Manage Partitions with GParted How-to

In the early days of computing and disk storage devices, file system and partition tools were very basic. You could create a partition, format the partition with a file system, and read and write data to the file system. For a long time, these basic tools were all that was available.

As disk storage grew, a need arose to be able to add and change partitions to better utilize the extra storage space. However, resizing a partition and file system was not possible.

Fortunately a number of people who believed in Free Software took it upon themselves to address these shortcomings. Some researched and developed tools to permit editing partitions. Others focused on tools to resize file systems without losing the contents. These tools were then published as Free Software with Open Source licenses, enabling all of us to use and share this software with our friends, family, and co-workers.

Many of these partition and file system tools are available only as text-based commands. To reach a wider audience, the GParted team saw a need for making these tools easier to use. This resulted in the creation of GParted, which provides a graphical interface to these partition libraries and file system tools.

In the recipes that follow, we will be using the GParted application from live media containing the GParted Live image.

GParted Live is a small bootable GNU/Linux distribution for x86- and x86_64-based computers that enables you to use all the features of the GParted application on Windows, GNU/Linux, and Intel-based Mac OS X computers.

Editing partitions has the potential to cause loss of data; there is always the possibility that something could go wrong due to software bugs, hardware failure, or power outage.

As such you are strongly advised to backup your computer system. Backup, test your backups, and backup again. Believe me, there might come a time when you will be glad you did this.

There are many different ways to backup your computer system. Some people make a complete image backup of their storage devices. Others such as myself backup the data only, with the realization that if something goes horribly wrong then I will need to re-install the operating system and applications from original media, in addition to restoring my valuable data. How you backup your computer information is up to you. The important thing is to make good backups.

Some partition editing actions inherently carry a higher risk for loss of data. In the recipes that follow we will indicate which actions have the highest risk.

This book is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.

And now with the necessities out of the way, let us get on with learning how to manage our partitions.

You will need a blank CD-R or CD-R/W disc, a CD burner, and CD writing software.

Follow these steps to create a Live CD:

Now, boot your computer using the Live CD:

The best way to use GParted is from Live media, such as GParted Live burned to a CD or written to a USB flash drive. When your computer is booted from the hard drive, the operating system has access to the partitions. To prevent this access and hence enable all supported partition editing actions, boot your computer using GParted Live removable media.

By downloading and using the latest stable release of GParted Live, you will have access to all the latest features and bug fixes.

In this example we used all of the default settings for GParted Live. However, several other options are available. For example if you choose the mode to load GParted Live to RAM then you will have access to your CD tray, which can be useful for making data backups to CD. Other options allow you to choose a different keyboard layout or select a different language.

Often, size alone can distinguish among different disk devices. Disk sizes can be a little tricky though because disk manufacturers use SI decimal prefixes (for example, 1 MB = 1,000,000 bytes), whereas GParted uses IEC binary prefixes (for example, 1 MiB = 1,048,576 bytes). The difference between these two methods becomes quite noticeable as the disk size becomes larger. For example, 160 GB is about 149 GiB. Hence the size of the disk device as shown in GParted will always be a lower number than the one reported by the disk manufacturer.

The device name is also useful to help distinguish among different disk devices. Device names vary by disk device as shown in the following table:

There is another handy way to select a disk device. You can select a disk device from the drop-down menu in the upper-left hand corner of the window.

Device containing data shown as unallocated

If you know the disk device contains data, but GParted shows the entire device as unallocated then there is no need to panic. It is possible there is a problem with the partition table.

Check for partition table problems by double-clicking on the unallocated disk device. This will bring up an information window, as shown in the following screenshot, which displays possible warnings about the device:

Two examples of warning messages that indicate partition table problems are as follows. A valid partition table:

• Can't have overlapping partitions

• Can't have a partition outside the disk

Resolution of these problems usually requires manually editing the partition table. The GParted website FAQ contains instructions on how to approach fixing these problems. See http://gparted.org/faq.php.

You can also seek help in the GParted forum. See http://gparted.org/forum.php.

Before picking a partition, it helps to know some background information about the primary types of file systems for each operating system. A brief summary of default file systems for operating systems is as follows:

Note that many operating systems support more than just the above listed default file systems. For example FAT16 and FAT32 are supported by many operating systems. As such, FAT16 and FAT32 are useful for sharing information between operating systems.

Typically drive letters in Windows and DOS correspond to partitions, except when the file system is not recognized by these operating systems.

With Windows and DOS, C: is often the first, and perhaps the only, partition on the disk device. Normally this partition is used in the boot process and has the boot flag set, as shown in the following screenshot. Note that only one partition on a disk device can have the boot flag set.

Many other partition layouts are possible. For example, some disk devices contain an Original Equipment Manufacturer (OEM) rescue partition at the start of the drive and hence the main operating system resides in a later partition.

When a partition is selected, the partition editing actions that are not available will be grayed out in the menus, and the corresponding buttons in the taskbar will be disabled.

Many partition editing actions require that the file system is not in use. Hence to be able to perform the widest range of editing actions, the file system must not be mounted, enabled as swap space, or in use in any other way.

Operating systems, such as Linux, can use many different types of file systems and do not require the boot flag to be set to boot the computer.

You can identify possible file system problems by following these steps:

You can attempt repair of file system problems by following these steps:

When GParted reads information from the device partitions and file systems, it makes notes of any problems encountered. The presence of these problems is indicated by an exclamation mark triangle icon beside the partition entry.

Examples of problems that occur are as follows:

Note that the GParted Live image contains all of the required software

While GParted operations are in the process of being applied, you can click on Details to open a details pane. Inside this pane you can click on each of the hierarchy of operations to expand and view more detailed information.

Checking and fixing NTFS file systems

An NTFS file system can become inconsistent if Windows is not cleanly shut down, for example, if the computer was powered off while it was running. To repair the NTFS file system, the preferred practice is to boot into Windows, open a command prompt (press Windows logo + R and enter cmd.exe) and use the check disk program by entering the following command:

chkdsk /f /r

Where the parameters indicate the following:

• /f: Fixes errors on the disk. The disk must be locked.

• /r: Locates bad sectors and recovers readable information. The disk must be locked.

Note that if chkdsk cannot lock the drive, a message appears that asks you if you want to check the drive the next time you restart the computer. Answer y to this question, as shown in the following screenshot:

After entering the chkdsk command, go through two reboot cycles to ensure that Windows has completely repaired the file system. A screen similar to the following is shown while chkdsk is running:

Before before performing this task, we highly recommend that you backup your data. This recipe involves moving the end of a partition boundary which is a moderate risk activity.

When you shrink a partition, the freed up space will be available immediately to the right of the partition. If this freed up space is required in a different location on the disk, you might need to consider moving other partitions, or resizing the start or end of the extended partition. Moving or growing partitions is covered in later tasks.

Remember that to perform operations on a partition, the partition must not be mounted or otherwise active. For operations on the extended partition, none of the logical partitions can be mounted or otherwise active. You can use the Partition menu to unmount, swapoff, or deactivate partitions as needed.

In the above steps, we moved the right-hand side of the partition, also known as the end of the partition. This instructs GParted to resize (shrink) the partition.

In this example, we left many options at the default values. If you wish to maintain compatibility with old operating systems, such as DOS, then you should set the Align to drop down list to the Cylinder setting. To ensure optimum space usage it is best to use the same alignment setting for all partitions on a disk device, normally MiB alignment with modern operating systems.

If you require more precise partition sizing, you can enter values or use the arrows in the New size, or Free space following spin boxes.

If you resize a partition containing an NTFS file system, you should reboot into Windows twice. This permits Windows to perform file system consistency checks.

The above steps instruct GParted to create a partition using all of the unallocated space. Further, the partition is formatted with a file system with the label specified (for example, MYDATA).

We left many options at the default values. Some other things to consider are:

One of the most common partition tables in use is the MSDOS partition table. This partition table has a limitation of four partition slots. The four slots can consist of up to four primary partitions, or up to three primary partitions and one extended partition. The extended partition is a special type of partition that can contain multiple logical partitions. If you wish to have more than four partitions in an MSDOS partition table, you need to create one extended partition. Inside the extended partition you can create more than one logical partition.

The choice of partition type is important because after a partition has been created, the partition type cannot be easily changed. For example, a primary partition cannot be easily turned into a logical partition, or vice versa. To change the partition type the partition must be deleted.

The three partition types use device numbers in the device name as follows:

Note that only one extended partition is permitted in an MSDOS partition table.

The following diagram depicts a primary partition (sda1), followed by an extended partition (sda2), which contains three logical partitions (sda5, sda6, and sda7).

The extended and logical partitions in this example were set up by first creating the extended partition sda2. Then, within the extended partition we created the logical partitions sda5, sda6, and sda7.

Before performing this task, we highly recommend that you backup your data. This task involves moving the start of a partition boundary, which is a high-risk activity.

One implication of moving a system partition is possibly breaking the boot process. The boot process can be repaired, so before moving a partition you should be prepared to repair the boot configuration. Specifically, you will need your operating system install media, and to be ready to check the GParted website for details on how to repair the boot process.

Before moving a partition, GParted reads all sectors to check for bad sectors. After a successful read of all sectors, GParted will begin copying sectors to their new location. This process can take a very long time since many sector read and write actions are required.

The move process is different for an extended partition. Since an extended partition is a container for logical partitions, it does not have its own file system. As such, moving an extended partition involves moving the partition boundaries only.

Moving can be combined with resizing a partition. Since the move operation is distinct from the resize operation, GParted will optimally determine the order of the resize and move steps to minimize the amount of data to be moved.

In this example, we left many options at the default values. If you wish to maintain compatibility with old operating systems, such as DOS, then you should set the Align to drop down list to the Cylinder setting.

If you require more precise partition movement, you can type in values or use the arrows in the Free space preceding, New size, or Free space following spin boxes.

If you resize a partition containing an NTFS file system, you should reboot into Windows twice. This permits Windows to perform file system consistency checks.

Before performing this task, we highly recommend that you backup your data. This task involves moving the end of a partition boundary which is a moderate risk activity.

Note that in order to perform actions on a partition, the partition must be unmounted. In the case of an extended partition, all of the logical partitions must be unmounted or otherwise inactive.

If there is no unallocated space immediately adjacent to the partition you wish to grow, then you might need to shrink, move, or delete other partitions to free up adjacent unallocated space.

The location of the unallocated space is important. To add space to a primary partition the unallocated space must be outside of the extended partition. To add space to a logical partition the unallocated space must be within the extended partition. Hence you might need to resize the extended partition, placing the unallocated space outside or inside the extended partition.

In the above steps, we expanded the right-hand side of the partition, also known as the end of the partition. This instructs GParted to resize (grow) the partition.

In this example, we left many options at the default values. If you wish to maintain compatibility with old operating systems, such as DOS, you should set the Align to drop down list to the Cylinder setting. If you require more precise partition sizing, you can enter values or use the arrows in the for New size, or Free space following spin boxes.

If you resize a partition containing an NTFS file system, you should reboot into Windows twice. This permits Windows to perform file system consistency checks.

As formatting a partition will overwrite the existing data, if you wish to keep the data you must first make a backup.

By selecting an existing partition and choosing format, you maintain the existing partition boundaries and the partition number. The process of formatting writes new file system metadata to the partition, which destroys the links to previously existing files. Often software recovery tools can be used to recover this data, but for our purposes all data in the partition is lost.

Formatting the partition with a new file system will overwrite the label and UUID used by the previous file system. The next two sections cover how to set a new label, and also the implications of the UUID change.

Connect a new disk device to your computer.

If you wish to write a new partition table to an existing device, be sure to first backup the data on the device because you will lose the partitions and the data.

For disk devices larger than 2 TB, you should consider using gpt instead of the default msdos partition table. More information on gpt and msdos partition tables can be found later in this recipe.

In this example we confirm that the disk device is missing a partition table, also known as a disk label. Then we write a new partition table to the disk device. At this point the disk device is now ready for new partitions to be created.

GParted supports many more types of partition tables. While the gpt and msdos partition tables are commonly used, others are also supported such as mac for MacIntosh computers, and amiga for Amiga computers. Note that Mac OS X uses a hybrid gpt and msdos partition table which is described later in the appendix at the end of this book.

GParted performs copy operations either by using file system tools or by copying sector by sector. For file systems such as NTFS and XFS, GParted uses native file system tools to perform the copy. For file systems lacking native file system copy tools, GParted performs a sector by sector copy.

The copied partition has the same UUID and label as the source partition. These duplicate UUIDs and labels can cause grief to operating systems because these values are supposed to be unique. To avoid such problems this task sets a new UUID and changes the label.

In this example, we left many options at the default values. If you wish to maintain compatibility with old operating systems, such as DOS, then set the Align to drop down list to the Cylinder setting.

If you require more precise partition sizing, you can enter values or use the arrows in the Free space preceding, New size, or Free space following spin boxes. Note that the destination partition size can be set larger than the source partition. For XFS file systems only, the destination partition can be set smaller than the source partition.

When you delete a partition you lose all of the data inside the partition. Hence, if you need any of the data, be sure to make a backup before deleting the partition.

Deleting a primary or extended partition removes the partition entry from the partition table.

Deleting a logical partition is different. Logical partitions are a special case because each logical partition has an Extended Boot Record (EBR) associated with the partition. The EBR is used to track the partition boundaries, and also to link to the next logical partition. Due to this linking nature, deleting a logical partition affects the device names of all higher numbered logical partitions. For example, if logical partition sda5 is deleted, then logical partitions sda6 and higher will have their partition number reduced by one (for example, sda6 will become sda5).

Changes in logical partition device names can adversely affect operating system boot process. As Windows can only be installed in a primary partition, the Windows boot process will not be affected. However, for operating systems that do permit booting from a logical partition, such as GNU/Linux, you might need to edit configuration files such as /etc/fstab, or other specific boot loader configuration files to restore the ability to boot.

Deleting a partition that is part of the boot process, such as the C: drive or a system reserved partition in Windows, might cause a computer to fail to boot. If your intention was to remove only one operating system, such as Windows, you might be surprised to find your other operating systems also fail to boot. If this occurs you should be able to restore the ability to boot using the original operating system install media.

The GParted website contains additional resources to help you restore the operating system boot. See http://gparted.org/faq.php.

Before before performing this task, we highly recommend that you backup your data. This task involves moving the start of a partition boundary, which is a high risk activity.

In order to add space to a partition, unallocated space must be available immediately adjacent to the partition. To free up this space, we use many of the recipes covered earlier.

First, we made unallocated space available by shrinking the logical partition where free space was available. Because the free space came from a logical partition inside an extended partition, and we needed to add the space to a primary partition, we had to edit three partitions to achieve the desired goal.

As mentioned in previous recipes, if you resize or move a partition containing an NTFS file system, then you should reboot into Windows twice to permit Windows to perform file system consistency checks.

Before performing this task, we highly recommend that you backup your data. This task involves moving the end of a partition boundary, which is a moderate risk activity.

This example uses several of the tasks that we covered earlier.

To make room for GNU/Linux we freed up unallocated space by shrinking the operating system primary partition. Then we created a partition with the ext4 file system, and another with linux-swap. The extra step to create a data partition in fat32 format adds flexibility because this partition can be shared with other operating systems.

Since the MSDOS partition table permits up to 4 primary partitions, we could have created the linux-swap and fat32 partitions as primary partitions too. However, this would prevent creating additional partitions in the future. That is why we chose to place these two file systems in logical partitions within an extended partition.

You are now ready to install GNU/Linux. Be sure to choose the manual partition option when installing your distribution. That way you can configure Linux to use the partitions you just created.

The following steps demonstrate how to choose a manual partition layout while installing Ubuntu 12.04.

All data stored in the fat32 partition will be available to both operating systems. In this example Ubuntu installation, the fat32 partition data is accessible in the top level /data directory. In Windows, it is accessible through a drive letter, such as the G: drive.

Remember from previous recipes that if you resize a partition containing an NTFS file system, you should reboot into Windows twice. This permits Windows to perform file system consistency checks.

Add the extra disk space to your RAID. As RAID configurations vary widely in the hardware and software used, we leave the task of increasing the storage capacity of the RAID to you.

When extra disk space is added to RAID, the extra space is not immediately available for partitioning. This is because a GUID Partition Table has a backup copy of itself stored at the end of the device. To remedy this situation, update the GPT so that the backup partition table is moved to the end of the RAID. Then the GPT is able to see all of the extra storage capacity.

If you do not fix the GPT, GParted will still show the additional disk space but you will be unsuccessful when applying operations that create or adjust partitions to use the additional disk space.

With today's larger disks devices and with support built into modern operating systems, GPT is taking over from the msdos partition table. One of the main reasons is that an msdos partition table cannot access partitions larger than 2 TB, or partitions that start beyond the first 2 TB of the disk device. Another reason is that GPT supports 128 primary partitions, whereas msdos is limited to 4 primary partitions.

Note that RAIDs that use msdos partition tables do not require this repair step because there is only one copy of the msdos partition table, which is located at the start of the disk device.

While we hope it never happens to you, if you lose a partition by accidental deletion or by some other method and you do not have a backup of your data, this recipe may help you to rescue data from your partition. To improve the chances of rescuing data, do not write to the partition table by creating new partitions or resizing existing partitions.

This data rescue method supports searching for the following file systems: ext2, fat16, fat32, ntfs, reiserfs, and jfs. If you lost a different file system, then see the Restoring a deleted partition section at the end of this recipe.

For this example, we started with a small 100 MB disk device with two partitions containing NTFS file systems. To demonstrate rescuing data, we deleted the second partition (approximately 15 MiB NTFS). The following image shows the partition layout in GParted prior to partition deletion:

To find file systems on disk devices, GParted uses another application called gpart (not to be confused with GParted) to scan the entire disk device for recognizable file systems.

If file systems are found by this utility, GParted displays a window with an entry for each partition file system found. By clicking the View button beside the entry, GParted will try to mount the partition in read-only mode. If the mount is successful, you can manually navigate to the mounted file system. Moreover, you can manually mount additional storage in order to store a copy of the data from the lost partition.

When you close the window with the list of found file systems, these temporarily mounted partitions are unmounted.

The gpart application used to scan the disk device is not infallible. In some instances, gpart will fail to recognize common file systems. If this happens, you will not be able to use GParted to rescue your data.

Unfortunately the gpart application has not been actively maintained, leaving it behind current advancements in partition tables and file systems. As such, gpart suffers from the following limitations:

With these limitations in mind, if you have lost a partition with valuable data, it might still be worth the effort to attempt to rescue the data using the steps in this recipe.

Mac OS X uses a hybrid partition table scheme that is a combination of GPT and MS-DOS partition tables. This hybrid partition table scheme is non-standard. When you edit the hybrid partition table, GParted will make the GPT align with GPT standards by writing a single protective entry in the MS-DOS portion of the hybrid partition table. This causes the partition entries in the MS-DOS portion to be lost, and prevents some operating systems from booting, such as 32-bit versions of Windows.

Fortunately these MS-DOS partition entries can be recreated from the GPT partition entries. When you finish editing Mac OS X partitions, open a terminal window and enter the following command:

sudo gptsync /path-to-disk-device

where /path-to-disk-device is the disk device you just edited (for example, /dev/sdc).

The gptsync command will copy the GPT partition entries that are below the 2 TB MS-DOS limit into the MS-DOS portion of the hybrid partition table scheme.

If you wish to repurpose your iPod for use as a RockBox music player, or as a portable GNU/Linux drive, you may wish to edit your iPod partition table. Before editing iPod partitions, you should be aware of the following unusual partition configuration.

Some iPods have a proprietary firmware partition at the start of the device. This partition ID is set to type 0 (zero). A type 0 partition ID usually indicates the partition is empty. In this situation, GParted treats the partition as empty and might use the partition table entry, or overwrite the partition while you are editing iPod partitions. This can overwrite the proprietary firmware, causing your iPod to cease to function as the manufacturer intended.

To prevent overwriting this type 0 partition we recommend that you use the following high-level steps:

Following is a example listing of an iPod partition table with a type 0 partition:

user@debian:~$ sudo fdisk -l /dev/sde
Note: sector size is 2048 (not 512)

Disk /dev/sde: 8120 MB, 8120172544 bytes
250 heads, 62 sectors/track, 255 cylinders
Units = cylinders of 15500 * 2048 = 31744000 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sde1               1           3       92876    0  Empty
/dev/sde2               4         255     7812000    b  W95 FAT32
user@debian:~$

Assuming the iPod is recognized as device /dev/sde, the steps to use fdisk to change the partition id type are as follows:

user@debian:~$ sudo fdisk /dev/sde

Command (m for help): t
Partition number (1-4): 1
Hex code (type L to list codes): 83
Changed system type of partition 1 to 83 (Linux)

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
user@debian:~$

Use similar steps, as shown above, to set the type back to 0 (zero), instead of 83.

Oftentimes, virtual machine (VM) software provides the ability to add more space to virtual disk drives. However, adding more space does not increase the size of the virtual disk drive partitions. This is where GParted can help. The high-level steps are as follows:

Using these steps, you can avoid creating a new VM with larger virtual disk drives. This will save time and effort needed to reinstall the operating system and applications, restore the data, and configure the system.

There are several resources available to help you with GParted:

For additional information on GParted, see http://gparted.org.

The practical applications of GParted are numerous since GParted can be used on a wide variety of disk devices. Searching the Internet reveals many ways people have used GParted to accomplish their goals.

Some of the other uses of GParted include:

The list of uses for GParted continues to grow.

With these many uses in mind, we hope that this book has empowered you with the knowledge and tools to manage partitions with GParted.