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產生邏輯捲軸

何謂LVM？ LVM (Logical Volume Manager)：邏輯捲軸管理員。 LVM 目的為彈性進行 filesystem 的擴充或縮小。 PV, PE, VG, LV 的意義 Physical Volume, PV, 實體捲軸：partition 時需要調整系統識別碼 (system ID) 成為 8e (LVM 的識別碼)。 Volume Group, VG, 捲軸群組：將許多 PV 整合而成。 Physical Extend, PE, 實體延伸區塊：LVM 最小的儲存區塊。 Logical Volume, LV, 邏輯捲軸：從 VG 切割而成，為最後可被格式化使用之格式，LV 的裝置檔名通常指定為『 /dev/vgname/lvname 』的樣式。建立 LVM partitions [root@instructor ~]# fdisk -c /dev/sda Command (m for help): p Disk /dev/sda: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2bd2c32a Device Boot Start End Blocks Id System /dev/sda1 * 1 17 131072 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 17 4096 32768000 8e Linux LVM /dev/sda3 4096 6646 20480000 8e Linux LVM /dev/sda4 6646 60802 435006464 5 Extended /dev/sda5 6646 7952 10485760 83 Linux /dev/sda6 7952 10563 20979362 8e Linux LVM /dev/sda7 10564 11869 10490413+ 8e Linux LVM Command (m for help): n First cylinder (11870-60802, default 11870): Using default value 11870 Last cylinder, +cylinders or +size{K,M,G} (11870-60802, default 60802): +1G Command (m for help): n First cylinder (12002-60802, default 12002): Using default value 12002 Last cylinder, +cylinders or +size{K,M,G} (12002-60802, default 60802): +1G Command (m for help): p Disk /dev/sda: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2bd2c32a Device Boot Start End Blocks Id System /dev/sda1 * 1 17 131072 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 17 4096 32768000 8e Linux LVM /dev/sda3 4096 6646 20480000 8e Linux LVM /dev/sda4 6646 60802 435006464 5 Extended /dev/sda5 6646 7952 10485760 83 Linux /dev/sda6 7952 10563 20979362 8e Linux LVM /dev/sda7 10564 11869 10490413+ 8e Linux LVM /dev/sda8 11870 12001 1060258+ 83 Linux /dev/sda9 12002 12133 1060258+ 83 Linux Command (m for help): t Partition number (1-10): 8 Hex code (type L to list codes): 8e Changed system type of partition 8 to 8e (Linux LVM) Command (m for help): t Partition number (1-10): 9 Hex code (type L to list codes): 8e Changed system type of partition 9 to 8e (Linux LVM) Command (m for help): p Disk /dev/sda: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2bd2c32a Device Boot Start End Blocks Id System /dev/sda1 * 1 17 131072 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 17 4096 32768000 8e Linux LVM /dev/sda3 4096 6646 20480000 8e Linux LVM /dev/sda4 6646 60802 435006464 5 Extended /dev/sda5 6646 7952 10485760 83 Linux /dev/sda6 7952 10563 20979362 8e Linux LVM /dev/sda7 10564 11869 10490413+ 8e Linux LVM /dev/sda8 11870 12001 1060258+ 8e Linux LVM /dev/sda9 12002 12133 1060258+ 8e Linux LVM 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@instructor ~]# partprobe Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (Device or resource busy). As a result, it may not reflect all of your changes until after reboot. device-mapper: remove ioctl failed: Device or resource busy device-mapper: remove ioctl failed: Device or resource busy Warning: parted was unable to re-read the partition table on /dev/mapper/GLSguest-demo-real (Device or resource busy). This means Linux won't know anything about the modifications you made. [root@instructor ~]# reboot [root@instructor ~]# fdisk -l /dev/sda Disk /dev/sda: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2bd2c32a Device Boot Start End Blocks Id System /dev/sda1 * 1 17 131072 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 17 4096 32768000 8e Linux LVM /dev/sda3 4096 6646 20480000 8e Linux LVM /dev/sda4 6646 60802 435006464 5 Extended /dev/sda5 6646 7952 10485760 83 Linux /dev/sda6 7952 10563 20979362 8e Linux LVM /dev/sda7 10564 11869 10490413+ 8e Linux LVM /dev/sda8 11870 12001 1060258+ 8e Linux LVM /dev/sda9 12002 12133 1060258+ 8e Linux LVM 產生 PV [root@instructor ~]# pvscan PV /dev/sda3 VG GLSguest lvm2 [19.50 GiB / 5.00 GiB free] PV /dev/sda2 VG GLSvg lvm2 [31.22 GiB / 0 free] PV /dev/sda6 VG GLSvg lvm2 [20.00 GiB / 6.44 GiB free] PV /dev/sda7 VG GLSvg lvm2 [10.00 GiB / 10.00 GiB free] Total: 4 [80.72 GiB] / in use: 4 [80.72 GiB] / in no VG: 0 [0 ] [root@instructor ~]# pvcreate /dev/sda{8,9,10} Physical volume "/dev/sda8" successfully created Physical volume "/dev/sda9" successfully created Physical volume "/dev/sda10" successfully created [root@instructor ~]# pvscan PV /dev/sda3 VG GLSguest lvm2 [19.50 GiB / 5.00 GiB free] PV /dev/sda2 VG GLSvg lvm2 [31.22 GiB / 0 free] PV /dev/sda6 VG GLSvg lvm2 [20.00 GiB / 6.44 GiB free] PV /dev/sda7 VG GLSvg lvm2 [10.00 GiB / 10.00 GiB free] PV /dev/sda8 lvm2 [1.01 GiB] PV /dev/sda9 lvm2 [1.01 GiB] PV /dev/sda10 lvm2 [2.01 GiB] Total: 7 [84.75 GiB] / in use: 4 [80.72 GiB] / in no VG: 3 [4.03 GiB] [root@instructor ~]# pvdisplay "/dev/sda8" is a new physical volume of "1.01 GiB" --- NEW Physical volume --- PV Name /dev/sda8 VG Name PV Size 1.01 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID oaj98p-1kMw-LdJh-57yS-zxEf-MX1m-31XoZr "/dev/sda9" is a new physical volume of "1.01 GiB" --- NEW Physical volume --- PV Name /dev/sda9 VG Name PV Size 1.01 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID iugncx-zGZr-CDt9-PIU3-jq5n-54ec-2KJjQR "/dev/sda10" is a new physical volume of "2.01 GiB" --- NEW Physical volume --- PV Name /dev/sda10 VG Name PV Size 2.01 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID Ko6qem-n1mm-YMLd-pDMl-Ee0z-PClw-DcEI9b 產生 VG [root@instructor ~]# vgcreate -s 32M dywvg /dev/sda{8,9} Volume group "dywvg" successfully created [root@instructor ~]# vgscan Reading all physical volumes. This may take a while... Found volume group "dywvg" using metadata type lvm2 Found volume group "GLSguest" using metadata type lvm2 Found volume group "GLSvg" using metadata type lvm2 [root@instructor ~]# pvscan PV /dev/sda8 VG dywvg lvm2 [1.00 GiB / 0 free] PV /dev/sda9 VG dywvg lvm2 [1.00 GiB / 736.00 MiB free] PV /dev/sda3 VG GLSguest lvm2 [19.50 GiB / 5.00 GiB free] PV /dev/sda2 VG GLSvg lvm2 [31.22 GiB / 0 free] PV /dev/sda6 VG GLSvg lvm2 [20.00 GiB / 6.44 GiB free] PV /dev/sda7 VG GLSvg lvm2 [10.00 GiB / 10.00 GiB free] PV /dev/sda10 lvm2 [2.01 GiB] Total: 7 [84.73 GiB] / in use: 6 [82.72 GiB] / in no VG: 1 [2.01 GiB] [root@instructor ~]# vgdisplay dywvg --- Volume group --- VG Name dywvg System ID Format lvm2 Metadata Areas 2 Metadata Sequence No 3 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 0 Max PV 0 Cur PV 2 Act PV 2 VG Size 2.00 GiB PE Size 32.00 MiB Total PE 64 Alloc PE / Size 50 / 1.56 GiB Free PE / Size 14 / 448.00 MiB VG UUID NK9GXl-AVxX-g5Vj-Xx0n-HtRD-a9YW-F5mu0W 產生 LV [root@instructor ~]# lvcreate -l 50 -n dywlv dywvg Logical volume "dywlv" created [root@instructor ~]# ll /dev/dywvg/dywlv lrwxrwxrwx. 1 root root 8 Jul 10 19:26 /dev/dywvg/dywlv -> ../dm-20 [root@instructor ~]# lvdisplay /dev/dywvg/dywlv --- Logical volume --- LV Name /dev/dywvg/dywlv VG Name dywvg LV UUID 0U1tft-9dii-XLEp-fNv4-kf1d-Vu5J-m2ZMYo LV Write Access read/write LV Status available # open 0 LV Size 1.56 GiB Current LE 50 Segments 2 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:20 建立檔案系統 [root@instructor ~]# mkfs.ext3 /dev/dywvg/dywlv mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 102544 inodes, 409600 blocks 20480 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=419430400 13 block groups 32768 blocks per group, 32768 fragments per group 7888 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912 Writing inode tables: done Creating journal (8192 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 26 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@instructor ~]# mkdir /mnt/dywlvm [root@instructor ~]# mount /dev/dywvg/dywlv /mnt/dywlvm [root@instructor ~]# df -h /mnt/dywlvm Filesystem 1K-blocks Used Available Use% Mounted on /dev/mapper/dywvg-dywlv 1.6G 35M 1.5G 3% /mnt/dywlvm 2015-04-13