How to Move the Partition to a New Partition in the Linux Server?

If you install a Linux server, you will usually install it with only one partition and not separate the other partitions. Problems will arise if one of these partitions uses a large enough hard disk, resulting in you running out of HDD space on your Linux server.

Problem

How to move the partition to a new partition in the Linux server?

Solution

In this article, I use the Ubuntu Server OS, and this article should be applied to any Linux distribution. Currently, the condition of the hard disk on my Ubuntu server is like the image below:

Condition of the hard disk in my Ubuntu server

From the image above, the root partition only has a free HDD of 9 percent. After I checked, it turned out that the cause was the /var partition, which took up a lot of hard disk so I want to move the /var partition to the new partition.

Here are the steps to move the partition to a new partition in the Linux Server:

Info

The steps in this article will make your Linux server enter maintenance mode which means that the Linux server cannot be accessed from anywhere results in the application or database that may be in the Linux server also inaccessible. So discuss first with your boss if you want to do the steps in this article

1. Add a new hard drive

I insert a new 10 GB HDD into my Linux server. After that, I check if the new HDD is detected by Linux using the command:

fdisk -l

From the image above, it can be seen that the new HDD was detected by Linux with a partition in sdb.

2. Create a new partition

Run the command below to create a new partition in Linux (Adjust to the hard disk partition detected on your Linux server after typing the fdisk -l command):

fdisk /dev/sdb

Press the n and p keys, then the number ,1 and enter 2x, then press the w button as seen in the image below:

Then create a filesystem from the new HDD, and I want to use ext4 for the filesystem of the new HDD using the command:

mkfs.ext4 /dev/sdb1

Create a filesystem in the partition of the new HDD

3. Create and mount a new folder

After that, create a new folder using the command:

mkdir /mnt/newvar

Then, mount the new partition to the new folder using the command:

mount /dev/sdb1 /mnt/newvar

move the partition to a new partition — Create and mount a new folder

4. Enter maintenance mode

Type the command below:

init 1

to enter the rescue mode:

After that, press the Enter button to enter maintenance mode.

5. Copy the folder

Go to the /var folder and copy all the files and folders in the folder into a new folder by typing the following commands:

cd /var
cp -ax * /mnt/newvar

6. Rename the folder

Once the copy process is complete, change the /var folder to the var.old folder and then create a new /var folder using the command:

cd /
mv var var.old
mkdir /var

7. Mount the new folder

Next, do umount on the /sdb1 partition by using the command:

umount /dev/sdb1

And mount the /sdb1 partition to the new /var folder using the command:

mount /dev/sdb1 /var

8. Change the fstab file

Change the /etc/fstab file by adding the following script to the file:

/dev/sdb1	/var	ext4	defaults	0 0

9. Restart the server

After that, restart the Linux server and make sure there is no problem when the Linux server reboots.

10. Delete the folder

If the Linux server has finished restarting, then you can delete the var.old folder so that the size of the hard disk of the root partition increases by using the command:

cd /
rm -rf var.old

Note

Reboot the server again to make sure there are no problems after you delete the var.old folder. You can use the steps above when you want to move another folder to a new partition in the Linux server.

References

blog.oshim.net
phoenixnap.com