UNIT5 managing flexible storage using Logical Volume Manager
1.LVM (soluble disk extension)
1). LVM Setup (device can be infinitely expanded, but file system support 18eb)
1. Divide the physical partition and change the partition ID to 8e
Pvs|pvdisplay vdb1,2/* Display PV
Vgs|vgdisplay Westos/* Display VG Group
Lvs|lvdisplay lv0/* Displays the LV used
Watch-n 1 \/* Monitoring
' echo ' ===pvinfo ' \
;p vs \
; echo "===vginfo" \
; VGS \
; echo "===lvinfo" \
; Lvs;df-h/mnt '
PVCREATE/DEV/VDB1/* Create PV partition
Vgcreate WESTOS/DEV/VDB1/* Create VG Group Westos
Lvcreate-l 100m-n lv0 westos/* Create Lv0
MKFS.EXT4/DEV/WESTOS/LV0/* Format system
mount/dev/westos/lv0/mnt/
2) Delete the LVM disk (uninstall first, then shrink the file system, reduce the device)
umount/mnt/
Mkfs.ext4/dev/westos/lv0/*XFS cannot be flexibly managed
E2fsck-f/dev/westos/lv0/* View File system usage
Resize2fs/dev/westos/lv0 550M
Lvreduce-l 550m/dev/westos/lv0/* Shrink 550M disk
PVMOVE/DEV/VDB1/DEV/VDB2/* Give the first disk something to a second disk
Vgreduce WESTOS/DEV/VDB1/* Remove the first disk from the group
PVREMOVE/DEV/VDB1/* Delete First disk
3) Error and resolution (reduce file system first, so disk error prone)
Lvreduce-l 100m/dev/westos/lv0 (reduced file system)
mount/dev/westos/lv0/mnt/(Mount)
Lvextend-l 200m/dev/westos/lv0 (Extended file system)
Resize2fs/dev/westos/lv0 (Increased use of disk partitions)
mount/dev/westos/lv0/mnt/
If you delete the partition you are using directly, you will also get an error
Pvcreate/dev/vdb1
Vgextend WESTOS/DEV/VDB1
Fdisk/dev/vdb
Partprobe
Vgreduce--removemissing Westos (Delete the file system of the deleted partition)
4) Disk Snapshot
Lvcreate-l 10m-n lv0-backup-s/dev/westos/lv0/* Creating a Snapshot
mount/dev/westos/lv0-backup/mnt/
umount/mnt/
Lvremove/dev/westos/lv0-backup/* Deleting a snapshot
Lvcreate-l 10m-n lv0-backup-s/dev/westos/lv0/* using the snapshot again
**2. Scripts for automatically creating partitions
#! /bin/bash
Fdisk/dev/vdb << End
N
+100m
Wq
End
3. How to restore the startup program when emptying the boot
DD If=/dev/zero Of=/dev/vda bs=446 count=1/* emptying the boot program
File:/run/media/kiosk/ca9c-5ce5/11.11/11.6 Page 3 of 3
Recover files with CD or PXE
Follow the steps to execute Enter,chroot
In the execution: Grub2-install/dev/vda
The second book unit5. Manage flexible storage with Logical Volume Manager