Linux高階檔案系統管理(8)
阿新 • • 發佈：2019-01-04
如果您的 Linux 伺服器有多個使用者經常存取資料時,為了維護所有使用者在硬碟容量的公平使用,磁碟配額 (Quota) 就是一項非常有用的工具,另外,如果你的使用者常常抱怨磁碟容量不夠用,那麼更進階的檔案系統就得要學習,本章我們會介紹磁碟陣列 (RAID),及邏輯卷軸檔案系統 (LVM),這些工具都可以幫助你管理與維護使用者可用的磁碟容量.
Quota 磁碟配額配置
Quota 這個玩意兒就字面上的意思來看,就是有多少『限額』的意思啦,如果是用在零用錢上面,就是類似『有多少零用錢一個月』的意思之類的,如果是在計算機主機的磁碟使用量上呢? 以 Linux 來說,就是有多少容量限制的意思,我們可以使用 quota 來讓磁碟的容量使用較為公平,下面我們會介紹什麼是 quota 然後以一個完整的範例來介紹 quota 的使用作用.
由於Linux是一個多使用者管理的作業系統，而Linux預設情況下並不限制每個使用者使用磁碟空間的大小，假如某個使用者疏忽或者惡意佔滿磁碟空間，將導致系統磁碟無法寫入甚至崩潰；為了保證系統磁
盤的有足夠的剩餘空間，我們需要對使用者和組進行磁碟空間使用限制。
磁碟配額限制類型：
⦁ 限制使用者和組,對磁碟空間的使用量
⦁ 限制使用者和組,在磁碟內建立檔案的個數
磁碟配額限制級別：
⦁ 軟限制：低階限制,此限制可以突破,突破時會被警告,超出部分會有寬限天數,寬限天數到期後超出部分被清空,軟限制不能超過硬限制
⦁ 硬限制：絕對限制,此限制不會被突破,達到指定限制後無法使用更多空間
⦁ 寬限天數：當有資料超過軟限制後,超出部分會被計時,寬限天數到期後超出部分資料將被清空,寬限天數預設是7天
注：磁碟配額是針對分割槽進行設定的,無法實現,"某使用者在系統中共計只能使用50MB磁碟空間",只能設定某使用者在/home分割槽能使用30M這樣的限制.切記：磁碟配額是針對分割槽的!
精簡模式下沒有此命令,執行 yum install -y quota 安裝
◆檢查核心是否支援配額◆
[[email protected] ~]# cat /boot/config-3.10.0-693.el7.x86_64 |grep "CONFIG_QUOTA"
CONFIG_QUOTA=y
CONFIG_QUOTA_NETLINK_INTERFACE=y
# CONFIG_QUOTA_DEBUG is not set
CONFIG_QUOTA_TREE=y
CONFIG_QUOTACTL=y
CONFIG_QUOTACTL_COMPAT=y◆檢查指定分割槽的掛載屬性是否滿足條件◆
[[email protected] ~]# dumpe2fs -h /dev/vdb |grep "Default mount options"
dumpe2fs 1.42.9 (28-Dec-2013)
Default mount options: user_xattr acl
#檢查結果中是否包含,usrquota,grpquota兩個掛載屬性◆quotacheck 生成使用者和組的配置檔案◆
[[email protected] ~]# quotacheck --help
Utility for checking and repairing quota files.
quotacheck [-gucbfinvdmMR] [-F <quota-format>] filesystem|-a
語法格式：[ quota [選項] [分割槽名] ]
-a #掃描/etc/mtab檔案中所有啟用磁碟配額功能的分割槽.如果加入此引數,命令後面就不需要加入分割槽名了
-u #建立使用者配額的配置檔案,即生成aquota.user
-g #建立組配額的配置檔案,即aquota.group
-v #顯示掃描過程
-c #清除原有的配置檔案,重新建立新的配置檔案◆edquota 編輯配額檔案,設定指定限制大小◆
[[email protected] ~]# edquota --help
edquota: Usage:
edquota [-rm] [-u] [-F formatname] [-p username] [-f filesystem] username ...
edquota [-rm] -g [-F formatname] [-p groupname] [-f filesystem] groupname ...
edquota [-u|g] [-F formatname] [-f filesystem] -t
edquota [-u|g] [-F formatname] [-f filesystem] -T username|groupname ...
語法格式：[ edquota [選項] [使用者名稱或組名] ]
-u #使用者名稱
-g #組名
-t #設定寬限時間
-p #複製磁碟配額規則,不需要每一個使用者或者組都手動設定一遍
#edquota -p 模板使用者 -u 目標使用者
#注：配置檔案中所寫大小預設單位KB◆啟動quota配額管理◆
[[email protected] ~]# quotaon --help
quotaon: Usage:
quotaon [-guvp] [-F quotaformat] [-x state] -a
quotaon [-guvp] [-F quotaformat] [-x state] filesys ...
語法格式：[ quotaon [選項] [分割槽名] ]
-a #根據/etc/mtab檔案啟動所有分割槽的磁碟配額（不寫分割槽名）
-u #啟動使用者的磁碟配額
-g #啟動組的磁碟配額
-v #顯示啟動過程資訊◆關閉quota配額管理◆
[[email protected] ~]# quotaoff --help
quotaoff: Usage:
quotaoff [-guvp] [-F quotaformat] [-x state] -a
quotaoff [-guvp] [-F quotaformat] [-x state] filesys ...
語法格式：[ quotaoff [選項] [分割槽名] ]
-a #根據/etc/mtab檔案關閉所有分割槽的磁碟配額（不寫分割槽名）
-u #關閉使用者的磁碟配額
-g #關閉組的磁碟配額
-v #顯示關閉過程資訊◆quota 檢視指定使用者和組的配額資訊◆
[[email protected] ~]# quota --hlep
quota: unrecognized option '--hlep'
quota: Usage: quota [-guqvswim] [-l | [-Q | -A]] [-F quotaformat]
quota [-qvswim] [-l | [-Q | -A]] [-F quotaformat] -u username ...
quota [-qvswim] [-l | [-Q | -A]] [-F quotaformat] -g groupname ...
quota [-qvswugQm] [-F quotaformat] -f filesystem ...
語法格式：[ quota [選項] [使用者名稱] ]
-u #使用者名稱
-g #組名
-v #顯示詳細資訊
-s #以常見單位顯示大小◆repquota 檢視指定分割槽的磁碟配額◆
[[email protected] ~]# repquota --help
repquota: Utility for reporting quotas.
Usage:
repquota [-vugsi] [-c|C] [-t|n] [-F quotaformat] (-a | mntpoint)
語法格式：[ repquota [選項] [分割槽名] ]
-u #查詢使用者配額
-g #查詢組配額
-v #顯示詳情
-s #以常見單位顯示◆setquota 非互動設定磁碟配額命令◆
[[email protected] ~]# setquota --help
setquota: Usage:
setquota [-u|-g] [-rm] [-F quotaformat] <user|group>
<block-softlimit> <block-hardlimit> <inode-softlimit> <inode-hardlimit> -a|<filesystem>...
setquota [-u|-g] [-rm] [-F quotaformat] <-p protouser|protogroup> <user|group> -a|<filesystem>...
setquota [-u|-g] [-rm] [-F quotaformat] -b [-c] -a|<filesystem>...
setquota [-u|-g] [-F quotaformat] -t <blockgrace> <inodegrace> -a|<filesystem>...
setquota [-u|-g] [-F quotaformat] <user|group> -T <blockgrace> <inodegrace> -a|<filesystem>...
setquota -u 使用者名稱 軟(容) 硬(容) 軟(數) 硬(數) 分割槽名
注：這樣的非互動式的命令更適合寫入指令碼,而且假如有很多使用者的磁碟配額配置相同也可以用複製來實現。◆磁碟配額小實驗◆
⦁ 這裡有一塊未分割槽的磁碟/dev/sdb,手動分割槽並格式化.
⦁ 將磁碟配額開啟,並寫入開機自啟動列表.
⦁ 建立lyshark使用者,和temp組.
⦁ 配置lyshark的軟限制200M,硬限制500M,配置temp組軟限制100M,硬限制200M.
1.檢查系統是否支援配額
[[email protected] ~]# cat /boot/config-3.10.0-862.el7.x86_64 |grep "CONFIG_QUOTA"
CONFIG_QUOTA=y
CONFIG_QUOTA_NETLINK_INTERFACE=y
# CONFIG_QUOTA_DEBUG is not set
CONFIG_QUOTA_TREE=y
CONFIG_QUOTACTL=y
CONFIG_QUOTACTL_COMPAT=y2.檢視磁碟資訊
[[email protected] ~]# ll /dev/sd*
brw-rw---- 1 root disk 8, 0 6月 24 09:14 /dev/sda
brw-rw---- 1 root disk 8, 1 6月 24 09:14 /dev/sda1
brw-rw---- 1 root disk 8, 2 6月 24 09:14 /dev/sda2
brw-rw---- 1 root disk 8, 16 6月 24 09:14 /dev/sdb3.磁碟分割槽/dev/sdb,並格式化為ext4格式
[[email protected] ~]# parted /dev/sdb
GNU Parted 3.1
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) mkpart
Partition name? []? sdb1
File system type? [ext2]? ext2
Start? 1M
End? 10000M
(parted) p
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdb: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
1 1049kB 10.0GB 9999MB ext4 sdb1
(parted) q
Information: You may need to update /etc/fstab.
[[email protected] ~]# mkfs.ext4 /dev/sdb1
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
610800 inodes, 2441216 blocks
122060 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2151677952
75 block groups
32768 blocks per group, 32768 fragments per group
8144 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done4.建立掛載點,並掛載裝置
[[email protected] ~]# mkdir /sdb1
[[email protected] ~]# mount /dev/sdb1 /sdb1/
[[email protected] ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.4G 6.7G 17% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 6% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/sr0 4.2G 4.2G 0 100% /mnt
/dev/sdb1 9.1G 37M 8.6G 1% /sdb15.檢查分割槽是否支援配額 (主要看有沒有usrquota,grpquota)
[[email protected] ~]# dumpe2fs -h /dev/sdb1 |grep "Default mount options"
dumpe2fs 1.42.9 (28-Dec-2013)
Default mount options: user_xattr acl
[[email protected] ~]# cat /proc/mounts |grep "/dev/sdb1"
/dev/sdb1 /sdb1 ext4 rw,relatime,data=ordered 0 0
#上面沒有看到相關許可權,此時我們要重新掛載一下磁碟,加上許可權
[[email protected] ~]# mount -o remount,usrquota,grpquota /dev/sdb1
[[email protected] ~]# cat /proc/mounts |grep "/dev/sdb1"
/dev/sdb1 /sdb1 ext4 rw,relatime,quota,usrquota,grpquota,data=ordered 0 06.設定開機自動掛載分割槽,並開啟配額
[[email protected] ~]# ls -l /dev/disk/by-uuid/
total 0
lrwxrwxrwx 1 root root 10 Sep 21 20:07 13d5ccc2-52db-4aec-963a-f88e8edcf01c -> ../../sda1
lrwxrwxrwx 1 root root 9 Sep 21 20:07 2018-05-03-20-55-23-00 -> ../../sr0
lrwxrwxrwx 1 root root 10 Sep 21 20:07 4604dcf2-da39-455a-9719-e7c5833e566c -> ../../dm-0
lrwxrwxrwx 1 root root 10 Sep 21 20:47 939cbeb8-bc88-44aa-9221-50672111e123 -> ../../sdb1
lrwxrwxrwx 1 root root 10 Sep 21 20:07 f6a4b420-aa6a-4e66-bbb3-c8e8280a099f -> ../../dm-1
[[email protected] ~]# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Tue Sep 18 09:05:06 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/centos-root / xfs defaults 0 0
UUID=13d5ccc2-52db-4aec-963a-f88e8edcf01c /boot xfs defaults 0 0
/dev/mapper/centos-swap swap swap defaults 0 0
UUID=7d7f22ed-466e-4205-8efe-1b6184dc5e1b swap swap defaults 0 0
UUID=939cbeb8-bc88-44aa-9221-50672111e123 /sdb1 ext4 defaults,usrquota,grpquota 0 0
[[email protected] ~]# mount -o remount,usrquota,grpquota /dev/sdb17.生成配額檔案 quotackeck -ugv[分割槽名]
[[email protected] ~]# quotacheck -ugv /dev/sdb1
quotacheck: Your kernel probably supports journaled quota but you are not using it. Consider switching to journaled quota to avoid running quotacheck after an unclean shutdown.
quotacheck: Scanning /dev/sdb1 [/sdb1] done
quotacheck: Cannot stat old user quota file /sdb1/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /sdb1/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old user quota file /sdb1/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /sdb1/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Checked 3 directories and 0 files
quotacheck: Old file not found.
quotacheck: Old file not found.8.編輯限制,edquota -ugtp [使用者名稱/組名]
配置lyshark的軟限制200M,硬限制500M
[[email protected]localhost ~]# edquota -u lyshark
Disk quotas for user lyshark (uid 1000):
↓檔案系統 軟(容量) 硬(容量) I節點 軟(數) 硬(數)
Filesystem blocks soft hard inodes soft hard
/dev/sdb1 0 200M 500M 0 0 0配置temp組軟限制100M,硬限制200M.
[[email protected] ~]# edquota -g temp
Disk quotas for group temp (gid 1001):
Filesystem blocks soft hard inodes soft hard
/dev/sdb1 0 102400 204800 0 0 09.開啟配額,quota on/off -augv
[[email protected] ~]# quotaon -augv
/dev/sdb1 [/sdb1]: group quotas turned on
/dev/sdb1 [/sdb1]: user quotas turned on10.檢視指定使用者或組的配額,quota -ugvs
[[email protected] ~]# quota -ugvs
Disk quotas for user root (uid 0):
Filesystem space quota limit grace files quota limit grace
/dev/sdb1 20K 0K 0K 2 0 0
Disk quotas for group root (gid 0):
Filesystem space quota limit grace files quota limit grace
/dev/sdb1 20K 0K 0K 2 0 0LVM 邏輯卷管理器
LVM（Logical Volume Manager）邏輯卷管理,它是Linux環境下對磁碟分割槽進行管理的一種機制,普通的磁碟分割槽管理方式在分區劃分好之後就無法改變其大小,當一個邏輯分割槽存放不下某個檔案時,解決的方法通常是使用符號連結,或者使用調整分割槽大小的工具,但這只是暫時解決辦法,沒有從根本上解決問題.簡單來說LVM就是將物理磁碟融合成一個或幾個大的虛擬磁碟儲存池,按照我們的需求去儲存池劃分空間來使用,由於是虛擬的儲存池,所以劃分空間時可以自由的調整大小,如下：
LVM的組成部分：
⦁ 物理卷（PV，Physical Volume）：由磁碟或分割槽轉化而成
⦁ 卷組（VG，Volume Group）：將多個物理卷組合在一起組成了卷組,組成同一個卷組的可以是同一個硬碟的不同分割槽,也可以是不同硬碟上的不同分割槽,我們通常把卷組理解為一塊硬碟.
⦁ 邏輯卷（LV，Logical Volume）：把卷組理解為硬碟的話,那麼我們的邏輯卷則是硬碟上的分割槽,邏輯卷可以進行格式化,儲存資料.
⦁ 物理擴充套件（PE，Physical Extend）：PE卷組的最小儲存單元,PE所在的位置是VG卷組,即硬碟上,那麼我們可以把PE理解為硬碟上的扇區,預設是4MB,可自由配置.
這裡準備好4塊硬碟,無需分割槽與格式化.
[[email protected] ~]# ll /dev/sd[b-z]
brw-rw---- 1 root disk 8, 16 Sep 21 22:04 /dev/sdb
brw-rw---- 1 root disk 8, 32 Sep 21 22:04 /dev/sdc
brw-rw---- 1 root disk 8, 48 Sep 21 22:04 /dev/sdd
brw-rw---- 1 root disk 8, 64 Sep 21 22:04 /dev/sde◆PV 物理卷建立與移除◆
PV的建立
pvcreate [分割槽路徑],[分割槽路徑][.......]
[[email protected] ~]# ll /dev/sd[b-z]
brw-rw---- 1 root disk 8, 16 Sep 21 22:04 /dev/sdb
brw-rw---- 1 root disk 8, 32 Sep 21 22:04 /dev/sdc
brw-rw---- 1 root disk 8, 48 Sep 21 22:04 /dev/sdd
brw-rw---- 1 root disk 8, 64 Sep 21 22:04 /dev/sde
[[email protected] ~]# pvcreate /dev/sdb /dev/sdc #此處拿3塊硬碟建立
Physical volume "/dev/sdb" successfully created.
Physical volume "/dev/sdc" successfully created.
Physical volume "/dev/sdd" successfully created.
[[email protected] ~]# pvs #查詢建立好的硬碟
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb lvm2 --- 10.00g 10.00g
/dev/sdc lvm2 --- 10.00g 10.00g
/dev/sdd lvm2 --- 10.00g 10.00gPV的移除
pvremove [分割槽路徑]
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb lvm2 --- 10.00g 10.00g
/dev/sdc lvm2 --- 10.00g 10.00g
/dev/sdd lvm2 --- 10.00g 10.00g
[[email protected] ~]# pvremove /dev/sdd #移除/dev/sdd
Labels on physical volume "/dev/sdd" successfully wiped.
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb lvm2 --- 10.00g 10.00g
/dev/sdc lvm2 --- 10.00g 10.00g◆VG 卷組建立與移除◆
建立VG卷組,VG卷組要在PV中選擇
vgcreate -s [指定PE大小] [VG卷組名] [分割槽路徑] [分割槽路徑][.....]
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb lvm2 --- 10.00g 10.00g
/dev/sdc lvm2 --- 10.00g 10.00g
[[email protected] ~]# vgcreate -s 4M my_vg /dev/sdb /dev/sdc #此處就是建立一個VG卷組
Volume group "my_vg" successfully created
[[email protected] ~]# vgs
VG #PV #LV #SN Attr VSize VFree
centos 1 2 0 wz--n- <9.00g 0
my_vg 2 0 0 wz--n- 19.99g 19.99g #這就是VG卷組,名字是my_vg給當前my_vg卷組,新增一塊新的PV,也就是擴展卷組
vgextend [卷組名] [物理卷分割槽]
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb my_vg lvm2 a-- <10.00g <10.00g
/dev/sdc my_vg lvm2 a-- <10.00g <10.00g
/dev/sdd lvm2 --- 10.00g 10.00g #這個物理卷沒有劃分卷組
[[email protected] ~]# vgextend my_vg /dev/sdd #新增一個PV到指定卷組
Volume group "my_vg" successfully extended
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb my_vg lvm2 a-- <10.00g <10.00g
/dev/sdc my_vg lvm2 a-- <10.00g <10.00g
/dev/sdd my_vg lvm2 a-- <10.00g <10.00g #已被劃分到my_vg卷組在VG卷組裡移除一個PV（移除單個PG）
vgreduce [卷組名] [物理卷分割槽]
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb my_vg lvm2 a-- <10.00g <10.00g
/dev/sdc my_vg lvm2 a-- <10.00g <10.00g
/dev/sdd my_vg lvm2 a-- <10.00g <10.00g
[[email protected] ~]# vgreduce my_vg /dev/sdd #將/dev/sdd從my_vg卷組裡移除
Removed "/dev/sdd" from volume group "my_vg"
[[email protected] ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 centos lvm2 a-- <9.00g 0
/dev/sdb my_vg lvm2 a-- <10.00g <10.00g
/dev/sdc my_vg lvm2 a-- <10.00g <10.00g
/dev/sdd lvm2 --- 10.00g 10.00g移除整個VG卷組
vgremove [卷組名]
[[email protected] ~]# vgs
VG #PV #LV #SN Attr VSize VFree
centos 1 2 0 wz--n- <9.00g 0
my_vg 2 0 0 wz--n- 19.99g 19.99g
[[email protected] ~]# vgremove my_vg #移除整個卷組
Volume group "my_vg" successfully removed
[[email protected] ~]# vgs
VG #PV #LV #SN Attr VSize VFree
centos 1 2 0 wz--n- <9.00g 0
[[email protected] ~]#
移除空的物理卷VG
vgreduce -a [卷組名]
[[email protected] ~]# vgs
VG #PV #LV #SN Attr VSize VFree
centos 1 2 0 wz--n- <9.00g 0
my_vg 3 0 0 wz--n- <29.99g <29.99g
[[email protected] ~]# vgreduce -a my_vg #只移除空卷組
Removed "/dev/sdb" from volume group "my_vg"
Removed "/dev/sdc" from volume group "my_vg"
[[email protected] ~]# vgs
VG #PV #LV #SN Attr VSize VFree
centos 1 2 0 wz--n- <9.00g 0
my_vg 1 0 0 wz--n- <10.00g <10.00g
◆LV 邏輯卷建立與移除◆
建立LVM
lvcreate -L [指定大小] -n [LV名字] [VG卷組:從哪個卷組裡劃分]
[[email protected] ~]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
root centos -wi-ao---- <8.00g
swap centos -wi-ao---- 1.00g
[[email protected] ~]# lvcreate -L 10G -n my_lv my_vg #建立LVM邏輯卷
Logical volume "my_lv" created.
[[email protected] ~]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
root centos -wi-ao---- <8.00g
swap centos -wi-ao---- 1.00g
my_lv my_vg -wi-a----- 10.00g格式化並掛載使用
[[email protected] ~]# mkdir /LVM #首先建立一個掛載點
[[email protected] ~]#
[[email protected] ~]# mkfs.ext4 /dev/my_vg/my_lv #格式化LVM分割槽
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
655360 inodes, 2621440 blocks
131072 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2151677952
80 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
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
[[email protected] ~]# mount /dev/my_vg/my_lv /LVM/ #掛載LVM
[[email protected] ~]#
[[email protected] ~]# df -h #檢視結果
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 5% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/mapper/my_vg-my_lv 9.8G 37M 9.2G 1% /LVM ← 掛載成功
◆LV 容量增加 (將LV的容量增加5G的空間)◆
注意：這裡擴充套件,要先擴充套件LVM,然後再擴充套件檔案系統
[[email protected] ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 5% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/mapper/my_vg-my_lv 9.8G 37M 9.2G 1% /LVM ←此處是10G
[[email protected] ~]# lvextend -L +5G /dev/my_vg/my_lv #執行增加命令,從VG卷組劃分5G
Size of logical volume my_vg/my_lv changed from 10.00 GiB (2560 extents) to 15.00 GiB (3840).
Logical volume my_vg/my_lv successfully resized.
[[email protected] ~]# resize2fs -f /dev/my_vg/my_lv #擴充套件檔案系統
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/my_vg/my_lv is mounted on /LVM; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 2
The filesystem on /dev/my_vg/my_lv is now 3932160 blocks long.
[[email protected] ~]# df -h #驗證擴充套件結果
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 5% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/mapper/my_vg-my_lv 15G 41M 14G 1% /LVM ←此處已經從10G 增加到15G◆LV 容量縮小(將LV的容量縮小5G的空間)◆
注意：這裡縮小,要解除安裝檔案系統,檢查分割槽,然後縮小檔案系統,最後再縮小LVM
[[email protected] ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 5% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/mapper/my_vg-my_lv 15G 41M 14G 1% /LVM ←此處顯示15G空間
[[email protected] ~]# umount /dev/my_vg/my_lv #解除安裝LVM卷組
[[email protected] ~]# e2fsck -f /dev/my_vg/my_lv #檢查檔案系統
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
/dev/my_vg/my_lv: 11/983040 files (0.0% non-contiguous), 104724/3932160 blocks
[[email protected] ~]# resize2fs -f /dev/my_vg/my_lv 10G(減小後的大小) #縮小檔案系統
resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/my_vg/my_lv to 2621440 (4k) blocks.
The filesystem on /dev/my_vg/my_lv is now 2621440 blocks long.
[[email protected] ~]# lvreduce -L 10G /dev/my_vg/my_lv #縮小LVM
WARNING: Reducing active logical volume to 10.00 GiB.
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce my_vg/my_lv? [y/n]: y #輸入y
Size of logical volume my_vg/my_lv changed from 15.00 GiB (3840 extents) to 10.00 GiB (2560).
Logical volume my_vg/my_lv successfully resized.
[[email protected] ~]# mount /dev/my_vg/my_lv /LVM/ #掛載
[[email protected] ~]# df -h #再次檢視分割槽變化
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
tmpfs 110M 0 110M 0% /dev/shm
tmpfs 110M 5.5M 104M 5% /run
tmpfs 110M 0 110M 0% /sys/fs/cgroup
/dev/sda1 1014M 130M 885M 13% /boot
tmpfs 22M 0 22M 0% /run/user/0
/dev/mapper/my_vg-my_lv 9.8G 37M 9.2G 1% /LVM ←此處已經從15G變成10G◆LV 快照功能◆
拍攝快照
lvcreate [-s 快照] -n [快照名] -L [快照大小] [指定分割槽]
[[email protected] LVM]# ls
1 12 16 2 23 27 30 34 38 41 45 49 52 56 6 63 67 70 74 78 81 85 89 92 96
10 13 17 20 24 28 31 35 39 42 46 5 53 57 60 64 68 71 75 79 82 86 9 93 97
100 14 18 21 25 29 32 36 4 43 47 50 54 58 61 65 69 72 76 8 83 87 90 94 98
11 15 19 22 26 3 33 37 40 44 48 51 55 59 62 66 7 73 77 80 84 88 91 95 99
[[email protected] LVM]# lvcreate -s -n mylv_back -L 200M /dev/my_vg/my_lv #給/LVM目錄拍攝快照
Logical volume "mylv_back" created.
[[email protected] LVM]# lvs #檢視快照
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
root centos -wi-ao---- <8.00g
swap centos -wi-ao---- 1.00g
my_lv my_vg owi-aos--- 10.00g
mylv_back my_vg swi-a-s--- 200.00m my_lv 0.01 ←此處就是快照快照恢復
[[email protected] LVM]# ls
1 12 16 2 23 27 30 34 38 41 45 49 52 56 6 63 67 70 74 78 81 85 89 92 96
10 13 17 20 24 28 31 35 39 42 46 5 53 57 60 64 68 71 75 79 82 86 9 93 97
100 14 18 21 25 29 32 36 4 43 47 50 54 58 61 65 69 72 76 8 83 87 90 94 98
11 15 19 22 26 3 33 37 40 44 48 51 55 59 62 66 7 73 77 80 84 88 91 95 99
[[email protected] LVM]# rm -fr * #模擬被刪除
[[email protected] LVM]# mkdir /back #建立掛載點
[[email protected] LVM]# mount /dev/my_vg/mylv_back /back/ #掛載備份檔案
[[email protected] LVM]# cp -a /back/* ./ #複製備份檔案
[[email protected] LVM]# ls
1 12 16 2 23 27 30 34 38 41 45 49 52 56 6 63 67 70 74 78 81 85 89 92 96
10 13 17 20 24 28 31 35 39 42 46 5 53 57 60 64 68 71 75 79 82 86 9 93 97
100 14 18 21 25 29 32 36 4 43 47 50 54 58 61 65 69 72 76 8 83 87 90 94 98
11 15 19 22 26 3 33 37 40 44 48 51 55 59 62 66 7 73 77 80 84 88 91 95 99RAID 獨立磁碟冗餘陣列
定義：獨立磁碟構成的具有冗餘能力的陣列
磁碟陣列分類：一是外接式磁碟陣列櫃、二是內接式磁碟陣列卡，三是利用軟體來模擬
1.通過把多個磁碟組織在一起作為一個邏輯卷提供磁碟跨越功能
2.通過把資料分成多個數據塊（Block）並行寫入/讀出多個磁碟以提高訪問磁碟的速度
3.通過映象或校驗操作提供容錯能力
注意：RAID磁碟陣列主要為了保證硬體損壞的情況下業務不會終止，無法防止誤操作
磁碟陣列的分類
1.外接式磁碟陣列櫃
2.內接式磁碟陣列
3.利用軟體來模擬
注意：通常情況下,生產環境中,一般使用硬體RAID來做,這裡只做瞭解即可
RAID磁碟陣列簡介
RAID 0 沒有奇偶校驗的 (條帶卷)
RAID 0 提高儲存效能的原理是把連續的資料分散到多個磁碟上存取,這樣系統有資料請求就可以被多個磁碟並行的執行,每個磁碟執行屬於它自己的那部分資料請求
RAID 1 獨立磁碟冗餘陣 (映象卷)
RAID 1 通過磁碟資料映象實現資料冗餘,在成對的獨立磁碟上產生互為備份的資料.當原始資料繁忙時,可直接從映象拷貝中讀取資料,因此RAID 1可以提高讀取效能.
RAID10 (鏡象陣列條帶)
Raid 10 是一個Raid1與Raid0的組合體,它是利用奇偶校驗實現條帶集映象,所以它繼承了Raid0的快速和Raid1的安全.
RAID5 分散式奇偶校驗的獨立磁碟結構(最少3塊)
RAID 5 是一種儲存效能,資料安全,和儲存成本,兼顧的儲存解決方案. RAID 5可以理解為是RAID 0和RAID 1的折中方案.
◆Mdadm 命令解析◆
[[email protected] ~]# mdadm --help
mdadm is used for building, managing, and monitoring
Linux md devices (aka RAID arrays)
Usage: mdadm
mdadm --create --auto=yes /dev/md[0-9] --raid-devices=[0-n] \
--level=[015] --spare-devices=[0-n] /dev/sd[a-z]
--create #新建RAID引數
--auto=yes #預設配置
--raid-devices=N #磁碟陣列數
--spare-devices=N #備份磁碟數
--level [015] #陣列等級
mdadm --detail #查詢陣列資訊◆構建一個RAID 5◆
注意：精簡模式下,沒有安裝此命令,執行 yum install -y mdadm 安裝
[[email protected] ~]# ls -l /dev/sd[b-z]
brw-rw---- 1 root disk 8, 16 Sep 21 23:06 /dev/sdb
brw-rw---- 1 root disk 8, 32 Sep 21 23:06 /dev/sdc
brw-rw---- 1 root disk 8, 48 Sep 21 23:06 /dev/sdd
brw-rw---- 1 root disk 8, 64 Sep 21 23:04 /dev/sde
[[email protected] ~]# mdadm --create --auto=yes /dev/md0 --level=5 \
> --raid-devices=3 --spare-devices=1 /dev/sd{b,c,d,e} #建立一個RAID,其中介面是/dev/md0,等級是RAID5
mdadm: Defaulting to version 1.2 metadata #主磁碟數3,備份盤數1,提供sd{b,c,d,e}磁碟
mdadm: array /dev/md0 started.
[[email protected] ~]# mdadm --detail /dev/md0 #檢視陣列資訊
/dev/md0: ←裝置檔名
Version : 1.2
Creation Time : Fri Sep 21 23:19:09 2018 ←建立日期
Raid Level : raid5 ←RAID等級
Array Size : 20953088 (19.98 GiB 21.46 GB) ←可用空間
Used Dev Size : 10476544 (9.99 GiB 10.73 GB) ←每個裝置可用空間
Raid Devices : 3 ←RAID裝置數量
Total Devices : 4 ←全部裝置數量
Persistence : Superblock is persistent
Update Time : Fri Sep 21 23:19:26 2018
State : clean, degraded, recovering
Active Devices : 3 ←啟動磁碟
Working Devices : 4 ←可用磁碟
Failed Devices : 0 ←錯誤磁碟
Spare Devices : 1 ←預備磁碟
Layout : left-symmetric
Chunk Size : 512K
Consistency Policy : resync
Rebuild Status : 34% complete
Name : localhost.localdomain:0 (local to host localhost.localdomain)
UUID : 2ee2bcd5:c5189354:d3810252:23c2d5a8 ←此裝置UUID
Events : 6
Number Major Minor RaidDevice State
0 8 16 0 active sync /dev/sdb
1 8 32 1 active sync /dev/sdc
4 8 48 2 spare rebuilding /dev/sdd
3 8 64 - spare /dev/sde格式化 /dev/md0並掛載使用
[[email protected] ~]# mkfs -t ext4 /dev/md0 #格式化
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=128 blocks, Stripe width=256 blocks
1310720 inodes, 5238272 blocks
261913 blocks (5.00%) 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
[[email protected] ~]# mkdir /RAID #新建掛載目錄
[[email protected] ~]#
[[email protected] ~]# mount /dev/md0 /RAID/ #掛載裝置
[[email protected] ~]#
[[email protected] ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 8.0G 1.2G 6.9G 15% /
devtmpfs 98M 0 98M 0% /dev
/dev/sr0 4.2G 4.2G 0 100% /mnt
/dev/md0 20G 45M 19G 1% /RAID ←此處可看到掛載成功◆RAID 模擬救援模式◆
mdadm --manage /dev/md[0-9] --add 裝置 --remove 裝置 --fail 裝置
--add #將後面的裝置加入md中
--remove #移除裝置
--fail #設定出錯磁碟
------------------------------------------------------------
[實驗]
[[email protected] /]# mdadm --manage /dev/md0 --fail /dev/sdb #將/dev/sdb標註為錯誤
mdadm: set /dev/sdb faulty in /dev/md0
[[email protected] /]# mdadm --detail /dev/md0 #檢視一下狀態
/dev/md0:
Version : 1.2
Creation Time : Fri Sep 21 23:19:09 2018
Raid Level : raid5
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 10476544 (9.99 GiB 10.73 GB)
Raid Devices : 3
Total Devices : 4
Persistence : Superblock is persistent
Update Time : Fri Sep 21 23:50:12 2018
State : clean, degraded, recovering
Active Devices : 2
Working Devices : 3
Failed Devices : 1 ← 出錯磁碟一個
Spare Devices : 1
Layout : left-symmetric
Chunk Size : 512K
Consistency Policy : resync
Rebuild Status : 5% complete ←此處需要注意,他正在恢復資料,等到100%時又可以正常工作
Name : localhost.localdomain:0 (local to host localhost.localdomain)
UUID : 2ee2bcd5:c5189354:d3810252:23c2d5a8
Events : 20
Number Major Minor RaidDevice State
3 8 64 0 spare rebuilding /dev/sde
1 8 32 1 active sync /dev/sdc
4 8 48 2 active sync /dev/sdd
0 8 16 - faulty /dev/sdb ← 出錯磁碟
[[email protected] /]# mdadm --manage /dev/md0 --remove /dev/sdb #移除這個壞掉的磁碟
mdadm: hot removed /dev/sdb from /dev/md0
[[email protected] /]# mdadm --manage /dev/md0 --add /dev/sdb #新增一個新的磁碟
mdadm: added /dev/sdb