10-14-2020

LVM – Logcial Volume Manager

11-15-2020

https://youtu.be/3oC5SgcoBf0

/dev/sdc

8GB

/dev/sdd

16GB

/dev/sde

24GB

Logical Volume Group – zmpt1

48GB

Accounting

4GB

Finance

6GB

2GB

+6G

Recruiting

4 GB

Free space 26GB

LVM stand for Logical Volume Management, it’s a system of managing logical voumes or file systems, that is much more advanced and flexlible than the traditional method of partitioning a disk into one or more segments and formatting that parition with filesystem.

File system – ext4 or xfs

[root@zmpt01 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

sda 8:0 0 16G 0 disk

├─sda1 8:1 0 1G 0 part /boot

└─sda2 8:2 0 15G 0 part

├─centos-root 253:0 0 13.4G 0 lvm /

└─centos-swap 253:1 0 1.6G 0 lvm [SWAP]

sdb 8:16 0 16G 0 disk

├─sdb1 8:17 0 8G 0 part

├─sdb2 8:18 0 4G 0 part

└─sdb3 8:19 0 2G 0 part

sdc 8:32 0 8G 0 disk

sdd 8:48 0 16G 0 disk

sde 8:64 0 24G 0 disk

[root@zmpt01 ~]# pvcreate /dev/sdc /dev/sdd /dev/sde

Physical volume "/dev/sdc" successfully created.

Physical volume "/dev/sdd" successfully created.

Physical volume "/dev/sde" successfully created.

Command	Disk1	Disk 2	Disk 3
Pvcreate	/dev/sdc	/dev/sdd	/dev/sde

[root@zmpt01 ~]# blkid

/dev/sdc: UUID="pYcEYd-WWPb-cwhu-7dn5-lMIk-vWhk-7B9x6x" TYPE="LVM2_member"

/dev/sdd: UUID="MnAGcr-jORK-JhHN-1vBB-xFtf-ECl6-uWYRS3" TYPE="LVM2_member"

/dev/sde: UUID="FpAXdB-xeBK-Hdrq-HKZa-rmF0-l0PF-sK1sGt" TYPE="LVM2_member"

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc lvm2 --- 8.00g 8.00g

/dev/sdd lvm2 --- 16.00g 16.00g

/dev/sde lvm2 --- 24.00g 24.00g

[root@zmpt01 ~]# vgcreate zmpt1 /dev/sdc /dev/sdd /dev/sde

Volume group "zmpt1" successfully created

zmpt1 now acts as a single disk

Command	Volume group name	Disk 1	Disk 2	Diesk 3
vgcreate	zmpt1	/dev/sdc	/dev/sdd	/dev/sde

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 3 0 0 wz--n- <47.99g <47.99g

[root@zmpt01 ~]# vgdisplay zmpt1

--- Volume group ---

VG Name zmpt1

System ID

Format lvm2

Metadata Areas 3

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 3

Act PV 3

VG Size <47.99 GiB

PE Size 4.00 MiB

Total PE 12285

Alloc PE / Size 0 / 0

Free PE / Size 12285 / <47.99 GiB

VG UUID pC41AQ-xwrj-NlkE-3B1i-eXcL-tTEF-NedVpe

Accounting	4GB
Finance	6GB
HR	2GB
Recruiting	4GB

[root@zmpt01 ~]# lvcreate -n Accounting -L 4G zmpt1

Logical volume "Accounting" created.

command	New	Logical volume name	Logical	Size	Volume Group
Lvcreate	-n	Accounting	-L	4G	Zmpt1

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 3 1 0 wz--n- <47.99g <43.99g

[root@zmpt01 ~]# lvdisplay zmpt1

--- Logical volume ---

LV Path /dev/zmpt1/Accounting

LV Name Accounting

VG Name zmpt1

LV UUID EnuV1G-5Suf-PfYM-KMAH-XY3O-as1A-K2rT0W

LV Write Access read/write

LV Creation host, time zmpt01.prod.zmprotech.com, 2020-11-15 16:23:14 -0500

LV Status available

# open 0

LV Size 4.00 GiB

Current LE 1024

Segments 1

Allocation inherit

Read ahead sectors auto

- currently set to 8192

Block device 253:2

[root@zmpt01 ~]# lvs zmpt1

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

Accounting zmpt1 -wi-a----- 4.00g

Mount the LVM paritition

[root@zmpt01 ~]# mkdir /accounting

[root@zmpt01 ~]# mount /dev/zmpt1/Accounting /accounting

[root@zmpt01 ~]# df –h

/dev/mapper/zmpt1-Accounting 4.0G 33M 4.0G 1% /accounting

[root@zmpt01 ~]# lvcreate -n Finance -L 6G zmpt1

Logical volume "Finance" created.

[root@zmpt01 ~]# lvcreate -n HR -L 2G zmpt1

Logical volume "HR" created.

[root@zmpt01 ~]# lvcreate -n Recruiting -L 4G zmpt1

Logical volume "Recruiting" created.

[root@zmpt01 ~]# mkdir /finance

[root@zmpt01 ~]# mkdir /hr

[root@zmpt01 ~]# mkdir /recruiting

[root@zmpt01 ~]# mkfs.xfs /dev/zmpt1/Finance

[root@zmpt01 ~]# mkfs.xfs /dev/zmpt1/HR

[root@zmpt01 ~]# mkfs.xfs /dev/zmpt1/Recruiting

[root@zmpt01 ~]# mount /dev/zmpt1/Finance /finance/

[root@zmpt01 ~]# mount /dev/zmpt1/HR /hr/

[root@zmpt01 ~]# mount /dev/zmpt1/Recruiting /recruiting/

[root@zmpt01 ~]# df –h

/dev/mapper/zmpt1-Accounting 4.0G 33M 4.0G 1% /accounting

/dev/mapper/zmpt1-Finance 6.0G 33M 6.0G 1% /finance

/dev/mapper/zmpt1-HR 2.0G 33M 2.0G 2% /hr

/dev/mapper/zmpt1-Recruiting 4.0G 33M 4.0G 1% /recruiting

The partitions are created randomly

[root@zmpt01 ~]# lsblk

sdc 8:32 0 8G 0 disk

├─zmpt1-Accounting 253:2 0 4G 0 lvm /accounting

└─zmpt1-HR 253:4 0 2G 0 lvm /hr

sdd 8:48 0 16G 0 disk

├─zmpt1-Finance 253:3 0 6G 0 lvm /finance

└─zmpt1-Recruiting 253:5 0 4G 0 lvm /recruiting

sde 8:64 0 24G 0 disk

[root@zmpt01 ~]# vi /etc/fstab

/dev/mapper/zmpt1-Accounting /accounting xfs defaults 0 0

/dev/mapper/zmpt1-Finance /finance xfs defaults 0 0

/dev/mapper/zmpt1-HR /hr xfs defaults 0 0

/dev/mapper/zmpt1-Recruiting /recruiting xfs defaults 0 0

[root@zmpt01 ~]# mount -a

[root@zmpt01 ~]# init 6

[root@zmpt01 ~]# df -h

Filesystem Size Used Avail Use% Mounted on

devtmpfs 484M 0 484M 0% /dev

tmpfs 496M 0 496M 0% /dev/shm

tmpfs 496M 6.8M 489M 2% /run

tmpfs 496M 0 496M 0% /sys/fs/cgroup

/dev/mapper/centos-root 14G 1.8G 12G 14% /

/dev/mapper/zmpt1-Accounting 4.0G 33M 4.0G 1% /accounting

/dev/mapper/zmpt1-HR 2.0G 33M 2.0G 2% /hr

/dev/mapper/zmpt1-Recruiting 4.0G 33M 4.0G 1% /recruiting

/dev/mapper/zmpt1-Finance 6.0G 33M 6.0G 1% /finance

/dev/sda1 1014M 136M 879M 14% /boot

tmpfs 100M 0 100M 0% /run/user/0

Extedning the Logical Volume

Simulate the disk is full HR

[root@zmpt01 hr]# dd if=/dev/zero of=zafar1 bs=4096 count=+2G

/dev/mapper/zmpt1-HR 2.0G 2.0G 20K 100% /hr

Determine the free space available

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 3 4 0 wz--n- <47.99g <31.99g < ----available disk space

[root@zmpt01 ~]# vgdisplay zmpt1

Alloc PE / Size 4096 / 16.00 GiB

Free PE / Size 8189 / <31.99 GiB < ---available disk space

[root@zmpt01 ~]# lvextend -L +6G /dev/mapper/zmpt1-HR

Size of logical volume zmpt1/HR changed from 2.00 GiB (512 extents) to 8.00 GiB (2048 extents).

Logical volume zmpt1/HR successfully resized.

Command	Logical	Size	Logical Volume
lvextend	-L	+6G	/dev/mapper/zmpt1-HR

[root@zmpt01 ~]# xfs_growfs /dev/mapper/zmpt1-HR

[root@zmpt01 ~]# df –h

/dev/mapper/zmpt1-HR 8.0G 2.0G 6.0G 25% /hr < ---now you can see the new size

[root@zmpt01 ~]# lvcreate -n LVSWAP -L 4G zmpt1

Logical volume "LVSWAP" created.

[root@zmpt01 ~]# mkswap /dev/zmpt1/LVSWAP

Setting up swapspace version 1, size = 4194300 KiB

no label, UUID=e0908f33-9f5f-461f-9ed1-f702ff06160d

[root@zmpt01 ~]# free -h

total used free shared buff/cache available

Mem: 991M 137M 75M 6.8M 777M 702M

Swap: 1.6G 0B 1.6G

[root@zmpt01 ~]# swapon /dev/mapper/zmpt1-LVSWAP

[root@zmpt01 ~]# free -h

total used free shared buff/cache available

Mem: 991M 141M 72M 6.8M 777M 699M

Swap: 5.6G 0B 5.6G

Make entry into /etc/fstab

Adding Physical Disk

Add 40GB disk

11-22-2020

https://youtu.be/bs0FE_VAUvs

[root@zmpt01 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

sda 8:0 0 16G 0 disk

├─sda1 8:1 0 1G 0 part /boot

└─sda2 8:2 0 15G 0 part

├─centos-root 253:0 0 13.4G 0 lvm /

└─centos-swap 253:1 0 1.6G 0 lvm [SWAP]

sdb 8:16 0 16G 0 disk

├─sdb1 8:17 0 8G 0 part

├─sdb2 8:18 0 4G 0 part

└─sdb3 8:19 0 2G 0 part

sdc 8:32 0 8G 0 disk

├─zmpt1-Accounting 253:2 0 4G 0 lvm /accounting

└─zmpt1-HR 253:4 0 8G 0 lvm /hr

sdd 8:48 0 16G 0 disk

├─zmpt1-Finance 253:3 0 6G 0 lvm /finance

├─zmpt1-HR 253:4 0 8G 0 lvm /hr

└─zmpt1-Recruiting 253:5 0 4G 0 lvm /recruiting

sde 8:64 0 24G 0 disk

└─zmpt1-LVSWAP 253:6 0 4G 0 lvm

sdf 8:80 0 40G 0 disk < ---New Disk Added

sr0 11:0 1 1024M 0 rom

/dev/sdf is not part of any group yet

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 3 5 0 wz--n- <47.99g <21.99g

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0

/dev/sdd zmpt1 lvm2 a-- <16.00g 1.99g

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

Make /dev/sdf LVM formattable

[root@zmpt01 ~]# pvcreate /dev/sdf

Physical volume "/dev/sdf" successfully created.

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0

/dev/sdd zmpt1 lvm2 a-- <16.00g 1.99g

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

/dev/sdf lvm2 --- 40.00g 40.00g < ---formatted as LVM, but not part of vg – Volume Group

Add /dev/sdf to the VG – zmpt1

[root@zmpt01 ~]# vgextend zmpt1 /dev/sdf

Volume group "zmpt1" successfully extended

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0

/dev/sdd zmpt1 lvm2 a-- <16.00g 1.99g

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

/dev/sdf zmpt1 lvm2 a-- <40.00g <40.00g < ----/dev/sdf is part of zmpt1

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 4 5 0 wz--n- 87.98g 61.98g

/dev/sdd is corrupted – it need to be removed

[root@zmpt01 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

sda 8:0 0 16G 0 disk

├─sda1 8:1 0 1G 0 part /boot

└─sda2 8:2 0 15G 0 part

├─centos-root 253:0 0 13.4G 0 lvm /

└─centos-swap 253:1 0 1.6G 0 lvm [SWAP]

sdb 8:16 0 16G 0 disk

├─sdb1 8:17 0 8G 0 part

├─sdb2 8:18 0 4G 0 part

└─sdb3 8:19 0 2G 0 part

sdc 8:32 0 8G 0 disk

├─zmpt1-Accounting 253:2 0 4G 0 lvm /accounting

└─zmpt1-HR 253:4 0 8G 0 lvm /hr

sdd 8:48 0 16G 0 disk

├─zmpt1-Finance 253:3 0 6G 0 lvm /finance

├─zmpt1-HR 253:4 0 8G 0 lvm /hr

└─zmpt1-Recruiting 253:5 0 4G 0 lvm /recruiting

sde 8:64 0 24G 0 disk

└─zmpt1-LVSWAP 253:6 0 4G 0 lvm

sdf 8:80 0 40G 0 disk

sr0 11:0 1 1024M 0 rom

This command will move LVM structure, Data and Block information from /dev/sdd to /dev/sdf – link cloning

[root@zmpt01 ~]# pvmove /dev/sdd /dev/sdf

/dev/sdd: Moved: 0.14%

/dev/sdd: Moved: 42.85%

/dev/sdd: Moved: 71.44%

/dev/sdd: Moved: 100.00%

[root@zmpt01 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

sda 8:0 0 16G 0 disk

├─sda1 8:1 0 1G 0 part /boot

└─sda2 8:2 0 15G 0 part

├─centos-root 253:0 0 13.4G 0 lvm /

└─centos-swap 253:1 0 1.6G 0 lvm [SWAP]

sdb 8:16 0 16G 0 disk

├─sdb1 8:17 0 8G 0 part

├─sdb2 8:18 0 4G 0 part

└─sdb3 8:19 0 2G 0 part

sdc 8:32 0 8G 0 disk

├─zmpt1-Accounting 253:2 0 4G 0 lvm /accounting

└─zmpt1-HR 253:4 0 8G 0 lvm /hr

sdd 8:48 0 16G 0 disk

sde 8:64 0 24G 0 disk

└─zmpt1-LVSWAP 253:6 0 4G 0 lvm

sdf 8:80 0 40G 0 disk

├─zmpt1-Finance 253:3 0 6G 0 lvm /finance

├─zmpt1-HR 253:4 0 8G 0 lvm /hr

└─zmpt1-Recruiting 253:5 0 4G 0 lvm /recruiting

sr0 11:0 1 1024M 0 rom

[root@zmpt01 ~]# lvs

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

root centos -wi-ao---- 13.39g

swap centos -wi-ao---- 1.60g

Accounting zmpt1 -wi-ao---- 4.00g

Finance zmpt1 -wi-ao---- 6.00g

HR zmpt1 -wi-ao---- 8.00g

LVSWAP zmpt1 -wi-a----- 4.00g

Recruiting zmpt1 -wi-ao---- 4.00g

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0 < --- Remove the corrupted disk

/dev/sdd zmpt1 lvm2 a-- <16.00g <16.00g

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

/dev/sdf zmpt1 lvm2 a-- <40.00g 25.99g

[root@zmpt01 ~]# vgreduce zmpt1 /dev/sdd

Removed "/dev/sdd" from volume group "zmpt1"

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0

/dev/sdd lvm2 --- 16.00g 16.00g < --- Remove completed

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

/dev/sdf zmpt1 lvm2 a-- <40.00g 25.99g

/dev/sdc 8GB			/dev/sde 24GB			/dev/sdf 40GB
Logical Volume Group – zmpt1 72GB
Accounting 4GB	Finance 6GB	HR 2GB		HR +6G	Recruiting 4 GB		SWAP 4GB	Free space 46GB

Increase inodes to xfs files system /dev/sdd1

[root@zmpt01 ~]# df -i /dev/sdc

Filesystem Inodes IUsed IFree IUse% Mounted on

devtmpfs 123861 446 123415 1% /dev

[root@zmpt01 mnt]# df -i /dev/sdd1

Filesystem Inodes IUsed IFree IUse% Mounted on

/dev/sdd1 1048576 10003 1038573 1% /mnt

[root@zmpt01 ~]# xfs_growfs -m 40 /dev/sdd1

[root@zmpt01 ~]# xfs_db -f -c "sb 0" -c "p" /dev/sdd1 | grep imax_pct

imax_pct = 40

[root@zmpt01 ~]# df -i /dev/sdd1

Filesystem Inodes IUsed IFree IUse% Mounted on

/dev/sdd1 1677720 10003 1667717 1% /mnt

There is no data loss

Delete LV and VG – decommisioning of Physcial Harware

[root@zmpt01 ~]# vgs

VG #PV #LV #SN Attr VSize VFree

centos 1 2 0 wz--n- <15.00g 0

zmpt1 3 5 0 wz--n- <71.99g <45.99g < ---Target LVM to delete

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc zmpt1 lvm2 a-- <8.00g 0

/dev/sde zmpt1 lvm2 a-- <24.00g <20.00g

/dev/sdf zmpt1 lvm2 a-- <40.00g 25.99g

[root@zmpt01 ~]# umount –a

[root@zmpt01 ~]# vgremove zmpt1 -y

Logical volume "Accounting" successfully removed

Logical volume "Finance" successfully removed

Logical volume "HR" successfully removed

Logical volume "Recruiting" successfully removed

Logical volume "LVSWAP" successfully removed

Volume group "zmpt1" successfully removed

[root@zmpt01 ~]# blkid

/dev/sda1: UUID="160e6caa-b0a9-468b-9de1-04189acc84ce" TYPE="xfs"

/dev/sda2: UUID="oLnQZF-bJU0-02T3-t0wF-DhnB-2JI6-CQI9f2" TYPE="LVM2_member"

/dev/sdb1: UUID="47d30ab1-92ee-4dc8-8c79-ef9dd898e1f0" TYPE="ext4"

/dev/sdb2: UUID="e5a18729-daf6-4c7b-89db-3a5979d3c254" TYPE="xfs"

/dev/sdb3: UUID="7d459795-930e-4cc5-b737-a84b452ff04a" TYPE="swap"

/dev/sdc: UUID="pYcEYd-WWPb-cwhu-7dn5-lMIk-vWhk-7B9x6x" TYPE="LVM2_member"

/dev/sde: UUID="FpAXdB-xeBK-Hdrq-HKZa-rmF0-l0PF-sK1sGt" TYPE="LVM2_member"

/dev/sdf: UUID="ZoCio8-qWEh-NG7u-HlLR-hLph-Rpl5-d9x6mr" TYPE="LVM2_member"

/dev/mapper/centos-root: UUID="5c79b16a-cfd4-4d5a-8e9c-b9b1a37b4936" TYPE="xfs"

/dev/mapper/centos-swap: UUID="c7801c38-9828-49b2-8a12-7610376d8b8a" TYPE="swap"

/dev/sdd1: UUID="5588ebda-0031-4b2b-b80e-a5a1a68e0bf7" TYPE="xfs"

[root@zmpt01 ~]# pvs

PV VG Fmt Attr PSize PFree

/dev/sda2 centos lvm2 a-- <15.00g 0

/dev/sdc lvm2 --- 8.00g 8.00g

/dev/sde lvm2 --- 24.00g 24.00g

/dev/sdf lvm2 --- 40.00g 40.00g

[root@zmpt01 ~]# pvremove /dev/sdc /dev/sde /dev/sdf

Labels on physical volume "/dev/sdc" successfully wiped.

Labels on physical volume "/dev/sde" successfully wiped.

Labels on physical volume "/dev/sdf" successfully wiped.