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content/en/linux-lifehacks/how-to-create-lvm-logical-volume.md

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+---
+title: "Linux: How to create LVM logical volume"
+date: "2022-05-15"
+---
+### First step: creating a physical volume
+After you have attached the disk to a physical server or virtual machine, you need to type
+this command:
+```bash
+sudo fdisk -l
+```
+<!--more-->
+to make sure the drive is recognized by the operating system, and to identify the drive name. Output
+of command will be something like this:
+```plaintext
+Disk /dev/vdb: 10 GiB, 10737418240 bytes, 20971520 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
+```
+Once you have identified the drive name (in our case it is `/dev/vdb`), you can create
+physical volume using the command:
+```bash
+sudo pvcreate /dev/vdb
+```
+You will see output like this:
+```plaintext
+kostya@ubuntu-21-04:~$ sudo pvcreate /dev/vdb
+Physical volume "/dev/vdb" successfully created.
+kostya@ubuntu-21-04:~$
+```
+### Step two: create the volume group
+Now we need to create a volume group. This is done by the following command:
+```bash
+sudo vgcreate {vgname} {pvname}
+```
+In our case, the command will look like this:
+```bash
+sudo vgcreate vg-example /dev/vdb
+```
+The command output will look like this:
+```plaintext
+kostya@ubuntu-21-04:~$ sudo vgcreate vg-example/dev/vdb
+Volume group "vg-example" successfully created
+kostya@ubuntu-21-04:~$
+```
+### Step three: creating the logical volume
+Creating a logical volume can be done with the following command:
+```bash
+sudo lvcreate --size {size} --name {lv-name} {vg-name}
+```
+In our case, it will be:
+```bash
+sudo lvcreate --size 5G --name lv-example vg-example
+```
+You will see output like this:
+```plaintext
+kostya@ubuntu-21-04:~$ sudo lvcreate --size 5G --name lv-example vg-example
+Logical volume "lv-example" created.
+kostya@ubuntu-21-04:~$
+```
+If you want the logical volume to use all the free space in the volume group, then run the command:
+```bash
+sudo lvcreate --extents 100%FREE --name lv-example vg-example
+```
+### Fourth step: creating the filesystem
+To create an xfs filesystem, type the command:
+```bash
+sudo mkfs.xfs /dev/vg-example/lv-example
+```
+The command output will look like this:
+```plaintext
+kostya@ubuntu-21-04:~$ sudo mkfs.xfs/dev/vg-example/lv-example
+meta-data =/dev/vg-example/lv-example isize = 512 agcount = 4, agsize = 327680 blks
+            = sectsz = 512 attr = 2, projid32bit = 1
+            = crc = 1 finobt = 1, sparse = 1, rmapbt = 0
+            = reflink = 1 bigtime = 0
+data = bsize = 4096 blocks = 1310720, imaxpct = 25
+            = sunit = 0 swidth = 0 blks
+naming = version 2 bsize = 4096 ascii-ci = 0, ftype = 1
+log = internal log bsize = 4096 blocks = 2560, version = 2
+            = sectsz = 512 sunit = 0 blks, lazy-count = 1
+realtime = none extsz = 4096 blocks = 0, rtextents = 0
+Discarding blocks ... Done.
+kostya@ubuntu-21-04:~$
+```
+To create an ext4 filesystem, replace the `mkfs.xfs` command with `mkfs.ext4`
+### Step Five: Mount the Logical Volume
+For example, suppose you want to mount the newly created logical volume to the `/opt` folder. In this
+case, add this line to file `/etc/fstab`:
+```bash
+/dev/vg-example/lv-example /opt xfs defaults 0 1
+```
+After that, type the command:
+```bash
+sudo mount -a
+```
+You can verify that the logical volume has been mounted successfully using the command:
+```bash
+df -h /opt
+```
+The output should be like this:
+```plaintext
+kostya@ubuntu-21-04:~$ df -h /opt/
+Filesystem                         Size  Used Avail Use% Mounted on
+/dev/mapper/vg--random-lv--random  5.0G   68M  5.0G   2% /opt
+kostya@ubuntu-21-04:~$
+```