Good programmer Cloud Computing Learning Route sharing LVM Management details
Good programmer Cloud Computing Learning Route sharing LVM Management details
Online expansion of online
Data migration online
Creating a LVM LVM is called logical volume management
VG expand / shrink
LV capacity expansion
Expansion of file system, online expansion and single disk RAID0 of 300G+900G hard disk in production
Basic partition (MBR | GPT)-> Filesystem-> mount
Logical volume LVM-> Filesystem-> mount
VG is called volume group
Extents is called extension block
PE: Physical extent physical extension 4m 8m 16m 32m 64m specify-s 8m when creating VG
LE: Logical extent logical extension
In the actual work of Sina
Starting the Linux operating system in VMware environment and adding a new partition requires the identity of a root account.
3.1 [fdisk-l] the maximum partition is / dev/sda3, indicating that the newly created partition will be sda4
3.2 enter [fdisk / dev/sda]
3.2.1 enter [m] at the command line prompt
3.2.2 enter the command [n] to add a new partition.
3.2.3 enter the command [p] to create the primary partition.
3.2.4 enter [enter] and select the default size, so that no space is wasted
3.2.5 enter "enter" and select the default start cylinder.
3.2.6 enter [w] to keep the modification
Enter [reboot] to restart linux, which must be reboot, otherwise / dev/sda4 cannot be formatted.
3.4 only in the / dev/ directory can you see the new partition such as / dev/sda4
3.5 [mkfs.ext2 / dev/sda4] formatting
3.6 create a disk4 directory under the root directory
3.7 [mount / dev/sda4 / disk4/] mount the partition to / disk4/
3.8 modify the / etc/fstab file in vim, add a line [/ dev/sda4 / disk4 ext2 defaults 00], and save it to realize automatic boot mount.
Note that a virtual machine with a snapshot needs to add a hard disk after installing software
First, create a LVM
0. Prepare the physical disk
It could be: / dev/sdb / dev/sdc1
[root@server0 ~] # ll / dev/vd {cmeno dpene}
Brw-rw----. 1 root disk 253, 32 Jun 6 17:38 / dev/vdc
Brw-rw----. 1 root disk 253, 48 Jun 6 17:38 / dev/vdd
Brw-rw----. 1 root disk 253, 64 Jun 6 17:38 / dev/vde
1. Pv
[root@server0 ~] # pvcreate / dev/vdd
Physical volume "/ dev/vdd" successfully created
[root@server0 ~] # pvscan
PV / dev/vdd lvm2 [2.00 GiB]
Total: 1 [2.00 GiB] / in use: 0 [0] / in no VG: 1 [2.00 GiB]
[root@server0 ~] # pvs
PV VG Fmt Attr PSize PFree
/ dev/vdd lvm2 a muri-2.00g 2.00g
2. Vg
[root@server0 ~] # vgcreate vg1 / dev/vdd
Volume group "vg1" successfully created
[root@server0 ~] # vgs
VG # PV # LV # SN Attr VSize VFree
Vg1 1 00 wz--n- 2.00g 2.00g
[root@server0 ~] # vgscan
Reading all physical volumes. This may take a while...
Found volume group "vg1" using metadata type lvm2
[root@server0 ~] # vgdisplay vgdisplay datevg
-Volume group
VG Name vg1
System ID
Format lvm2
Metadata Areas 1
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 1
Act PV 1
VG Size 2.00 GiB
PE Size 4.00 MiB
Total PE 511
Alloc PE / Size 0 / 0
Free PE / Size 511 / 2.00 GiB
VG UUID 7E4tlj-l0a2-ph62-OytH-eaq7-58K6-2S4n8V
3. Lv
[root@server0] # lvcreate-l 10-n lv1 vg1
[root@server0] # lvcreate-L 200m-n lv2 vg1
[root@server0 ~] # lvscan
ACTIVE'/ dev/vg1/lv1' [640.00 MiB] inherit
ACTIVE'/ dev/vg1/lv2' [256.00 MiB] inherit
4. Create a file system and mount it
[root@server0 ~] # mkfs.xfs / dev/vg1/lv1
[root@server0 ~] # mkfs.ext4 / dev/vg1/lv2
[root@server0 ~] # mkdir / mnt/lv1 / mnt/lv2
[root@server0 ~] # vim / etc/fstab
/ dev/vg1/lv1 / mnt/lv1 xfs defaults 0 0
/ dev/vg1/lv2 / mnt/lv2 ext4 defaults 0 0
[root@server0] # mount-a
[root@server0 ~] # df
Filesystem 1K-blocks Used Available Use% Mounted on
/ dev/mapper/vg1-lv1 651948 32928 619020 6 / mnt/lv1
/ dev/mapper/vg1-lv2 245671 2062 226406 1% / mnt/lv2
II. VG management
= = expand VG vgextend==
1. Pv
[root@server0 ~] # pvcreate / dev/vde
2. Vgextend
[root@server0 ~] # vgextend vg1 / dev/vde
Volume group "vg1" successfully extended
[root@server0 ~] # vgs
VG # PV # LV # SN Attr VSize VFree
Vg1 2 2 0 wz--n- 3.99g 3.76g
= = reduce VG vgreduce==
Data migration is usually done first.
1. View the usage of PV in the current VG
[root@server0 ~] # pvs
PV VG Fmt Attr PSize PFree
/ dev/vdd vg1 lvm2 a muri-2.00g 1.76g
/ dev/vde vg1 lvm2 a muri-2.00g 2.00g
2. Pvmove data to other PV
[root@server0 ~] # pvmove / dev/vdd
/ dev/vdd: Moved: 16.7%
/ dev/vdd: Moved: 100.0%
[root@server0 ~] # pvs
PV VG Fmt Attr PSize PFree
/ dev/vdd vg1 lvm2 a muri-2.00g 2.00g
/ dev/vde vg1 lvm2 a muri-2.00g 1.76g
3.vgreduce VG
[root@server0 ~] # vgreduce vg1 / dev/vdd
Removed "/ dev/vdd" from volume group "vg1"
[root@server0 ~] # vgs
VG # PV # LV # SN Attr VSize VFree
Vg1 1 2 0 wz--n- 2.00g 1.76g
III. Expansion of LV
1. Lv expansion
[root@server0 ~] # vgs
VG # PV # LV # SN Attr VSize VFree
Vg1 2 2 0 wz--n- 1.88g 1.00g
[root@server0] # lvextend-L 800m / dev/vg1/lv1
[root@server0] # lvextend-L + 800m / dev/vg1/lv1
[root@server0 ~] # lvextend-l 15 / dev/vg1/lv1
[root@server0] # lvextend-l + 15 / dev/vg1/lv1
= =
+ 50%FREE
= =
[root@server0 ~] # lvscan
ACTIVE'/ dev/vg1/lv1' [768.00 MiB] inherit
ACTIVE'/ dev/vg1/lv2' [512.00 MiB] inherit
2. FS expansion
[root@server0 ~] # df-Th
/ dev/mapper/vg1-lv1 xfs 637M 67M 570M 11% / mnt/lv1
/ dev/mapper/vg1-lv2 ext4 240M 32m 192 M 15% / mnt/lv2
A. Xfs
[root@server0 ~] # xfs_growfs / dev/vg1/lv1
B. Ext2/3/4
[root@server0 ~] # resize2fs / dev/vg1/lv2
[root@server0 ~] # df-Th
Filesystem Type Size Used Avail Use% Mounted on
/ dev/mapper/vg1-lv1 xfs 765M 67M 698m 9% / mnt/lv1
/ dev/mapper/vg1-lv2 ext4 488M 32m 429m 7% / mnt/lv2
~
1. Create pv
[root@localhost ~] # pvcreate / dev/sda5 / dev/sda6
[root@localhost ~] # pvdisplay
[root@localhost ~] # pvs
two。 Create vg
[root@localhost ~] # vgcreate vg0 / dev/sda5 / dev/sda6
[root@localhost ~] # vgdisplay
[root@localhost ~] # vgs
3. Create lv
[root@localhost] # lvcreate-L 250m-n / dev/vg0/lv0 vg0
[root@localhost ~] # lvdisplay
[root@localhost ~] # lvs
Note:
Pv cannot cross vg
Lv cannot cross vg
Multiple vg can be created in the system
Multiple lv can be created in vg
Delete lvm
1.umount / dev/vg0/lv0
2. [root@localhost ~] # lvremove / dev/vg0/lv0
3. [root@localhost ~] # vgremove vg0
4. [root@localhost] # pvremove / dev/sda {5pm 6je 8}
What do the applications in the enterprise do if the root partition is full?
Df-h view
Pvcreate / dev/sdb
Vgs
Vgextend centos / dev/sdb
Lvscan
Lvextend-L + 5G / dev/centos/root
Df-T
Xfs_growfs / dev/centos/root
Df-Th
Lvextend-L + 5G / dev/centos/root
Xfs_growfs / dev/centos/root
Df-h
Prepare 3 hard drives but not partition-PV----VG---LV
Lsblk
# # creating PV
Pvcreate / dev/sdb
# # View the current PV
Pvscan
Pvs
Vgcreate datavg / dev/sdb (datavg is the name)
Vgscan
Pvscan # # get echo pv/dev/sdb added to VG datevg capacity XXfree
# create LV
Lvcreate-L 200m-n lv1 datavg-L (specify the size of the lv) specified as 200m lv1 from the name created from datevg
Lvcreate-L 300m-n lv2 datavg
Lvscan # # get echo / dev/datevg/lv1 200m
/ dev/datevg/lv2 300m
At this time, look at lsblk to see / dev/sdb????.
# # format and create file system mount
Mkfs.xfs / dev/datevg/lv1
Mkfs.ext4 / dev/datevg/lv2
Mkdir / mnt/lv1 / mnt/lv2
Mounting
Mount / dev/datevg/lv1 / mnt/lv1
Mount / dev/datevg/lv2 / mnt/lv2
Mount-a
Df- h (df-Th) plus TYPE type
LVM completed
# # #
Expand VG
Vgs
Pvcreate / dev/sdc becomes PV first
Vgextend datevg / dev/sdc View pvscan
The vgs free enlargement experiment is successful.
Continue to expand capacity
Pvcreate / dev/sdd
Vgextend datevg / dev/sdd
Keep looking at VFree and keep getting bigger.
# # #
Reduce VG data migration!
Pvs View
Pvmove / dev/sdb / dev/sdc throws sdb data to sdc
Vgreduce datevg / dev/sdb
Pvscan
View the changes. Data migration completed
Note:
Pv cannot cross vg
Lv cannot cross vg
Multiple vg can be created in the system
Multiple lv can be created in vg
