Logical Volume Management (LVM) Date: 18/05/2024 Status: Tested Logical Volume Management ,  or LVM, provides a method of allocating and managing space on  mass-storage devices that is more advanced and flexible than the  traditional method of partitioning storage volumes. To find out how to set up LVM in Ubuntu,  refer to this guide , which will also show you how to resize and move partitions, and how to create snapshots. Key concepts There are 3 concepts that LVM manages: Physical volumes ( PV ) : correspond to disks. They represent the lowest abstraction level of LVM, and are used to create a volume group. Volume groups ( VG ) : are collections of physical volumes. They are pools of disk space that logical volumes can be allocated from. Logical volumes ( LV ) : correspond to partitions – they usually hold a filesystem. Unlike partitions though, they can span multiple disks (because of the way volume groups are organised) and do not have to be physically contiguous. lets open our home lab and try how LVM works. Requirements: Linux machine running baremetal or VM. 3 Disk (OS,PV1,PV2) Simulating: Create PV Create VG Creating LV Create file system Mounting Reduce LV Remove from VG Remove from OS Ubuntu with 3 disk, disk #1 Operating System, disk #2 & #3 alocated for Volume Group ubuntu@ubuntu:~$ sudo fdisk -l Disk /dev/sda: 8 GiB, 8589934592 bytes, 16777216 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 534EB29B-2FE8-482C-BB79-8C98AE4D1174 Device Start End Sectors Size Type /dev/sda1 2048 4095 2048 1M BIOS boot /dev/sda2 4096 16775167 16771072 8G Linux filesystem Disk /dev/sdb: 10 GiB, 10737418240 bytes, 20971520 sectors Disk model: VBOX HARDDISK 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/sdc: 15 GiB, 16106127360 bytes, 31457280 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes ubuntu@ubuntu:~$ Disk Capacity /dev/sda 8G /dev/sdb 10G /dev/sdc 15G   Creating PV Creating (PV) Physical Volume for  /dev/sdb   and  /dev/sdc ubuntu@ubuntu:~$ sudo lvm lvm> pvcreate /dev/sdb Physical volume "/dev/sdb" successfully created. lvm> pvcreate /dev/sdc Physical volume "/dev/sdc" successfully created. lvm> pvdisplay "/dev/sdb" is a new physical volume of "10.00 GiB" --- NEW Physical volume --- PV Name /dev/sdb VG Name PV Size 10.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID qaRqDq-0MmA-OAAC-4QnH-vvXF-12Fc-EdRep3 "/dev/sdc" is a new physical volume of "15.00 GiB" --- NEW Physical volume --- PV Name /dev/sdc VG Name PV Size 15.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID BgjRNz-7cjU-CpFe-6nNn-OxaV-OZUa-3dLsDh lvm> Creating VG Creating Volume Group (VG) and attaching  /dev/sdb   into Volume Group lvm> vgcreate ubuntu-vg /dev/sdb Volume group "ubuntu-vg" successfully created lvm> vgs VG #PV #LV #SN Attr VSize VFree ubuntu-vg 1 0 0 wz--n- <10.00g <10.00g lvm> vgdisplay --- Volume group --- VG Name ubuntu-vg 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 <10.00 GiB PE Size 4.00 MiB Total PE 2559 Alloc PE / Size 0 / 0 Free PE / Size 2559 / <10.00 GiB VG UUID E2OrNE-p76Y-UwIl-NiQs-ozHJ-C8ZT-xc1Mqy lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g <10.00g /dev/sdc lvm2 --- 15.00g 15.00g lvm>   Creating LV Create Logical Volume (LV) and use all (100%) of free space on  ubuntu-vg  . lvm> lvcreate -l 100%free -n ubuntu-lv ubuntu-vg Logical volume "ubuntu-lv" created. lvm> lvm> lvdisplay --- Logical volume --- LV Path /dev/ubuntu-vg/ubuntu-lv LV Name ubuntu-lv VG Name ubuntu-vg LV UUID d4pPYZ-HwAx-w4wK-NzNr-xd2P-FXPp-fmLaYr LV Write Access read/write LV Creation host, time ubuntu, 2024-05-19 09:54:44 +0000 LV Status available # open 0 LV Size <10.00 GiB Current LE 2559 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 lvm> Creating file system Create file system and ready to mount. ubuntu@ubuntu:~$ sudo mkfs -t ext4 /dev/ubuntu-vg/ubuntu-lv mke2fs 1.46.5 (30-Dec-2021) Creating filesystem with 2620416 4k blocks and 655360 inodes Filesystem UUID: 3f80be60-f70e-4fd0-ac0d-4f5995be2c11 Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632 Allocating group tables: done Writing inode tables: done Creating journal (16384 blocks): done Writing superblocks and filesystem accounting information: done ubuntu@ubuntu:~$   Mounting Preparing for mounting by create folder  /data  , change owner folder and mounting the LV. sudo mkdir /data sudo chown ubuntu:ubuntu /data sudo mount /dev/ubuntu-vg/ubuntu-lv /data continue by updating  fstab  for automatic mounting every boot #sudo nano /etc/fstab #add this line /dev/ubuntu-vg/ubuntu-lv /data ext4 defaults test  fstab  before reboot using  sudo mount -a  when no error you are good to go. ubuntu@ubuntu:~$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 764K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 9.8G 24K 9.3G 1% /data ubuntu@ubuntu:~$ now we try to filling disk with data. as you can see the  /data  usage is  1%   of 9.8G total. Bellow  /data  usage  100%   (9.3G of 9.8G) after filling with data/file. ubuntu@ubuntu:/$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 756K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 9.8G 9.3G 0 100% /data ubuntu@ubuntu:/$ Volume are full and no longer able to add another data/files, we need to add more space by attaching new Physical Volume (PV) into our ubuntu-vg (VG) for expand capacity. ubuntu@ubuntu:~$ sudo lvm lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g 0 /dev/sdc lvm2 --- 15.00g 15.00g lvm> pvdisplay --- Physical volume --- PV Name /dev/sdb VG Name ubuntu-vg PV Size 10.00 GiB / not usable 4.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 2559 Free PE 0 Allocated PE 2559 PV UUID qaRqDq-0MmA-OAAC-4QnH-vvXF-12Fc-EdRep3 "/dev/sdc" is a new physical volume of "15.00 GiB" --- NEW Physical volume --- PV Name /dev/sdc VG Name PV Size 15.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID BgjRNz-7cjU-CpFe-6nNn-OxaV-OZUa-3dLsDh lvm> by using pvdisplay command we can see that /dev/sdc is not part of group VG ubuntu-vg . Now we add PV into VG  ubuntu-vg  by execute command  vgextend ubuntu-vg /dev/sdc  . this time, we only use 8G disk space of 15G total from disk capacity lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g 0 /dev/sdc lvm2 --- 15.00g 15.00g lvm> lvm> vgextend ubuntu-vg /dev/sdc Volume group "ubuntu-vg" successfully extended lvm> lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g 0 /dev/sdc ubuntu-vg lvm2 a-- <15.00g <15.00g lvm> lvm> lvextend -L +8G ubuntu-vg/ubuntu-lv Size of logical volume ubuntu-vg/ubuntu-lv changed from <10.00 GiB (2559 extents) to <18.00 GiB (4607 extents). Logical volume ubuntu-vg/ubuntu-lv successfully resized. lvm> lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g 0 /dev/sdc ubuntu-vg lvm2 a-- <15.00g <7.00g lvm> after lvextend command successfully our LV has been expanding to 18G, 10G (/dev/sdb) + 8G (dev/sdc) lvm> lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ubuntu-lv ubuntu-vg -wi-ao---- <18.00g lvm> lvdisplay --- Logical volume --- LV Path /dev/ubuntu-vg/ubuntu-lv LV Name ubuntu-lv VG Name ubuntu-vg LV UUID d4pPYZ-HwAx-w4wK-NzNr-xd2P-FXPp-fmLaYr LV Write Access read/write LV Creation host, time ubuntu, 2024-05-19 09:54:44 +0000 LV Status available # open 1 LV Size <18.00 GiB Current LE 4607 Segments 2 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 but remember, the 18G of LV is just capacity that we allocated, doesn't mean useable until we do resize filesystem by execute command  resize2fs  . ubuntu@ubuntu:~$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 756K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 9.8G 9.3G 0 100% /data ubuntu@ubuntu:~$ ubuntu@ubuntu:~$ sudo resize2fs /dev/ubuntu-vg/ubuntu-lv resize2fs 1.46.5 (30-Dec-2021) Filesystem at /dev/ubuntu-vg/ubuntu-lv is mounted on /data; on-line resizing required old_desc_blocks = 2, new_desc_blocks = 3 The filesystem on /dev/ubuntu-vg/ubuntu-lv is now 4717568 (4k) blocks long. ubuntu@ubuntu:~$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 756K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 18G 9.3G 7.6G 56% /data ubuntu@ubuntu:~$ sekarang VG  ubuntu-vg/ubuntu-lv  telah berubah menjadi 18G, untuk membuktikannya mari kita lakukan pengisian data/file kembali. ubuntu@ubuntu:~$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 756K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 18G 14G 2.8G 84% /data ubuntu@ubuntu:~$ saat ini kita akan simulasikan kebutuuhan menyimpan data sudahlah tidak besar dan kita akan me-reduce (shrink) Volume dan mengeluarkan /dev/sdc dari VG ubuntu@ubuntu:/data$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 764K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock /dev/mapper/ubuntu--vg-ubuntu--lv 18G 2.0G 15G 12% /data tmpfs 391M 4.0K 391M 1% /run/user/1000 ubuntu@ubuntu:/data$ terlihat folder  /data  masih memiki data/file namun isinya sudah tidak sebanyak sebelumnya  yg mencapai 14G. sebelum proses dilakukan sangat di sarankan untuk membackup dahulu, sebagai pencegahan jika terjadi keadaan yg tidak dinginkan, dan lakukan simulasi di evironmen lain dahulu sebagai gambaran tantangan yg akan di hadapi pada proses didepan. STOP........!!! LAKUKAN BACKUP DAN SIMULASI dahulu sangat disarankan ! jika sudah yakin mari kita mulai ubuntu@ubuntu:/$ sudo umount /data ubuntu@ubuntu:/$ sudo e2fsck -f /dev/ubuntu-vg/ubuntu-lv e2fsck 1.46.5 (30-Dec-2021) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/ubuntu-vg/ubuntu-lv: 12/1179648 files (0.0% non-contiguous), 622552/4717568 blocks ubuntu@ubuntu:/$ ubuntu@ubuntu:/$ sudo lvreduce --resizefs -L 5G /dev/ubuntu-vg/ubuntu-lv fsck from util-linux 2.37.2 /dev/mapper/ubuntu--vg-ubuntu--lv: clean, 12/1179648 files, 622552/4717568 blocks resize2fs 1.46.5 (30-Dec-2021) Resizing the filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv to 1310720 (4k) blocks. The filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv is now 1310720 (4k) blocks long. Size of logical volume ubuntu-vg/ubuntu-lv changed from <18.00 GiB (4607 extents) to 5.00 GiB (1280 extents). Logical volume ubuntu-vg/ubuntu-lv successfully resized. ubuntu@ubuntu:/$ Note: The LVM environment offers three commands to resize:  lvresize ,  lvreduce , and  lvextend . The resize let you change the size (bigger or smaller), the reduce only allows smaller sizes (i.e. at most X Gb) and the extend only allows larger sizes (i.e. at least X Gb). ubuntu@ubuntu:/$ sudo mount /data ubuntu@ubuntu:/$ ls bin data etc lib lib64 lost+found mnt proc run snap sys usr boot dev home lib32 libx32 media opt root sbin srv tmp var ubuntu@ubuntu:/$ cd /data/ ubuntu@ubuntu:/data$ df -h Filesystem Size Used Avail Use% Mounted on tmpfs 392M 764K 391M 1% /run /dev/sda2 7.8G 2.6G 4.8G 36% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 391M 4.0K 391M 1% /run/user/1000 /dev/mapper/ubuntu--vg-ubuntu--lv 4.9G 2.0G 2.6G 44% /data ubuntu@ubuntu:/data$ du -h ubuntu@ubuntu:/data$ sudo lvm lvm> lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ubuntu-lv ubuntu-vg -wi-ao---- 5.00g lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g <5.00g /dev/sdc ubuntu-vg lvm2 a-- <15.00g <15.00g lvm> pvdisplay --- Physical volume --- PV Name /dev/sdb VG Name ubuntu-vg PV Size 10.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 2559 Free PE 1279 Allocated PE 1280 PV UUID qaRqDq-0MmA-OAAC-4QnH-vvXF-12Fc-EdRep3 --- Physical volume --- PV Name /dev/sdc VG Name ubuntu-vg PV Size 15.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 3839 Free PE 3839 Allocated PE 0 PV UUID BgjRNz-7cjU-CpFe-6nNn-OxaV-OZUa-3dLsDh dapat di lihat /dev/sdc masih berada dalam VG ubuntu-vg namun tidak digunakan. lvm> pvdisplay --- Physical volume --- PV Name /dev/sdb VG Name ubuntu-vg PV Size 10.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 2559 Free PE 1279 Allocated PE 1280 PV UUID qaRqDq-0MmA-OAAC-4QnH-vvXF-12Fc-EdRep3 --- Physical volume --- PV Name /dev/sdc VG Name ubuntu-vg PV Size 15.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 3839 Free PE 3839 Allocated PE 0 PV UUID BgjRNz-7cjU-CpFe-6nNn-OxaV-OZUa-3dLsDh lvm> pvmove /dev/sdc No data to move for ubuntu-vg. lvm> vgdisplay --- Volume group --- VG Name ubuntu-vg System ID Format lvm2 Metadata Areas 2 Metadata Sequence No 5 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 1 Max PV 0 Cur PV 2 Act PV 2 VG Size 24.99 GiB PE Size 4.00 MiB Total PE 6398 Alloc PE / Size 1280 / 5.00 GiB Free PE / Size 5118 / 19.99 GiB VG UUID E2OrNE-p76Y-UwIl-NiQs-ozHJ-C8ZT-xc1Mqy lvm> vgreduce ubuntu-vg /dev/sdc Removed "/dev/sdc" from volume group "ubuntu-vg" lvm> lvm> vgdisplay --- Volume group --- VG Name ubuntu-vg System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 6 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 1 Max PV 0 Cur PV 1 Act PV 1 VG Size <10.00 GiB PE Size 4.00 MiB Total PE 2559 Alloc PE / Size 1280 / 5.00 GiB Free PE / Size 1279 / <5.00 GiB VG UUID E2OrNE-p76Y-UwIl-NiQs-ozHJ-C8ZT-xc1Mqy lvm> pvdisplay --- Physical volume --- PV Name /dev/sdb VG Name ubuntu-vg PV Size 10.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 2559 Free PE 1279 Allocated PE 1280 PV UUID qaRqDq-0MmA-OAAC-4QnH-vvXF-12Fc-EdRep3 "/dev/sdc" is a new physical volume of "15.00 GiB" --- NEW Physical volume --- PV Name /dev/sdc VG Name PV Size 15.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID BgjRNz-7cjU-CpFe-6nNn-OxaV-OZUa-3dLsDh lvm> lvdisplay --- Logical volume --- LV Path /dev/ubuntu-vg/ubuntu-lv LV Name ubuntu-lv VG Name ubuntu-vg LV UUID d4pPYZ-HwAx-w4wK-NzNr-xd2P-FXPp-fmLaYr LV Write Access read/write LV Creation host, time ubuntu, 2024-05-19 09:54:44 +0000 LV Status available # open 1 LV Size 5.00 GiB Current LE 1280 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 lvm> lvm> lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert ubuntu-lv ubuntu-vg -wi-ao---- 5.00g lvm> pvs PV VG Fmt Attr PSize PFree /dev/sdb ubuntu-vg lvm2 a-- <10.00g <5.00g /dev/sdc lvm2 --- 15.00g 15.00g lvm> vgs VG #PV #LV #SN Attr VSize VFree ubuntu-vg 1 1 0 wz--n- <10.00g <5.00g lvm> ubuntu@ubuntu:/data$ sudo fdisk -l Disk /dev/sda: 8 GiB, 8589934592 bytes, 16777216 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 534EB29B-2FE8-482C-BB79-8C98AE4D1174 Device Start End Sectors Size Type /dev/sda1 2048 4095 2048 1M BIOS boot /dev/sda2 4096 16775167 16771072 8G Linux filesystem Disk /dev/sdb: 10 GiB, 10737418240 bytes, 20971520 sectors Disk model: VBOX HARDDISK 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/sdc: 15 GiB, 16106127360 bytes, 31457280 sectors Disk model: VBOX HARDDISK 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/ubuntu--vg-ubuntu--lv: 5 GiB, 5368709120 bytes, 10485760 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 ubuntu@ubuntu:/data$ ubuntu@ubuntu:/data$ sudo fdisk -l Disk /dev/sda: 8 GiB, 8589934592 bytes, 16777216 sectors Disk model: VBOX HARDDISK Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 534EB29B-2FE8-482C-BB79-8C98AE4D1174 Device Start End Sectors Size Type /dev/sda1 2048 4095 2048 1M BIOS boot /dev/sda2 4096 16775167 16771072 8G Linux filesystem Disk /dev/sdb: 10 GiB, 10737418240 bytes, 20971520 sectors Disk model: VBOX HARDDISK 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/ubuntu--vg-ubuntu--lv: 5 GiB, 5368709120 bytes, 10485760 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 ubuntu@ubuntu:/data$ LVM memudahkan dalam peng-alokasi-an partisi/volume, mudah untuk di perbesar dan di perkecil ( expand - shrink ), kita dapat menambahkan storage menjadi satu volume sebanyak yg kita mau. walaupun begitu ada yg perlu di perhatikan. LVM bukan penganti RAID LVM tidak menambah performa kecepatan transfer. LVM berkerja sepert RAID 0 LVM tidak fault tolerance, dengan kata lain, jika salah satu disk dalam VG rusak maka kita akan kehilangan data atau mungkin malah kehilangan seluruh VG Untuk mereduce LVM diperlukan unmount, oleh sebab itu disarakan Gunakan LVM diluar path default agar bisa di unmount on the fly Gunakan LVM diatas RAID, dimana RAID sebagai Fault tolerance dapat memberikan ketangguhan system dari resiko data lost karena disk rusak/bad sector.