To exit fdisk without saving changes, use the q command. That being said, you should never practice on an important disk, as there are always risks. Use a spare external disk, or a USB flash drive instead.
The command p is used to print the current partition table. The output is something like this:. The total number of sectors in the partition. Multiply it by the sector size to get the partition size in bytes. In the example above, values are in gigabytes. On an MBR disk, you can have 2 main types of partitions, primary and extended.
One way to work around this limitation is to create an extended partition that acts as a container for logical partitions. You could have, for example, a primary partition, an extended partition occupying the remainder of the disk space and five logical partitions inside it. To create a partition, use the n command. By default, partitions will be created at the start of unallocated space on the disk.
You will be asked for the partition type primary or extended , first sector and last sector. For the first sector, you can usually accept the default value suggested by fdisk , unless you need a partition to start at a specific sector. See this example for the creation of a primary partition:. If you do not know how much free space there is on the disk, you can use the F command to show the unallocated space, like so:. To delete a partition, use the d command. In this case, this partition will be selected and deleted immediately.
Be aware that if you delete an extended partition, all the logical partitions inside it will also be deleted. Keep in mind that when creating a new partition with fdisk , the maximum size will be limited to the maximum amount of contiguous unallocated space on the disk. Say, for example, that you have the following partition map:.
Adding up the size of the unallocated space, in theory we have MB available. But see what happens when we try to create a MB partition:. That happens because the largest contiguous unallocated space on the disk is the MB block that belonged to partition 2.
Occasionally, you may need to change the partition type, especially when dealing with disks that will be used on other operating systems and platforms. This is done with the command t , followed by the number of the partition you wish to change. The partition type must be specified by its corresponding hexadecimal code, and you can see a list of all the valid codes by using the command l. Do not confuse the partition type with the filesystem used on it.
Although at first there was a relation between them, today you cannot assume this to be true. Linux partitions are type 83 Linux. Swap partitions are type 82 Linux Swap. The utility gdisk is the equivalent of fdisk when dealing with GPT partitioned disks. In fact, the interface is modeled after fdisk , with an interactive prompt and the same or very similar commands.
This is a bit hexadecimal number, assigned randomly when the partition table is created. Since there are 3. See the phrase Partition table holds up to entries? Because of this, there is no need for primary and extended partitions. The free space is listed on the last line, so there is no need for an equivalent of the F command from fdisk.
The command to create a partition is n , just as in fdisk. The main difference is that besides the partition number and the first and last sector or size , you can also specify the partition type during the creation. You can check a list of all the supported types by using the l command.
To delete a partition, type d and the partition number. Unlike fdisk , the first partition will not be automatically selected if it is the only one on the disk. To do this, simply use the s command.
For example, imagine a disk with the following partition table:. Unlike MBR disks, when creating a partition on GPT disks the size is not limited by the maximum amount of contiguous unallocated space. You can use every last bit of a free sector, no matter where it is located on the disk. GPT disks store backup copies of the GPT header and partition table, making it easy to recover disks in case this data has been damaged.
You can rebuild a corrupt main GPT header or partition table with b and c , respectively, or use the main header and table to rebuild a backup with d and e. Partitioning the disk is only the first step towards being able to use a disk. After that, you will need to format the partition with a filesystem before using it to store data.
A filesystem controls how the data is stored and accessed on the disk. The Extended Filesystem ext was the first filesystem for Linux, and through the years was replaced by new versions called ext2, ext3 and ext4, which is currently the default filesystem for many Linux distributions. The utilities mkfs. As such, they all have the same behavior and command line parameters.
Instead of using the command corresponding to the filesystem you wish to create, you can pass the -t parameter to mke2fs followed by the filesystem name. Here are some of the most significant ones. All of them also apply to mkfs. Sets the size of the data blocks in the device to SIZE , which can be , or bytes per block. Checks the target device for bad blocks before creating the filesystem.
You can run a thorough, but much slower check by passing this parameter twice, as in mkfs. Copies the contents of the specified directory to the root of the new filesystem. Danger, Will Robinson! This option will force mke2fs to create a filesystem, even if the other options passed to it or the target are dangerous or make no sense at all.
If specified twice as in -F -F it can even be used to create a filesystem on a device which is mounted or in use, which is a very, very bad thing to do. This label must be at most 16 characters long. This is a truly useful option that simulates the creation of the filesystem, and displays what would be done if executed without the n option. Good to check things out before actually committing any changes to disk.
Quiet mode. Useful when running mke2fs from a script. UUIDs are bit numbers in hexadecimal notation that serve to uniquely identify a partition to the operating system. This number is specified as a digit string in the format , meaning 8 digits, hyphen, 4 digits, hyphen, 4 digits, hyphen, 4 digits, hyphen, 12 digits, like DEACE.
Verbose mode, prints much more information during operation than usual. Useful for debugging purposes. Due to its performance and reliability features, it is commonly used for servers and other environments that require high or guaranteed filesystem bandwidth. Tools for managing XFS filesystems are part of the xfsprogs package. This package may need to be installed manually, as it is not included by default in some Linux distributions.
XFS filesystems are divided into at least 2 parts, a log section where a log of all filesystem operations commonly called a Journal are maintained, and the data section.
The log section may be located inside the data section the default behavior , or even on a separate disk altogether, for better performance and reliability. The most basic command to create an XFS filesystem is mkfs. For example: mkfs. As in mke2fs , mkfs. Here are some of the most common ones. The default value is bytes 4 KiB , the minimum is , and the maximum is 64 KiB. Parameters starting with -m are metadata options.
This enables better error detection and recovery from crashes related to hardware issues, so it is enabled by default. The performance impact of this check should be minimal, so normally there is no reason to disable it.
This will put the log section of the filesystem on the specified device, instead of inside the data section. The size can be specified in bytes, and suffixes like m or g can be used.
In this mode, mkfs. Similar to the -n parameter of mke2fs , will make mkfs. Both filesystems are handled by the same utility, mkfs. The FAT filesystem has important drawbacks which restrict its use on large disks.
Because of this, FAT filesystems are today more commonly used on small flash drives or memory cards up to 2 GB in size , or legacy devices and OSs that do not support more advanced filesystems. The most basic command for the creation of a FAT filesystem is mkfs.
Like other utilities, mkfs. Below are the most important ones. A full list and description of every option can be read in the manual for the utility, with the command man mkfs. If not specified, mkfs. Sets the volume label, or name, for the filesystem. This can be up to 11 characters long, and the default is no name. As it is well supported by all three major operating systems Windows, Linux and mac OS , it is a good choice where interoperability is needed, like on large capacity flash drives, memory cards and external disks.
The default utility for creating exFAT filesystems is mkfs. The most basic command is mkfs. Contrary to the other utilities discussed in this lesson, mkfs. They are:. This is a Bit hexadecimal number. If not defined, an ID based on the current time is set.
Specifies the first sector of the first partition on the disk. Entering n creates a new partition. In the command output, Partition number specifies the primary partition number. In the command output, First sector specifies the start sector. In the command output, Last sector specifies the end sector. UUID is the unique character string for disk partitions in a Linux system. When this parameter is set to 1 for the root partition, this parameter for other partitions must start with 2 so that the system checks the partitions in the ascending order of the values.
The system saves the configurations and exits the vi editor. Thank you for your feedback. Your feedback helps make our documentation better. View PDF. Scenarios In Linux, after the capacity expansion succeeded, the additional disk space needs to be allocated to an existing partition or a new partition. Based on your service requirements and disk condition, you can choose either of the following ways to allocate the additional disk space: Create a new partition services will not be interrupted.
Recreate an existing partition services will be interrupted. Prerequisites You have logged in to the server. You have attached the disk to the server , and the additional space has not been allocated. Checking File Systems on the To-be-expanded Disk Before expanding the disk capacity, check whether the file systems on the disk can be properly mounted.
Viewing the Partition Style Before allocating the additional space, query the current disk partition style. Use at your own discretion. Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command m for help :.
Information similar to the following is displayed: Command m for help : n All primary partitions are in use Adding logical partition 6 First sector , default :. Information similar to the following is displayed: Command m for help : w The partition table has been altered!
Calling ioctl to re-read partition table. The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe 8 or kpartx 8 Syncing disks.
These values will be used in the follow-up operations. Command m for help : d Selected partition 1 Partition 1 is deleted Command m for help :. Information similar to the following is displayed: Command m for help : n Partition type: p primary 0 primary, 0 extended, 4 free e extended.
There are two types of disk partitions: Choosing p creates a primary partition. Choosing e creates an extended partition. Information similar to the following is displayed: Select default p : p Partition number , default 1 :. Information similar to the following is displayed: Partition number , default 1 : 1 First sector , default :. This may take a while Improve this question. Add a comment. Active Oldest Votes. Improve this answer. Mubeen Iqbal 3 3 3 bronze badges. Sign up or log in Sign up using Google.
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