Centos 7.4 服務器配置LVM(邏輯卷管理)
本章Blog相關知識點:
LVM是 Logical Volume Manager(邏輯卷管理)的簡寫,它是Linux環境下對磁盤分區進行管理的一種機制,LVM是建立在硬盤和 分區之上的一個邏輯層,來提高磁盤分區管理的靈活性。LVM將若幹個磁盤分區連接為一個整塊的卷組 (volumegroup),形成一個存儲池。管理員可以在卷組上隨意創建邏輯卷組(logicalvolumes),並進一步在邏輯卷組上創建文件系 統。
與傳統的磁盤與分區相比,LVM為計算機提供了更高層次的磁盤存儲。它使系統管理員可以更方便的為應用與用戶分配存儲空間。在LVM管理下的存儲卷可以按需要隨時改變大小與移除(可能需對文件系統工具進行升級)。 LVM是在磁盤分區和文件系統之間添加的一個邏輯層,來為文件系統屏蔽下層磁盤分區布局,提供一個抽象的盤卷,在盤卷上建立文件系統。
邏輯卷管理概念:
物理卷(physical volume)——物理卷就是指硬盤分區或從邏輯上與磁盤分區具有同樣功能的設備(如RAID),是LVM的基本存儲邏輯塊。但和基本的物理存儲介質(如分區,磁盤等)比較, 卻包含有與LVM相關的管理參數。
卷組(Volume Group)——LVM卷組類似於非LVM系統中的物理硬盤,其由物理卷PV組成。可以在卷組上創建一個或多個"LV分區"(邏輯卷),VG卷組由一個或多個物理卷PV組成。
邏輯卷(logical volume)——LVM的邏輯卷類似於非LVM系統中的硬盤分區,在邏輯卷之上可以建立文件系統(比如/home或者/usr等)。
PE(physical extent)——每一個物理卷被劃分為稱為PE(Physical Extents)的基本單元,具有唯一編號的PE是可以被LVM尋址的最小單元。PE的大小是可配置的,默認為4MB。
LE(logical extent)——邏輯卷也被劃分為被稱為LE(Logical Extents) 的可被尋址的基本單位。在同一個卷組中,LE的大小和PE是相同的,並且一一對應。
如下圖所示PV、VG、LV三者關系:
設備文件名: /dev/卷組名/邏輯卷名 或 /dev/mapper/卷組名-邏輯卷名
物理卷管理命令:pv
pvcreate(創建pv), pvremove(移除pv), pvmove(移除卷內數據), pvscan(顯示所有的pv卷), pvs(查看pv卷簡要信息), pvdisplay (看pv卷詳細信息)
卷組管理命令:vg
vgcreate(創建vg), vgremove(移除vg), vgs(查看vg卷簡要信息), vgdisplay (查看vg卷詳細信息), vgextend(擴展vg卷組), vgreduce(縮減vg卷組), vgrename (改名)
# vgcreate -s PE_size 指定PE的大小 ,默認是4M
邏輯卷的管理命令:lv
lvcreate, lvremove, lvs, lvdisplay , lvextend(擴展lv卷組) , lvreduce(縮減lv卷組)
# lvcreate 創建lv邏輯卷
-n 指定lv名稱
-L 邏輯卷大小
-s 創建快照
-p 指定模式
# lvextend 擴展lv大小
-L [+] 5G 擴展[了]到5G
獲取以上命令幫助方法: # command -h ,例: #lvcreate -h
配置管理LVM實驗(邏輯卷管理)
系統環境:
系統:Centos 7.4 最小化安裝
LVM管理工具:lvm2-2.02.171-8.el7.x86_64
磁盤分區:掛載/dev/sdb 、/dev/sdc 、/dev/sdd、/dev/sde 、/dev/sdf、 /dev/sdg 共6塊磁盤
實驗目的:
1、通過LVM管理工具,分別創建pv、vg 和lvm。
2、模擬擴展和縮減LV,模擬擴展或縮減VG
3、創建lv快照
4、卸載LVM,刪除LVM
實驗步驟:
一、設置磁盤(虛擬機中增加6塊10G磁盤),安裝LVM 管理工具。
1、在Vmware 虛擬機中,增加6塊磁盤 。
2、查看系統版本,驗證lvm*管理工具是否安裝 並查看磁盤信息
[root@study ~]# cat /etc/redhat-release CentOS Linux release 7.4.1708 (Core) [root@study ~]# rpm -qa |grep lvm* lvm2-libs-2.02.171-8.el7.x86_64 lvm2-2.02.171-8.el7.x86_64 [root@study ~]# fdisk -l | grep "^Disk./dev" Disk /dev/sda: 128.8 GB, 128849018880 bytes, 251658240 sectors Disk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/sdc: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/sdd: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/sde: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/sdf: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/sdg: 10.7 GB, 10737418240 bytes, 20971520 sectors Disk /dev/mapper/VG-root: 16.1 GB, 16106127360 bytes, 31457280 sectors Disk /dev/mapper/VG-home: 21.5 GB, 21474836480 bytes, 41943040 sectors Disk /dev/mapper/VG-var: 10.7 GB, 10737418240 bytes, 20971520 sectors
二、對增加的磁盤進行分區並修改分區類型為8e(Linux LVM),並驗證分區結果
[root@study ~]# echo 'n > p > 1 > > > t > 8e > w '|fdisk /dev/sdb ## 為/dev/sdb磁盤創建分區1 ,分配分區大小為磁盤總空間。並調整類型為8e(LVM) 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 0x3bb09eb9. Command (m for help): Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): Partition number (1-4, default 1): First sector (2048-20971519, default 2048): Using default value 2048 Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519): Using default value 20971519 Partition 1 of type Linux and of size 10 GiB is set Command (m for help): Selected partition 1 Hex code (type L to list all codes): Changed type of partition 'Linux' to 'Linux LVM' Command (m for help): The partition table has been altered! Calling ioctl() to re-read partition table. Syncing disks. [root@study ~]... ## 以同樣的命令方式對其他5塊磁盤進行操作 [root@study ~]# fdisk -l | grep "LVM$" ## 驗證磁盤分區結果 /dev/sda3 12584960 251658239 119536640 8e Linux LVM /dev/sdb1 2048 20971519 10484736 8e Linux LVM /dev/sdc1 2048 20971519 10484736 8e Linux LVM /dev/sdd1 2048 20971519 10484736 8e Linux LVM /dev/sde1 2048 20971519 10484736 8e Linux LVM /dev/sdf1 2048 20971519 10484736 8e Linux LVM /dev/sdg1 2048 20971519 10484736 8e Linux LVM [root@study ~]# reboot ## 內核重讀磁盤分區 [root@study ~]# cat /proc/partitions | grep "1$" ##驗證內核是否加載了磁盤分區 8 1 2097152 sda1 8 17 10484736 sdb1 8 33 10484736 sdc1 8 49 10484736 sdd1 8 65 10484736 sde1 8 81 10484736 sdf1 8 97 10484736 sdg1
三、創建PV 物理卷
[root@study ~]# pvcreate /dev/sd{b..e}1 Physical volume "/dev/sdb1" successfully created. Physical volume "/dev/sdc1" successfully created. Physical volume "/dev/sdd1" successfully created. Physical volume "/dev/sde1" successfully created. [root@study ~]# pvs PV VG Fmt Attr PSize PFree /dev/sda3 VG lvm2 a-- <114.00g <69.00g /dev/sdb1 lvm2 --- <10.00g <10.00g /dev/sdc1 lvm2 --- <10.00g <10.00g /dev/sdd1 lvm2 --- <10.00g <10.00g /dev/sde1 lvm2 --- <10.00g <10.00g [root@study ~]# pvscan PV /dev/sda3 VG VG lvm2 [<114.00 GiB / <69.00 GiB free] PV /dev/sdd1 lvm2 [<10.00 GiB] PV /dev/sde1 lvm2 [<10.00 GiB] PV /dev/sdc1 lvm2 [<10.00 GiB] PV /dev/sdb1 lvm2 [<10.00 GiB] Total: 5 [153.99 GiB] / in use: 1 [<114.00 GiB] / in no VG: 4 [<40.00 GiB] [root@study ~]# pvdisplay --- Physical volume --- PV Name /dev/sda3 VG Name VG PV Size <114.00 GiB / not usable 3.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 29183 Free PE 17663 Allocated PE 11520 PV UUID 2Ksdp4-23Ia-jnvA-BeO4-31O2-chlO-I2CQTc "/dev/sdd1" is a new physical volume of "<10.00 GiB" --- NEW Physical volume --- PV Name /dev/sdd1 VG Name PV Size <10.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID MjYIgP-smsp-E72x-4eOQ-kQpG-vIAA-axaKXp ...
說明:#pvcreate /dev/sd{b..g}1 創建pv物理卷;
# pvdisplay | pvs | pvscan 查看pv狀態信息
PV Name, 物理卷名;
VG Name, 所屬卷組名;
PV Size,物理卷大小;
PV UUID ,PV UUID 號
四、創建myvg 卷組 ,指定PE大小為16M
[root@study ~]# vgcreate /dev/myvg -s 16M /dev/sd{b..e}1 Volume group "myvg" successfully created [root@study dev]# vgs VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 4 0 0 wz--n- <39.94g <39.94g [root@study dev]# vgscan Reading volume groups from cache. Found volume group "VG" using metadata type lvm2 Found volume group "myvg" using metadata type lvm2 [root@study dev]# pvs PV VG Fmt Attr PSize PFree /dev/sda3 VG lvm2 a-- <114.00g <69.00g /dev/sdb1 myvg lvm2 a-- 9.98g 9.98g /dev/sdc1 myvg lvm2 a-- 9.98g 9.98g /dev/sdd1 myvg lvm2 a-- 9.98g 9.98g /dev/sde1 myvg lvm2 a-- 9.98g 9.98g [root@study dev]# pvdisplay --- Physical volume --- PV Name /dev/sdb1 VG Name myvg PV Size <10.00 GiB / not usable 15.00 MiB Allocatable yes PE Size 16.00 MiB Total PE 639 Free PE 639 Allocated PE 0 PV UUID ZbZyCp-MiC8-Nnha-npKK-aVsr-ahTB-CIs2ok ... [root@study dev]# vgdisplay --- Volume group --- VG Name myvg System ID Format lvm2 Metadata Areas 4 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 4 Act PV 4 VG Size <39.94 GiB PE Size 16.00 MiB Total PE 2556 Alloc PE / Size 0 / 0 Free PE / Size 2556 / <39.94 GiB VG UUID hgiXN3-e8Z1-NLL2-tJ2q-hVtD-t2BO-i7uafQ
說明:#vgcreate myvg -s 16M /dev/sd{b..e}1 創建myvg1卷組,並指定PE大小為16M;
# pvdisplay | pvs | pvscan 查看pv狀態信息
PE Size ,PE的大小16M,默認為4MB
Total PE,PE的總數量
Free PE / Size ,空閑PE的數量及大小
# vgdisplay | vgs |vgscan 查看vg狀態信息
VG name,VG名字
VG Size ,VG容量
五、創建mylv 邏輯卷並查看pv,vg及lv狀態, 格式化lv邏輯卷並實現開機掛載
[root@study dev]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert home VG -wi-ao---- 20.00g root VG -wi-ao---- 15.00g var VG -wi-ao---- 10.00g mylv myvg -wi-a----- 20.00g [root@study dev]# lvscan ACTIVE '/dev/VG/root' [15.00 GiB] inherit ACTIVE '/dev/VG/home' [20.00 GiB] inherit ACTIVE '/dev/VG/var' [10.00 GiB] inherit ACTIVE '/dev/myvg/mylv' [20.00 GiB] inherit [root@study dev]# lvdisplay ... --- Logical volume --- LV Path /dev/myvg/mylv LV Name mylv VG Name myvg LV UUID 7aaK0H-sUpW-KYBL-awJl-1Jr9-Sewp-trSQi0 LV Write Access read/write LV Creation host, time study.itwish.cn, 2018-02-04 16:33:22 +0800 LV Status available # open 0 LV Size 20.00 GiB Current LE 1280 Segments 3 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:3 [root@study dev]# pvs PV VG Fmt Attr PSize PFree /dev/sda3 VG lvm2 a-- <114.00g <69.00g /dev/sdb1 myvg lvm2 a-- 9.98g 0 /dev/sdc1 myvg lvm2 a-- 9.98g 0 /dev/sdd1 myvg lvm2 a-- 9.98g 9.95g /dev/sde1 myvg lvm2 a-- 9.98g 9.98g [root@study dev]# pvscan PV /dev/sda3 VG VG lvm2 [<114.00 GiB / <69.00 GiB free] PV /dev/sdb1 VG myvg lvm2 [9.98 GiB / 0 free] PV /dev/sdc1 VG myvg lvm2 [9.98 GiB / 0 free] PV /dev/sdd1 VG myvg lvm2 [9.98 GiB / 9.95 GiB free] PV /dev/sde1 VG myvg lvm2 [9.98 GiB / 9.98 GiB free] Total: 5 [153.93 GiB] / in use: 5 [153.93 GiB] / in no VG: 0 [0 ] [root@study dev]# vgs VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 4 1 0 wz--n- <39.94g <19.94g [root@study dev]# vgscan Reading volume groups from cache. Found volume group "VG" using metadata type lvm2 Found volume group "myvg" using metadata type lvm2 [root@study dev]# vgdisplay ... --- Volume group --- VG Name myvg System ID Format lvm2 Metadata Areas 4 Metadata Sequence No 2 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 0 Max PV 0 Cur PV 4 Act PV 4 VG Size <39.94 GiB PE Size 16.00 MiB Total PE 2556 Alloc PE / Size 1280 / 20.00 GiB Free PE / Size 1276 / <19.94 GiB VG UUID hgiXN3-e8Z1-NLL2-tJ2q-hVtD-t2BO-i7uafQ [root@study dev]# ls /dev/mapper/ control myvg-mylv VG-home VG-root VG-var [root@study dev]# ls /dev/myvg/ mylv [root@study dev]# mke2fs -t ext4 -m 2 -L mylvdata /dev/mapper/myvg-mylv ##創建文件系統 mke2fs 1.42.9 (28-Dec-2013) Filesystem label=mylvdata OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 1310720 inodes, 5242880 blocks 104857 blocks (2.00%) reserved for the super user First data block=0 Maximum filesystem blocks=2153775104 160 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 4096000 Allocating group tables: done Writing inode tables: done Creating journal (32768 blocks): done Writing superblocks and filesystem accounting information: done [root@study dev]# mount /dev/mapper/myvg-mylv /mylv/ ##掛載 [root@study dev]# ls /mylv/ lost+found [root@study dev]# mount | grep "^/dev" /dev/mapper/VG-root on / type ext4 (rw,relatime,seclabel,data=ordered) /dev/sda1 on /boot type ext4 (rw,relatime,seclabel,data=ordered) /dev/mapper/VG-home on /home type ext4 (rw,relatime,seclabel,data=ordered) /dev/mapper/VG-var on /var type ext4 (rw,relatime,seclabel,data=ordered) /dev/mapper/myvg-mylv on /mylv type ext4 (rw,relatime,seclabel,data=ordered) [root@study dev]# df -h | grep "^/dev" /dev/mapper/VG-root 15G 1.2G 13G 9% / /dev/sda1 2.0G 116M 1.7G 7% /boot /dev/mapper/VG-home 20G 45M 19G 1% /home /dev/mapper/VG-var 9.8G 200M 9.1G 3% /var /dev/mapper/myvg-mylv 20G 45M 20G 1% /mylv [root@study dev]# vi /etc/fstab ## 配置開機自動掛載 # # /etc/fstab # Created by anaconda on Sun Jan 28 12:27:18 2018 # # Accessible filesystems, by reference, are maintained under '/dev/disk' # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info # /dev/mapper/VG-root / ext4 defaults 1 1 UUID=085b953d-5803-45df-b9d9-dc0ff7f92a3d /boot ext4 defa ults 1 2 /dev/mapper/VG-home /home ext4 defaults 1 2 /dev/mapper/VG-var /var ext4 defaults 1 2 UUID=4169cca6-5a09-46fe-a2a7-64eba563b00a swap swap defa ults 0 0 /dev/myvg/mylv /mylv ext4 defaults 0 2
說明:#lvcreate -n mylv -L 20G myvg 從myvg 卷組中分配20G並創建mylv邏輯卷;-n 指定LVM名字 ,-L 分配容量大小
# lvdisplay | lvs | lvscan 查看lv狀態信息
LV Path ,LV的路徑
LV Name, LV的名字VG Name所屬的VG
LV Size , LV的大小
六、擴展或縮減mylv 邏輯卷
LVM最大的優勢是可以對磁盤進行動態管理,而且不會丟失現有的數據。
1、擴展LVM的思路:
先確定擴展的大小,並確保所屬的卷組有足夠的剩余空間
擴展物理邊界 ,
卸載邏輯卷umount ;
通過命令e2fsck檢查lv邏輯卷 ;
# lvextend -L 【+】Size /path/to/lv_device
擴展邏輯邊界
# resize2fs /path/to/lv_device Size
[root@study ~]# cp -af /boot/ /mylv/ [root@study ~]# ls /mylv/ boot lost+found [root@study ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ... mylv myvg -wi-a----- 20.00g [root@study ~]# df -lh .. /dev/mapper/myvg-mylv 20G 154M 19G 1% /mylv ... [root@study ~]# vgs ##確保剩余空間 ,擴展的大小必須小於卷組剩余空間大小,myvg剩余vg大小為19.94G VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 4 1 0 wz--n- <39.94g <19.94g [root@study ~]# umount /mylv/ ##卸載磁盤分區/mylv/ [root@study ~]# e2fsck -fy /dev/mapper/myvg-mylv ##檢查並修復磁盤 e2fsck 1.42.9 (28-Dec-2013) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information mylvdata: 338/1310720 files (0.3% non-contiguous), 154377/5242880 blocks [root@study ~]# lvextend -L +5G /dev/mapper/myvg-mylv ##為LV邏輯卷擴展增加5G空間 Size of logical volume myvg/mylv changed from 20.00 GiB (1280 extents) to 25.00 GiB (1600 extents). Logical volume myvg/mylv successfully resized. [root@study ~]# lvs ##lv卷增加到25G空間 LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ... mylv myvg -wi-ao---- 25.00g [root@study ~]# resize2fs /dev/mapper/myvg-mylv ##為/dev/mapper/myvg-mylv擴展邏輯邊界 resize2fs 1.42.9 (28-Dec-2013) Filesystem at /dev/mapper/myvg-mylv is mounted on /mylv; on-line resizing required old_desc_blocks = 3, new_desc_blocks = 4 The filesystem on /dev/mapper/myvg-mylv is now 6553600 blocks long. [root@study ~]# df -lh ##查看磁盤大小 Filesystem Size Used Avail Use% Mounted on ... /dev/mapper/myvg-mylv 25G 154M 24G 1% /mylv [root@study ~]# ls /mylv/ ##確認磁盤數據存在 boot lost+found
2、縮減LVM思路:
卸載邏輯卷umount ;
通過命令e2fsck檢查lv邏輯卷 ;
縮減LVM邏輯卷邏輯邊界(確保縮減後的空間大小依然能存儲原有的所有數據);
# resize2fs /path/to/lv_device Size
縮減物理邊界
# lvreduce -L [-] size /path/to/lv_devcie
重新掛載
[root@study ~]# lvs ##確認lv卷空間大小 LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ... mylv myvg -wi-ao---- 25.00g [root@study ~]# df -lh ##查看磁盤大小 Filesystem Size Used Avail Use% Mounted on ... /dev/mapper/myvg-mylv 25G 154M 24G 1% /mylv [root@study ~]# umount /dev/myvg/mylv [root@study ~]# e2fsck -fy /dev/mapper/myvg-mylv e2fsck 1.42.9 (28-Dec-2013) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information mylvdata: 338/1638400 files (0.3% non-contiguous), 174937/6553600 blocks [root@study ~]# resize2fs /dev/mapper/myvg-mylv 15G ##縮減邏輯邊界空間大小為15G resize2fs 1.42.9 (28-Dec-2013) Resizing the filesystem on /dev/mapper/myvg-mylv to 3932160 (4k) blocks. The filesystem on /dev/mapper/myvg-mylv is now 3932160 blocks long. [root@study ~]# lvreduce -L 15G /dev/mapper/myvg-mylv ##縮減lv卷大小為15G WARNING: Reducing active logical volume to 15.00 GiB. THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce myvg/mylv? [y/n]: y Size of logical volume myvg/mylv changed from 25.00 GiB (1600 extents) to 15.00 GiB (960 extents). Logical volume myvg/mylv successfully resized. [root@study ~]# mount /dev/mapper/myvg-mylv /mylv/ [root@study ~]# df -lh Filesystem Size Used Avail Use% Mounted on ... /dev/mapper/myvg-mylv 15G 150M 15G 2% /mylv [root@study ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ... mylv myvg -wi-ao---- 15.00g
說明:# e2fsck -fy /dev/mapper/myvg-mylv 強制檢查文件系統; -f 強制
#lvreduce -L 15G /dev/myvg-mylv 分配到mylv邏輯卷大小為5G; -L 分配容量大小
# lvextend -L +5G /dev/mapper/myvg-mylv 擴展5G容量分配到mylv1邏輯卷; -L 分配容量大小 +5G 擴展5G
# resize2fs /dev/mapper/myvg-mylv 擴展文件系統與邏輯卷大小一致
# resize2fs /dev/mapper/myvg-mylv 15G 縮減邏輯邊界空間大小為15G
七、擴展或縮減myvg 卷組
1、擴展vg卷組思路
準備要添加的物理卷
添加物理卷至卷組中
# vgextend vg_name /path/to/pv_devcie
[root@study ~]# pvcreate /dev/sd{f,g}1 Physical volume "/dev/sdf1" successfully created. Physical volume "/dev/sdg1" successfully created. [root@study ~]# vgs VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 4 1 0 wz--n- <39.94g <24.94g [root@study ~]# vgextend myvg /dev/sd{g,f}1 ##擴展2個磁盤分區到myvg卷組 Volume group "myvg" successfully extended [root@study ~]# vgs ## 卷組大小增加20G空間 VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 6 1 0 wz--n- <59.91g <44.91g
2、縮減vg卷組思路
去頂要移除的物理卷的總空間大小,要小於vg當前的空閑空間大小
將要移除的物理卷上的數據移動至其他PV
# pvmove /path/to/pv_device
縮減vg
# vgremove vg_name /path/to/pv_device
[root@study ~]# vgs ##磁盤卷組空閑free空間為44.91G VG #PV #LV #SN Attr VSize VFree VG 1 3 0 wz--n- <114.00g <69.00g myvg 6 1 0 wz--n- <59.91g <44.91g [root@study ~]# pvs ## 確認分區/dev/sdb1 和分區/dev/sdc1分區被使用,存有數據 PV VG Fmt Attr PSize PFree /dev/sda3 VG lvm2 a-- <114.00g <69.00g /dev/sdb1 myvg lvm2 a-- 9.98g 0 /dev/sdc1 myvg lvm2 a-- 9.98g <4.97g /dev/sdd1 myvg lvm2 a-- 9.98g 9.98g /dev/sde1 myvg lvm2 a-- 9.98g 9.98g /dev/sdf1 myvg lvm2 a-- 9.98g 9.98g /dev/sdg1 myvg lvm2 a-- 9.98g 9.98g [root@study ~]# pvmove /dev/sdf1 ##轉移數據 No data to move for myvg [root@study ~]# pvmove /dev/sdg1 No data to move for myvg [root@study ~]# vgreduce myvg /dev/sd{f,g}1 ##縮減vg卷組,刪除分區/dev/sdf1 和分區/dev/sdg1 Removed "/dev/sdg1" from volume group "myvg" Removed "/dev/sdf1" from volume group "myvg" [root@study ~]# pvremove /dev/sd{g,f}1 ##刪除pv卷 Labels on physical volume "/dev/sdg1" successfully wiped. Labels on physical volume "/dev/sdf1" successfully wiped.
說明:#vgextend myvg /dev/sd{f,g}1 擴展分區/dev/sdf1和分區/dev/sdg1到vg卷組
#pvmove /dev/sdg1 將分區/dev/sdg1中的數據轉移到其他分區
# vgreduce myvg /dev/sd{f,g}1 在myvg卷組中縮減刪除pv分區/dev/sdg1,/dev/sdf1
# pvremove /dev/sd{g,f}1 刪除pv卷
八、創建LVM快照卷,完成數據備份及還原
1、實現思路
創建快照
# lvcreate -s -L size -n Name -p r /path/to/original_lv_device
掛載
# mount /dev/mapper/myvg_name /media 例 # mount /dev/mapper/myvg-test--snap /media/
把掛載數據備份
tar -zcf /root/media.tar.gz /media/*
卸載快照卷 ,移除快照卷
lvremove /dev/myvg/test-snap
模擬刪除lv數據,通過快照數據進行還原
[root@study ~]# lvcreate -s -L 10G -n mylvspare -p r /dev/mapper/myvg-mylv Using default stripesize 64.00 KiB. Logical volume "mylvspare" created. [root@study ~]# mount /dev/mapper/myvg-mylvspare /media/ mount: /dev/mapper/myvg-mylvspare is write-protected, mounting read-only [root@study ~]# ls /media/ boot lost+found [root@study ~]# tar -zcf /root/spare.tar.gz /media/* tar: Removing leading `/' from member names [root@study ~]# ls -lh total 102M -rw-------. 1 root root 1.8K Jan 28 12:33 anaconda-ks.cfg drwxrwxr-x. 2 root root 36K Sep 5 21:38 Packages -rw-r--r--. 1 root root 102M Feb 4 18:11 spare.tar.gz [root@study ~]# umount /dev/mapper/myvg-mylvspare [root@study ~]# lvremove /dev/mapper/myvg-mylvspare Do you really want to remove active logical volume myvg/mylvspare? [y/n]: y Logical volume "mylvspare" successfully removed [root@study ~]# rm -rf /mylv/boot/ ##模擬刪除LV卷中數據,通過備份的快照數據進行還原 [root@study mylv]# cd /root/ [root@study ~]# ls anaconda-ks.cfg Packages spare.tar.gz [root@study ~]# tar -zxf spare.tar.gz [root@study ~]# ls anaconda-ks.cfg media Packages spare.tar.gz [root@study mylv]# cp -af /root/media/* /mylv/ [root@study mylv]# ls ## 通過快照數據進行數據還原 config-3.10.0-693.el7.x86_64 efi grub grub2 initramfs-0-rescue-aa42d80ce1774acf8f5de007d85e5ef1.img initramfs-3.10.0-693.el7.x86_64.img initramfs-3.10.0-693.el7.x86_64kdump.img initrd-plymouth.img lost+found mylv symvers-3.10.0-693.el7.x86_64.gz System.map-3.10.0-693.el7.x86_64 vmlinuz-0-rescue-aa42d80ce1774acf8f5de007d85e5ef1 vmlinuz-3.10.0-693.el7.x86_64
九、卸載刪除lVM
[root@study media]# umount /dev/mapper/myvg-mylv [root@study media]# lvremove /dev/mapper/myvg-mylv Do you really want to remove active logical volume myvg/mylv? [y/n]: y Logical volume "mylv" successfully removed [root@study media]# vgremove myvg Volume group "myvg" successfully removed [root@study media]# pvremove /dev/sd{b..e}1 Labels on physical volume "/dev/sdb1" successfully wiped. Labels on physical volume "/dev/sdc1" successfully wiped. Labels on physical volume "/dev/sdd1" successfully wiped. Labels on physical volume "/dev/sde1" successfully wiped.
至此 ,整體部署配置LVM實驗完成 。
Centos 7.4 服務器配置LVM(邏輯卷管理)