dev/zero of=file bs=1M count=10000
将磁盘变大的测试命令. 生产环境不要用. 这只是用于测试扩容后的效果
LVM基础命令:
pvdisplay 查看检查pv
pvremove /dev/sdb #清除一个pv
vgremove [vg名] #清除一个vg
lvremove [lv名] #清除一个lv
fdisk -l 检查磁盘
df -h 检查全部磁盘大小
df -Th 检查磁盘大小和分区格式类型
pvdisplay 检查pv
vgdisplay 检查vg
lvdisplay 检查lv
0. 添加磁盘后需要进行扫描识别
echo "- - -" > /sys/class/scsi_host/host0/scan
echo "- - -" > /sys/class/scsi_host/host1/scan
echo "- - -" > /sys/class/scsi_host/host2/scan
1. 检查当前磁盘
[root@localhost /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 40G 9.6G 31G 24% /
devtmpfs 982M 0 982M 0% /dev
tmpfs 993M 0 993M 0% /dev/shm
tmpfs 993M 8.7M 984M 1% /run
tmpfs 993M 0 993M 0% /sys/fs/cgroup
/dev/sda1 197M 103M 95M 53% /boot
tmpfs 199M 0 199M 0% /run/user/0
注意: /dev/mapper/centos-root 是逻辑卷的路径.
2. 检查pv [ pvdisplay ]
[root@localhost /]# pvdisplay
--- Physical volume ---
PV Name /dev/sda2
VG Name centos
PV Size 19.80 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 5069
Free PE 0
Allocated PE 5069
PV UUID 4YLVja-jT6q-FphK-3E60-5Qde-Z3gw-zLpcYT
--- Physical volume ---
PV Name /dev/sdb1
VG Name centos
PV Size <20.00 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 5119
Free PE 0
Allocated PE 5119
PV UUID SBfuCJ-tli0-Mi2U-wO3w-eQub-0v36-0XkQBw
3. 检查vg
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 1
Act PV 1
VG Size 19.80 GiB
PE Size 4.00 MiB
Total PE 5069
Alloc PE / Size 5069 / 19.80 GiB
Free PE / Size 0 / 0
VG UUID lkJhAi-7Df5-0K69-LYV4-exS2-ZqE1-FYMyIG
4. 检查lv
[root@localhost ~]# lvdisplay
--- Logical volume ---
LV Path /dev/centos/root
LV Name root
VG Name centos
LV UUID tUUfhM-dDfU-Aw6K-tiAj-wyqf-cvbl-FcLOxj
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2019-11-22 04:12:42 +0800
LV Status available
# open 1
LV Size 19.80 GiB
Current LE 5069
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
扩容思路
1. 加入磁盘
2. 检查磁盘id 修改成需要扩容的磁盘ID一致,通过fdisk -l 可以查看ID
[root@localhost ~]# fdisk -l /dev/sda
.....
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 411647 204800 83 Linux
/dev/sda2 411648 41943039 20765696 8e Linux LVM
可以看到ID是 8e LVM,所以新加入的磁盘也需要改为 8e
3. 创建物理卷 pv
4. pv加入vg卷组
5. 扩容磁盘
6. 格式化磁盘
7. 结束
扩容磁盘
1. 添加磁盘
xxx 自己意淫把
2. 扫描新增磁盘
扫描:
echo "- - -" > /sys/class/scsi_host/host0/scan
echo "- - -" > /sys/class/scsi_host/host1/scan
echo "- - -" > /sys/class/scsi_host/host2/scan
3. 分区更改磁盘格式为LVM:
## 创建分区并修改磁盘格式为 [8e]:
fdisk /dev/sdc [操作新磁盘]
[root@localhost /]# fdisk /dev/sdc
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 0xc7dec5f2.
Command (m for help): n #####-----创建分区
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p):
Using default response p #####-----创建默认主分区[主分区总共就只能分出4个超过4个需要创建扩展分区]
Partition number (1-4, default 1):
First sector (2048-62914559, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-62914559, default 62914559):
Using default value 62914559
Partition 1 of type Linux and of size 30 GiB is set
Command (m for help): t #####-----更改磁盘格式
Selected partition 1
Hex code (type L to list all codes): 8e #####-----更改为8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): p ### 查看一下是不是 8e
Disk /dev/sdc: 32.2 GB, 32212254720 bytes, 62914560 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: 0xc7dec5f2
Device Boot Start End Blocks Id System
/dev/sdc1 2048 62914559 31456256 8e Linux LVM #确实已经是8e了
Command (m for help): w #####-----保存
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
##分区和磁盘格式更改完毕
4. 创建物理卷组:
# 创建物理卷 pvcreate /dev/sdc1
[root@localhost /]# pvcreate /dev/sdc1
Physical volume "/dev/sdc1" successfully created.
# 物理卷加入刀 centos 这个 vg 中
[root@localhost /]# vgextend centos /dev/sdc1
Volume group "centos" successfully extended
5. 检查PE个数
vgdisplay
[root@localhost /]# vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 3
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 3
Act PV 3
VG Size 69.79 GiB
PE Size 4.00 MiB
Total PE 17867
Alloc PE / Size 10188 / <39.80 GiB
Free PE / Size 7679 / <30.00 GiB ###这是剩余PE数量, 7679,也是新增的30G磁盘,7679个PE
VG UUID lkJhAi-7Df5-0K69-LYV4-exS2-ZqE1-FYMyIG
6. 扩容磁盘:
#先看目前磁盘情况:
[root@localhost /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 40G 9.6G 31G 24% / ## 31G.
devtmpfs 982M 0 982M 0% /dev
tmpfs 993M 0 993M 0% /dev/shm
tmpfs 993M 8.7M 984M 1% /run
tmpfs 993M 0 993M 0% /sys/fs/cgroup
/dev/sda1 197M 103M 95M 53% /boot
tmpfs 199M 0 199M 0% /run/user/0
# 扩容并格式化磁盘:
lvresize -r -l +7679 /dev/centos/root
#结果:
[root@localhost /]# lvresize -r -l +7679 /dev/centos/root
Size of logical volume centos/root changed from <39.80 GiB (10188 extents) to 69.79 GiB (17867 extents).
Logical volume centos/root successfully resized.
meta-data=/dev/mapper/centos-root isize=512 agcount=9, agsize=1297664 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=10432512, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 10432512 to 18295808
#这是将所有PE都划分给了 /dev/centos/root , 其中 -r 是划分的同时格式化这块新磁盘,并加入到 该分区中.
#也就是自己先格式化后扩容给/dev/centos/root 磁盘 .
#这种方法是按照PE个数来划分磁盘的, 磁盘总大小就是 磁盘总大小 = PE个数 * PE size
7. 检查磁盘现有情况:
# 查看现有磁盘大小:
[root@localhost /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 70G 9.6G 61G 14% / ##-----扩容成功,磁盘从 32%下降到了14 ,大小也变成了 61G
devtmpfs 982M 0 982M 0% /dev
tmpfs 993M 0 993M 0% /dev/shm
tmpfs 993M 8.7M 984M 1% /run
tmpfs 993M 0 993M 0% /sys/fs/cgroup
/dev/sda1 197M 103M 95M 53% /boot
tmpfs 199M 0 199M 0% /run/user/0
## 31G+扩容给的 30G一共是 61G 全部划分正确.
查看磁盘UUID:
[root@localhost ~]# blkid
/dev/sda1: UUID="cb322c86-f37a-49e8-86a0-924d9b0c719e" TYPE="xfs"
/dev/sda2: UUID="4YLVja-jT6q-FphK-3E60-5Qde-Z3gw-zLpcYT" TYPE="LVM2_member"
/dev/sdb1: UUID="SBfuCJ-tli0-Mi2U-wO3w-eQub-0v36-0XkQBw" TYPE="LVM2_member"
/dev/sdc1: UUID="Z7K8RO-denr-cyn8-sCjb-9HMa-Pu3I-ciK3kt" TYPE="LVM2_member"
/dev/sr0: UUID="2017-09-06-10-51-00-00" LABEL="CentOS 7 x86_64" TYPE="iso9660" PTTYPE="dos"
/dev/mapper/centos-root: UUID="e3508edd-30c0-4e7d-9d8f-622c8dbd174e" TYPE="xfs"
扩容完成.