Raid 獨立磁碟冗餘陣列
2023-06-18 18:00:20
Raid儲存的實現
概念：
RAID （ Redundant Array of Independent Disks ）即獨立磁碟冗餘陣列，簡稱為「磁碟陣列」，其實就是用多個獨立的磁碟組成在一起形成一個大的磁碟系統，從而實現比單塊磁碟更好的儲存效能和更高的可靠性。
種類：
Raid 0：至少需要兩塊硬碟，磁碟越多，讀寫速度越快，沒有冗餘。
Raid 1：只能用兩塊硬碟，兩塊硬碟的資料互為映象(寫慢，讀快)，一塊磁碟冗餘。
Raid 5：至少需要3塊硬碟，一塊磁碟冗餘。它是最通行的設定方式。具有奇偶校驗的資料恢復功能的資料存貯方式。奇偶校驗資料塊分佈於陣列裡的各個硬碟中。
Raid 6：至少需要4塊硬碟，2塊磁碟冗餘,硬碟的總數大於等於4即可。
Raid 10：至少需要4塊硬碟，冗餘一半的硬碟數量，但是硬碟的總數必須是大於或等於4的偶數（相當於每兩塊硬碟做一個Raid0，然後把各個Raid0做成一個Raid1）。
Raid 50：至少需要6塊硬碟，磁碟的冗餘相當於每三個硬碟做了一個Raid5，然後，每個Raid5又組合成了Raid0（Raid5中有一個硬碟冗餘，即使壞了也不會破壞Raid0），所以，Raid50的磁碟的 冗餘硬碟數量=磁碟總數÷3 。
Raid 60：至少需要8塊硬碟
raid 0的建立
RAID0 是一種非常簡單的的方式，它將多塊磁碟組合在一起形成一個大容量的儲存。當我們要寫資料的時候，會將資料分為N份，以獨立的方式實現N塊磁碟的讀寫，那麼這N份資料會同時並行的寫到磁碟中，因此執行效能非常的高。RAID0 的讀寫效能理論上是單塊磁碟的N倍（僅限理論，因為實際中磁碟的定址時間也是效能佔用的大頭）
但RAID0的問題是，它並不提供資料校驗或冗餘備份，因此一旦某塊磁碟損壞了，資料就直接丟失，無法恢復了。因此RAID0就不可能用於高要求的業務中，但可以用在對可靠性要求不高，對讀寫效能要求高的場景中。
新增4塊硬碟，每塊50G
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顯示
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命令檢視
[root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 50G 0 disk sdc 8:32 0 50G 0 disk sdd 8:48 0 50G 0 disk sde 8:64 0 50G 0 disk sr0 11:0 1 4.2G 0 rom -
下載mdadm命令
#檢索 [root@localhost ~]# yum provides *bin/mdadm Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.cqu.edu.cn * extras: mirrors.cqu.edu.cn * updates: mirrors.cqu.edu.cn base | 3.6 kB 00:00:00 extras | 2.9 kB 00:00:00 updates | 2.9 kB 00:00:00 updates/7/x86_64/primary_db | 20 MB 00:00:07 mdadm-4.1-6.el7.x86_64 : The mdadm program controls Linux md devices (software RAID arrays) Repo : base Matched from: Filename : /usr/sbin/mdadm updates/7/x86_64/filelists_db | 11 MB 00:00:04 mdadm-4.1-7.el7_9.x86_64 : The mdadm program controls Linux md devices (software RAID arrays) Repo : updates Matched from: Filename : /usr/sbin/mdadm mdadm-4.1-8.el7_9.x86_64 : The mdadm program controls Linux md devices (software RAID arrays) Repo : updates Matched from: Filename : /usr/sbin/mdadm mdadm-4.1-9.el7_9.x86_64 : The mdadm program controls Linux md devices (software RAID arrays) Repo : updates Matched from: Filename : /usr/sbin/mdadm #安裝 [root@localhost ~]# yum -y install mdadm Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.cqu.edu.cn * extras: mirrors.cqu.edu.cn * updates: mirrors.cqu.edu.cn Resolving Dependencies --> Running transaction check ---> Package mdadm.x86_64 0:4.1-9.el7_9 will be installed --> Processing Dependency: libreport-filesystem for package: mdadm-4.1-9.el7_9.x86_64 --> Running transaction check ...... -
用兩塊磁碟建立raid 0
[root@localhost ~]# mdadm --create /dev/md0 --level 0 --raid-device 2 /dev/sd{b,c} mdadm: Fail to create md0 when using /sys/module/md_mod/parameters/new_array, fallback to creation via node mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md0 started. [root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 50G 0 disk └─md0 9:0 0 100G 0 raid0 sdc 8:32 0 50G 0 disk └─md0 9:0 0 100G 0 raid0 sdd 8:48 0 50G 0 disk sde 8:64 0 50G 0 disk sr0 11:0 1 4.2G 0 rom -
格式化md0，並掛載
#格式化 [root@localhost ~]# mkfs.xfs /dev/md0 meta-data=/dev/md0 isize=512 agcount=16, agsize=1637248 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=26195968, imaxpct=25 = sunit=128 swidth=256 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=12792, version=2 = sectsz=512 sunit=8 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 #掛載 [root@localhost ~]# mkdir /raid0 [root@localhost ~]# mount /dev/md0 /raid0 [root@localhost ~]# df -hT Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 14G 37G 28% / devtmpfs devtmpfs 3.8G 0 3.8G 0% /dev tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs tmpfs 3.9G 12M 3.8G 1% /run tmpfs tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 142M 873M 14% /boot tmpfs tmpfs 781M 0 781M 0% /run/user/0 /dev/md0 xfs 100G 33M 100G 1% /raid0 -
新增到開機自啟動組態檔裡面
[root@localhost ~]# blkid /dev/md0 /dev/md0: UUID="cc930653-5ab7-43a0-87e4-6906c3d1bd98" TYPE="xfs" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID=cc930653-5ab7-43a0-87e4-6906c3d1bd98 /raid0 xfs defaults 0 0
raid 1的建立
RAID1 是磁碟陣列中單位成本最高的一種方式。因為它的原理是在往磁碟寫資料的時候，將同一份資料無差別的寫兩份到磁碟，分別寫到工作磁碟和映象磁碟，那麼它的實際空間使用率只有50%了，兩塊磁碟當做一塊用，這是一種比較昂貴的方案。
RAID1其實與RAID0效果剛好相反。RAID1 這種寫雙份的做法，就給資料做了一個冗餘備份。這樣的話，任何一塊磁碟損壞了，都可以再基於另外一塊磁碟去恢復資料，資料的可靠性非常強，但效能就沒那麼好了。
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兩塊磁碟建立raid 1
[root@localhost ~]# mdadm --create /dev/md1 --level 1 --raid-device 2 /dev/sd{e,f} mdadm: Note: this array has metadata at the start and may not be suitable as a boot device. If you plan to store '/boot' on this device please ensure that your boot-loader understands md/v1.x metadata, or use --metadata=0.90 mdadm: cannot open /dev/sdf: No such file or directory [root@localhost ~]# mdadm --create /dev/md1 --level 1 --raid-device 2 /dev/sd{d,e} mdadm: Note: this array has metadata at the start and may not be suitable as a boot device. If you plan to store '/boot' on this device please ensure that your boot-loader understands md/v1.x metadata, or use --metadata=0.90 Continue creating array? y mdadm: Fail to create md1 when using /sys/module/md_mod/parameters/new_array, fallback to creation via node mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md1 started. -
檢視，並格式化掛載
#檢視 [root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 50G 0 disk └─md0 9:0 0 100G 0 raid0 sdc 8:32 0 50G 0 disk └─md0 9:0 0 100G 0 raid0 sdd 8:48 0 50G 0 disk └─md1 9:1 0 50G 0 raid1 sde 8:64 0 50G 0 disk └─md1 9:1 0 50G 0 raid1 sr0 11:0 1 4.2G 0 rom #格式化 [root@localhost ~]# mkfs.xfs /dev/md1 meta-data=/dev/md1 isize=512 agcount=4, agsize=3274688 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=13098752, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=6395, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 #掛載 [root@localhost ~]# mkdir /raid1 [root@localhost ~]# mount /dev/md1 /raid1 [root@localhost ~]# df -hT Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 14G 37G 28% / devtmpfs devtmpfs 3.8G 0 3.8G 0% /dev tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs tmpfs 3.9G 12M 3.8G 1% /run tmpfs tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 142M 873M 14% /boot tmpfs tmpfs 781M 0 781M 0% /run/user/0 /dev/md1 xfs 50G 33M 50G 1% /raid1 -
新增到開機自啟動組態檔裡
[root@localhost ~]# umount /raid1 [root@localhost ~]# blkid /dev/md1 /dev/md1: UUID="401222a9-5c23-47cb-936a-aa03101cbb1a" TYPE="xfs" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID=401222a9-5c23-47cb-936a-aa03101cbb1a /raid1 xfs defaults 0 0
raid 5的建立
RAID 5是目前用的最多的一種方式。因為 RAID5 是一種將 儲存效能、資料安全、儲存成本 兼顧的一種方案。RAID5模式中，不再需要用單獨的磁碟寫校驗碼了。它把校驗碼資訊分佈到各個磁碟上。例如，總共有N塊磁碟，那麼會將要寫入的資料分成N份，並行的寫入到N塊磁碟中，同時還將資料的校驗碼資訊也寫入到這N塊磁碟中（資料與對應的校驗碼資訊必須得分開儲存在不同的磁碟上）。一旦某一塊磁碟損壞了，就可以用剩下的資料和對應的奇偶校驗碼資訊去恢復損壞的資料。
RAID5校驗位演演算法原理：P = D1 xor D2 xor D3 … xor Dn （D1,D2,D3 … Dn為資料塊，P為校驗，xor為互斥或運算）
RAID5的方式，最少需要三塊磁碟來組建磁碟陣列，允許最多同時壞一塊磁碟。如果有兩塊磁碟同時損壞了，那資料就無法恢復了。
新增3塊硬碟，每塊20G
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顯示
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檢視
[root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 20G 0 disk sdc 8:32 0 20G 0 disk sdd 8:48 0 20G 0 disk -
建立raid 5
[root@localhost ~]# mdadm --create /dev/md5 --raid-device 3 /dev/sd{b,c,d} mdadm: a RAID level is needed to create an array. [root@localhost ~]# mdadm --create /dev/md5 --level 5 --raid-device 3 /dev/sd{b,c,d} mdadm: Fail to create md5 when using /sys/module/md_mod/parameters/new_array, fallback to creation via node mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md5 started. [root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 20G 0 disk └─md5 9:5 0 40G 0 raid5 sdc 8:32 0 20G 0 disk └─md5 9:5 0 40G 0 raid5 sdd 8:48 0 20G 0 disk └─md5 9:5 0 40G 0 raid5 -
格式化掛載
#格式化 [root@localhost ~]# mkfs.xfs /dev/md5 meta-data=/dev/md5 isize=512 agcount=16, agsize=654720 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=10475520, imaxpct=25 = sunit=128 swidth=256 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=5120, version=2 = sectsz=512 sunit=8 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 #掛載 [root@localhost ~]# df -hT Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 14G 37G 28% / devtmpfs devtmpfs 3.8G 0 3.8G 0% /dev tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs tmpfs 3.9G 12M 3.8G 1% /run tmpfs tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 142M 873M 14% /boot tmpfs tmpfs 781M 0 781M 0% /run/user/0 /dev/md5 xfs 40G 33M 40G 1% /raid5 -
新增到開機自啟動組態檔裡
[root@localhost ~]# blkid /dev/md5 /dev/md5: UUID="0d4231a6-6c05-4c89-a489-671cf062c966" TYPE="xfs" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID=0d4231a6-6c05-4c89-a489-671cf062c966 /raid5 xfs defaults 0 0
raid 10的建立
RAID10兼備了RAID1和RAID0的有優點。首先基於RAID1模式將磁碟分為2份，當要寫入資料的時候，將所有的資料在兩份磁碟上同時寫入，相當於寫了雙份資料，起到了資料保障的作用。且在每一份磁碟上又會基於RAID0技術講資料分為N份並行的讀寫，這樣也保障了資料的效率。
但也可以看出RAID10模式是有一半的磁碟空間用於儲存冗餘資料的，浪費的很嚴重，因此用的也不是很多。
新增4塊硬碟，每塊100G
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顯示
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檢視
[root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 100G 0 disk sdc 8:32 0 100G 0 disk sdd 8:48 0 100G 0 disk sde 8:64 0 100G 0 disk sr0 11:0 1 4.2G 0 rom -
建立raid 10
[root@localhost ~]# mdadm --create /dev/md10 --level 10 --raid-device 4 /dev/sd{b,c,d,e} mdadm: Fail to create md10 when using /sys/module/md_mod/parameters/new_array, fallback to creation via node mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md10 started. [root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 100G 0 disk └─md10 9:10 0 199.9G 0 raid10 sdc 8:32 0 100G 0 disk └─md10 9:10 0 199.9G 0 raid10 sdd 8:48 0 100G 0 disk └─md10 9:10 0 199.9G 0 raid10 sde 8:64 0 100G 0 disk └─md10 9:10 0 199.9G 0 raid10 sr0 11:0 1 4.2G 0 rom -
磁碟格式化並掛載
#格式化 [root@localhost ~]# mkfs.xfs /dev/md10 meta-data=/dev/md10 isize=512 agcount=16, agsize=3274624 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=52393984, imaxpct=25 = sunit=128 swidth=256 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=25584, version=2 = sectsz=512 sunit=8 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 #掛載 [root@localhost ~]# mkdir /raid10 [root@localhost ~]# mount /dev/md10 /raid10 [root@localhost ~]# df -hT Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 14G 37G 28% / devtmpfs devtmpfs 3.8G 0 3.8G 0% /dev tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs tmpfs 3.9G 12M 3.8G 1% /run tmpfs tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 142M 873M 14% /boot tmpfs tmpfs 781M 0 781M 0% /run/user/0 /dev/md10 xfs 200G 33M 200G 1% /raid10 -
新增到開機自啟動組態檔裡
[root@localhost ~]# blkid /dev/md10 /dev/md10: UUID="c57bbd24-efc0-4521-a4d7-a870f012c430" TYPE="xfs" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID=c57bbd24-efc0-4521-a4d7-a870f012c430 /raid10 xfs defaults 0 0
磁碟分割區，格式化，掛載
分割區
新增一塊2T磁碟
檢視所有磁碟情況
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命令：
[root@localhost ~]# fdisk -l Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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 /dev/sda: 214.7 GB, 214748364800 bytes, 419430400 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: 0x00097353 Device Boot Start End Blocks Id System /dev/sda1 * 2048 2099199 1048576 83 Linux /dev/sda2 2099200 419430399 208665600 8e Linux LVM Disk /dev/mapper/centos-root: 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 /dev/mapper/centos-swap: 8455 MB, 8455716864 bytes, 16515072 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 /dev/mapper/centos-home: 151.5 GB, 151523426304 bytes, 295944192 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
分割區開始
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內容為1個primary分割區,1個exetended分割區,3個logical分割區
#建立主分割區 Command (m for help): p Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0xb65bdaed Device Boot Start End Blocks Id System Command (m for help): n Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): Using default response p Partition number (1-4, default 1): First sector (2048-4194303999, default 2048): Using default value 2048 Last sector, +sectors or +size{K,M,G} (2048-4194303999, default 4194303999): +10G Partition 1 of type Linux and of size 10 GiB is set Command (m for help): p Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0xb65bdaed Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux #建立擴充套件分割區 Command (m for help): n Partition type: p primary (1 primary, 0 extended, 3 free) e extended Select (default p): e Partition number (2-4, default 2): First sector (20973568-4194303999, default 20973568): Using default value 20973568 Last sector, +sectors or +size{K,M,G} (20973568-4194303999, default 4194303999): Using default value 4194303999 Partition 2 of type Extended and of size 2 TiB is set Command (m for help): p Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0xb65bdaed Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 4194303999 2086665216 5 Extended #建立3個邏輯分割區 Command (m for help): n Partition type: p primary (1 primary, 1 extended, 2 free) l logical (numbered from 5) Select (default p): l Adding logical partition 5 First sector (20975616-4194303999, default 20975616): Using default value 20975616 Last sector, +sectors or +size{K,M,G} (20975616-4194303999, default 4194303999): +20G Partition 5 of type Linux and of size 20 GiB is set Command (m for help): n Partition type: p primary (1 primary, 1 extended, 2 free) l logical (numbered from 5) Select (default p): l Adding logical partition 6 First sector (62920704-4194303999, default 62920704): Using default value 62920704 Last sector, +sectors or +size{K,M,G} (62920704-4194303999, default 4194303999): +30G Partition 6 of type Linux and of size 30 GiB is set Command (m for help): p Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0x10285311 Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 4194303999 2086665216 5 Extended /dev/sdb5 20975616 62918655 20971520 83 Linux /dev/sdb6 62920704 125835263 31457280 83 Linux Command (m for help): n Partition type: p primary (1 primary, 1 extended, 2 free) l logical (numbered from 5) Select (default p): l Adding logical partition 7 First sector (125837312-4194303999, default 125837312): Using default value 125837312 Last sector, +sectors or +size{K,M,G} (125837312-4194303999, default 4194303999): +50G Partition 7 of type Linux and of size 50 GiB is set Command (m for help): p Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0x10285311 Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 4194303999 2086665216 5 Extended /dev/sdb5 20975616 62918655 20971520 83 Linux /dev/sdb6 62920704 125835263 31457280 83 Linux /dev/sdb7 125837312 230694911 52428800 83 Linux
分割區結束儲存退出
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命令：
#w儲存退出 Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. Syncing disks. #重新整理磁碟 [root@localhost ~]# partprobe Warning: Unable to open /dev/sr0 read-write (Read-only file system). /dev/sr0 has been opened read-only. -
檢視
[root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─centos-root 253:0 0 50G 0 lvm / ├─centos-swap 253:1 0 7.9G 0 lvm [SWAP] └─centos-home 253:2 0 141.1G 0 lvm sdb 8:16 0 2T 0 disk ├─sdb1 8:17 0 10G 0 part ├─sdb2 8:18 0 1K 0 part ├─sdb5 8:21 0 20G 0 part ├─sdb6 8:22 0 30G 0 part └─sdb7 8:23 0 50G 0 part sr0 11:0 1 4.2G 0 rom [root@localhost ~]# fdisk -l Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0xe4f035bc Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 4194303999 2086665216 5 Extended /dev/sdb5 20975616 62918655 20971520 83 Linux /dev/sdb6 62920704 125835263 31457280 83 Linux /dev/sdb7 125837312 230694911 52428800 83 Linux
格式化與掛載
取分割區的磁碟進行格式化
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命令：
#設定/dev/sdb6的檔案格式為xfs [root@localhost ~]# mkfs.xfs /dev/sdb6 meta-data=/dev/sdb6 isize=512 agcount=4, agsize=1966080 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=7864320, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=3840, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 #將sdb6掛載到mnt資料夾 [root@localhost ~]# mount /dev/sdb6 /mnt [root@localhost ~]# df -hT Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 14G 37G 28% / devtmpfs devtmpfs 3.8G 0 3.8G 0% /dev tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs tmpfs 3.9G 12M 3.8G 1% /run tmpfs tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 142M 873M 14% /boot tmpfs tmpfs 781M 0 781M 0% /run/user/0 /dev/sdb6 xfs 30G 33M 30G 1% /mnt #設定開機自啟動掛載 [root@localhost ~]# blkid /dev/sdb6 /dev/sdb6: UUID="57eb7bba-cc7a-4f6c-99bf-bccb067d266f" TYPE="xfs" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID="57eb7bba-cc7a-4f6c-99bf-bccb067d266f" /mnt xfs defaults 0 0
利用磁碟建立swap分割區
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更改磁碟id為swap
#更改/dev/sdb7的id為82 [root@localhost ~]# fdisk /dev/sdb Command (m for help): t Partition number (1,2,5-7, default 7): 7 Hex code (type L to list all codes): 82 Changed type of partition 'Linux' to 'Linux swap / Solaris' Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8) Syncing disks. [root@localhost ~]# partprobe Warning: Unable to open /dev/sr0 read-write (Read-only file system). /dev/sr0 has been opened read-only. [root@localhost ~]# fdisk -l Disk /dev/sdb: 2147.5 GB, 2147483648000 bytes, 4194304000 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: 0xe4f035bc Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 4194303999 2086665216 5 Extended /dev/sdb5 20975616 62918655 20971520 83 Linux /dev/sdb6 62920704 125835263 31457280 83 Linux /dev/sdb7 125837312 230694911 52428800 82 Linux swap / Solaris -
格式化
[root@localhost ~]# mkswap /dev/sdb7 Setting up swapspace version 1, size = 52428796 KiB no label, UUID=a48e154b-4da3-4771-9e09-8a357aa6049b -
掛載到swap分割區
#檢視swap分割區有7G [root@localhost ~]# free -h total used free shared buff/cache available Mem: 7.6G 181M 7.2G 11M 295M 7.2G Swap: 7.9G 0B 7.9G #新增/dev/sdb7後 [root@localhost ~]# swapon /dev/sdb7 [root@localhost ~]# free -h total used free shared buff/cache available Mem: 7.6G 221M 7.1G 11M 295M 7.1G Swap: 57G 0B 57G -
實現自動掛載
[root@localhost ~]# blkid /dev/sdb7 /dev/sdb7: UUID="6c77c8f6-9b57-4def-9885-d92a45b7abe4" TYPE="swap" [root@localhost ~]# vi /etc/fstab /dev/mapper/centos-root / xfs defaults 0 0 UUID=60defebd-6b85-43da-b5ce-1977bac72048 /boot xfs defaults 0 0 #/dev/mapper/centos-home /home xfs defaults 0 0 /dev/mapper/centos-swap swap swap defaults 0 0 UUID="6c77c8f6-9b57-4def-9885-d92a45b7abe4" swap swap defaults 0 0