Live Resize of Logical Volume in RHEL/CentOS

The default installation of RHEL 6 and CentOS 6 will create separate LVM volumes for /home. This means much of your disk is allocated to /home when it could be used for something else. Keeping /home on a separate partition is a good idea for multi-user systems, but for machines that act as a service box, it may be wasted disk space. For example, here’s a system that has 50G partitioned for /home when it’s really not needed.

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$ df -h

2	Filesystem                  Size  Used Avail Use% Mounted on

3	/dev/mapper/vg_repo-lv_root 148G  113G   29G  80% /

4	tmpfs                       499M     0  499M   0% /dev/shm

5	/dev/sda1                   485M  156M  304M  34% /boot

6	/dev/mapper/vg_repo-lv_home 47G  181M   45G   1%  /home

To remove the logical volume that stores /home and add the free space to the root partition, follow these steps:

Note: Make sure you’re logged into the system at the console as a user whose homedir isn’t in /home. Logging in as root usually works.

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cd /

2	cp -Ra /home /home.bak  # Make a backup of home

3	umount /home

4	lvm lvremove /dev/vg_<hostname>/lv_home  # Remove the logical volume for home

5	lvm lvresize -l+100%FREE /dev/vg_<hostname>/lv_root  # Resize the root logical volume so it uses 100% of the now free space

6	resize2fs /dev/vg_<hostname>/lv_root  # Resize the filesystem to use the whole logical volume

7	mv /home.bak /home  # Restore the backup.

More Notes:

• This can be done on a live system as long as /home is not in use when you try to unmount it.
• You can also follow these steps to resize another logical volume if it has another name and isn’t in use.
• This may work with some adjustments on a RHEL/CentOS 5 system, I haven’t tried it though.
• you should definitly remove auto-mount information from /etc/fstab before rebooting the server.
• You’ll have to remove /home from /etc/fstab afterwards.

Live Partitioning in Windows 7 and 8

First of all go to ‘Start’ and then on the window that appears search for ‘Computer’ and then once you right-click on it another window opens and then you should navigate to the option ‘Manage’.

At once a new window will open entitled  ‘Computer Management’. In this new window click on ‘Storage’ and then go to ‘Disk Management’.

The completion of the second step will give you a view of all the drives present in your computer.

Among these select the one you want to partition. Then right-click on the selected drive and navigate to the option ‘Shrink Volume..’.

A new window should open in which the size of the drive before shrink will be mentioned and the available space to shrink will be mentioned , and in the next line you will be asked to enter the amount of space you want to shrink and this will be the size of the new partition.

Caution :The space you enter must be within the limit of the available space displayed above.

After entering the values click on the option ‘Shrink ” and wait for the process to complete. The time taken for the operation may be long depending upon the size of the disk and the space to be shrunk. Once the operation is completed a window appears showing unallocated space and the value is exactly the one you entered earlier. Select this unallocated space and on right clicking on it click on the option ‘New Simple Volume’.

A wizard will open up. Go through the wizard and fill in the values required. Usually the value needed to enter is the same one that you entered as the volume to be shrunk.

The drive newly created needs a letter to be assigned to it. Assign any letter of your choice as it does not make any difference.

A Format page will appear and in it carefully notice that the File System selected is ‘NTFS’ . After this is done enter a name for your drive and then click on ‘Next’ and then ‘Finish’.

You have reached your goal. You have partitioned your Hard Drive in Windows 7 without formatting your computer and without the use of any software.

**While the procedure works fine in Windows 7 Ultimate version, it does not work in Windows 7 home, starter or other versions properly if the number of partitions exceeds 4. That means if you try to create a new partition that is no. 5 in your hard disk, this process will not work otherwise it will work fine. So if you are in Windows 7 Home or starter edition, make sure that your total no of partition is three before you go for a new partition.**