parted command (start and end meaning)

Question

I am using the Linux parted command; I was using the 'mkpart' option which allows new partitions to be made, but I was confused when it asked me for the start and end.

What does 'start' and 'end' mean when talking about disks?

What's the need and use for a start and end?

Solution 1

This is to define the size of your partition and where it starts/end. If you want to have only one big partition, give 0% for start and 100% for end. Then for multiple partitions you can play with percents or sectors.

For instance if you want to split your disk in 2 partitions

• 0% 50% for the first one
• 50% 100% for the 2nd

should make the job

Solution 2

From the users manual for GNU parted:

start and end are the offset from the beginning of the disk, that is, the “distance” from the start of the disk.

This is also implied if not outright explained when you print the current partition table in the parted interface. Check the column heads in the table:

(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  1075MB  1074MB  primary  ext4         boot
 2      1075MB  53.7GB  52.6GB  primary               lvm

The start value indicates where you want the new partition to begin. It can be specified in several ways -- an absolute value for size/space, a percentage of the disk size, etc. -- and is measured from the beginning of the disk.

Comments

[printf]

ok i see, so could you give me an example of how i could calculate the start and end for a partition of 2GB?

[Sam Gwilym]

when i do 0% 50% - i see there is start at 1049kB and free space bettween 17.4kB and 1049kB. Why it happens?

[walnut_salami]

Note "0" and "0%" are not the same thing in parted. 0 and 100% gave me a warning about performance problems with partition size but 0% and 100% worked fine.