How to rename /dev/sdax(partitions) in Linux

Question

I made a partition like /part on my machine with some important data...

But I can't stand the name of it...

I want a clear solution to resolve it and change the name of it to for example /test...

As you see this is my /etc/fstab information:

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    nodev,noexec,nosuid 0       0
# / was on /dev/sda5 during installation
UUID=a21a99c4-e5b4-4197-ac5e-80d0fab1f30c /               ext4    errors=remount-ro 0       1
# /home was on /dev/sda6 during installation
UUID=2e37d833-ca34-4fa7-a5d8-a4423a5af9bc /home           ext4    defaults          0       2
# /part was on /dev/sda7 during installation
UUID=47e6e0b1-0e57-4184-a378-375b9ce315c5 /part           ext4    defaults          0       2
# swap was on /dev/sda1 during installation
UUID=485e9f78-4dce-4404-af4e-f43985525264 none            swap    sw                0       0

The point is: My information are important and I scare to manipulate it without being sure... I want a safe solution...

How is it possible?

Thank you in advance

Answer 1

• Unmount the partition:

  # umount /part
  

• Rename the directory after making sure it's not mounted:

  # mountpoint /part &>/dev/null || mv /part /best_name_ever
  

• Edit /etc/fstab to replace /part with /best_name_ever

• Remount the partition:

  mount /best_name_ever
  

The # is of course meant to represent your root prompt, not actual input to be typed in.

To test the safety of this solution or any other one on dummy data

The following instructions are (in part) stolen from Virtual Filesystem: Building A Linux Filesystem From An Ordinary File.

• Create an ordinary file with a size of 20 MB (for example):

  $ dd if=/dev/zero of=dummy_fs bs=1k count=20480 # 20480 = 20 * 1024
  

• Create an ext4 filesystem on your file:

  $ /sbin/mkfs -t ext4 dummy_fs       
  mke2fs 1.42.5 (29-Jul-2012)
  dummy_fs is not a block special device.
  Proceed anyway? (y,n) y
  ... # Output of mkfs
  

• Mount the filesystem image, create some dummy data on it and test the solution:

  # mkdir /tmp/testmount
  # mount -o loop dummy_fs /tmp/testmount
  # touch /tmp/testmount/{blah,bleh} # Create dummy data
  # ls /tmp/testmount
  blah bleh lost+found
  # umount /tmp/testmount
  # mountpoint /tmp/sexy_name &>/dev/null || mv /tmp/testmount /tmp/sexy_name
  # mount -o loop dummy_fs /tmp/sexy_name
  # ls /tmp/sexy_name # to ensure your data is intact:
  blah bleh lost+found
  

================================================================================== In GParted, Unmount it, and then you change the 'Label', which affects the given name and mount point. So if I changed this partition label to 'Data', it would have the label/name 'Data', and the mountpoint would become /media/wmobbs/Data.

Labels work best without spaces, and any special characters.

I also could do it in command line: If that does not work, change these lines in your /etc/fstab:

# /part was on /dev/sda7 during installation
UUID=47e6e0b1-0e57-4184-a378-375b9ce315c5 /part           ext4    defaults          0       2

to:

# /part was on /dev/sda7 during installation - mountpoint changed to /test
UUID=47e6e0b1-0e57-4184-a378-375b9ce315c5 /test           ext4    defaults          0       2

You can edit the file by running sudo nano /etc/fstab, then applying the above changes, and saving with Ctrl+O.
You then need to run sudo mkdir /test to create the needed folder - note that the folder needs to be empty.
You have to reboot for any changes to take effect