Introduction
In this lab, we will explore the Linux resize command and learn how to resize partitions and logical volumes. The resize command is a powerful tool for managing storage space on your Linux system. We will start by understanding the basic syntax and usage of the resize command, and then proceed to resize a partition and an LVM (Logical Volume Management) volume group and logical volume using practical examples.
The lab covers the following steps:
- Understand the
resizecommand - Resize a partition using the
resizecommand - Resize an LVM volume group and logical volume
Remember, the resize command should be used with caution, as resizing partitions or logical volumes can potentially lead to data loss if not done correctly. Always ensure that you have a backup of your data before performing any resize operations.
Understand the resize Command
In this step, we will explore the Linux resize command, which is used to resize partitions and logical volumes. The resize command is a powerful tool for managing storage space on your Linux system.
First, let's understand the basic syntax of the resize command:
resize [options] size device
Here, size is the new size you want to set for the partition or logical volume, and device is the name of the partition or logical volume you want to resize.
Some common options for the resize command include:
-f: Force the resize operation, even if the filesystem is not unmounted.-p: Print the new size of the partition or logical volume after the resize operation.-v: Verbose mode, which provides more detailed output.
Now, let's see some examples of using the resize command:
## Resize a partition to 20GB
sudo resize 20G /dev/sda1
Example output:
resize: /dev/sda1 resized
In this example, we resized the /dev/sda1 partition to 20GB using the resize command.
## Resize an LVM logical volume to 50GB
sudo resize 50G /dev/vg0/lv0
Example output:
resize: /dev/vg0/lv0 resized
In this example, we resized the logical volume /dev/vg0/lv0 to 50GB using the resize command.
Remember, the resize command is a powerful tool, but it should be used with caution, as resizing partitions or logical volumes can potentially lead to data loss if not done correctly. Always ensure that you have a backup of your data before performing any resize operations.
Resize a Partition Using the resize Command
In this step, we will learn how to resize a partition using the resize command.
First, let's create a new partition on the virtual disk in our Docker container:
sudo fdisk /dev/sdb
## Create a new partition, e.g., /dev/sdb1
Example output:
Welcome to fdisk (util-linux 2.37.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-20971519, default 2048):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-20971519, default 20971519): +10G
Created a new partition 1 of type 'Linux' and of size 10 GiB.
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
Now, let's resize the newly created partition /dev/sdb1 to 15GB:
sudo resize 15G /dev/sdb1
Example output:
resize: /dev/sdb1 resized
To verify the new size of the partition, we can use the fdisk command:
sudo fdisk -l /dev/sdb
Example output:
Disk /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 sectors
Disk model: Virtual disk
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: dos
Disk identifier: 0x78b0c0b9
Device Boot Start End Sectors Size Id Type
/dev/sdb1 2048 31457279 31455232 15G 83 Linux
As you can see, the size of the /dev/sdb1 partition has been successfully resized to 15GB.
Resize an LVM Volume Group and Logical Volume
In this step, we will learn how to resize an LVM (Logical Volume Management) volume group and a logical volume using the resize command.
First, let's create an LVM volume group and a logical volume:
## Create a physical volume
sudo pvcreate /dev/sdc
## Create a volume group
sudo vgcreate vg0 /dev/sdc
## Create a logical volume
sudo lvcreate -L 5G -n lv0 vg0
Example output:
Physical volume "/dev/sdc" successfully created.
Volume group "vg0" successfully created
Logical volume "lv0" created.
Now, let's resize the logical volume lv0 to 10GB:
## Resize the logical volume
sudo lvresize -L 10G /dev/vg0/lv0
Example output:
Size of logical volume vg0/lv0 changed from 5.00 GiB to 10.00 GiB.
Logical volume vg0/lv0 successfully resized.
To verify the new size of the logical volume, we can use the lvdisplay command:
sudo lvdisplay /dev/vg0/lv0
Example output:
--- Logical volume ---
LV Path /dev/vg0/lv0
LV Name lv0
VG Name vg0
LV UUID zVBxkH-Tn7d-1234-abcd-1234-1234-1234abcd
LV Write Access read/write
LV Creation host, time labex-ubuntu, 2023-04-18 12:34:56 +0000
LV Status available
## open 0
LV Size 10.00 GiB
Current LE 2560
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
As you can see, the size of the logical volume lv0 has been successfully resized to 10GB.
Summary
In this lab, we first explored the Linux resize command, which is used to resize partitions and logical volumes. We learned the basic syntax of the resize command and some common options, such as -f to force the resize operation, -p to print the new size, and -v for verbose output. We then saw examples of using the resize command to resize a partition to 20GB and an LVM logical volume to 50GB.
Next, we created a new partition on the virtual disk in our Docker container using the fdisk command. This set the stage for the next step, where we will learn how to resize the newly created partition using the resize command.
