How to view disk space in Linux

 

I. df command
DF comes from the coreutils software package and comes with it during system installation. We can use this command to view the disk usage and the location where the file system is mounted. For example:

[Root @ localhost beinan] # DF-lH
Filesystem capacity in use available % mount point
/Dev/hda8 11g 6.0g 4.4g 58%/
/Dev/SHM 236 M 0 236 m 0%/dev/SHM
/Dev/sda1 56G 22g 35g 39%/mnt/sda1
We can see that the system is installed in/dev/hda8; there is also a 56 GB disk partition/dev/sda1 mounted in/mnt/sda1;
For other parameters, see man DF.

Ii. fdsik

Fdisk is a powerful disk operation tool from util-linux. Here we only talk about how to view the disk partition table and partition structure. The parameter-L is passed through the-l parameter, obtain the partition information of all the hard disks on the machine;

[Root @ localhost beinan] # fdisk-l
Disk/dev/hda: 80.0 GB, 80026361856 bytes
55 heads, 63 sectors/track, 9729 Cylinders
Units = cylinders of 16065*512 = 8225280 bytes
Device boot start end blocks ID system
/Dev/hda1*1 765 6144831 7 HPFs/NTFS
/Dev/hda2 766 2805 16386300 C w95 FAT32 (LBA)
/Dev/hda3 2806 7751 39728745 5 extended
/Dev/hda5 2806 3825 8193118 + 83 Linux
/Dev/hda6 3826 5100 10241406 83 Linux
/Dev/hda7 5101 5198 787153 + 82 Linux swap/Solaris
/Dev/hda8 5199 6657 11719386 83 Linux
/Dev/hda9 6658 7751 8787523 + 83 Linux

In the above blocks, it indicates the partition size, and the unit of blocks is byte. We can convert it to M. For example, if the size of the first partition/dev/hda1 is converted to m, it should be 6144831/1024 = 6000 m, that is, about 6 GB. In fact, it is not so troublesome. Let's take a rough look at moving the decimal point forward to three digits and we will know the approximate size;

System indicates the file system. For example,/dev/hda1 is in NTFS format;/dev/hda2 indicates a file system in FAT32 format ;.

In this example, we should pay special attention to the/dev/hda3 partition, which is an extended partition. It contains a logical partition, which is actually equivalent to a container; from her own hda5, hda6, hda7, hda8, hda9;

We also noticed that there is no hda4. Why? Why is hda4 not included in the extended partition? A disk can have up to four primary partitions; A hda1-4 is regarded as the primary partition; hda4 cannot be included in the extended partition, and the extended partition is also considered the primary partition; in this example, there is no hda4 partition, of course, we can set one of the partitions as the primary partition, but I didn't do this at the time;

Let's take a closer look at the statistics and see if there is space on this disk? Hda1 + hda2 + hda3 = actually partitioned volume, so we can calculate hda1 + hda2 + hda3 = 6144831 + 16386300 + 39728745 = 62259876 (B) and convert it into m units, the decimal point is shifted to three places, so the size of the partition that has been divided is about 62259.876 (M). In fact, the most accurate calculation is 62259876/1024 = 60800.67 (m ); the size of this disk is 80.0 GB (80026361856 bytes). In fact, the actual size is 78150.744 (M). Through a series of calculations, we can see that this hard disk still has space to use.
There is about 18 GB unpartitioned space;

Fdisk-l can list the number of all disks on the machine and all disk partitions. For example:
[Root @ localhost beinan] # fdisk-l
Disk/dev/hda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 Cylinders
Units = cylinders of 16065*512 = 8225280 bytes
Device boot start end blocks ID system
/Dev/hda1*1 765 6144831 7 HPFs/NTFS
/Dev/hda2 766 2805 16386300 C w95 FAT32 (LBA)
/Dev/hda3 2806 7751 39728745 5 extended
/Dev/hda5 2806 3825 8193118 + 83 Linux
/Dev/hda6 3826 5100 10241406 83 Linux
/Dev/hda7 5101 5198 787153 + 82 Linux swap/Solaris
/Dev/hda8 5199 6657 11719386 83 Linux
/Dev/hda9 6658 7751 8787523 + 83 Linux
/Dev/SDA: 60.0 GB, 60011642880 bytes
64 heads, 32 sectors/track, 57231 Cylinders
Units = cylinders of 2048*512 = 1048576 bytes
Device boot start end blocks ID system
/Dev/sda1 1 57231 58604528 83 Linux
 
We can know from the above that this machine has two hard disks, and we can also specify fdisk-L to view the partition of one of the hard disks;

[Root @ localhost beinan] # fdisk-L/dev/SDA
Disk/dev/SDA: 60.0 GB, 60011642880 bytes
64 heads, 32 sectors/track, 57231 Cylinders
Units = cylinders of 2048*512 = 1048576 bytes
Device boot start end blocks ID system
/Dev/sda1 1 57231 58604528 83 Linux

We can see from the above situation that there is only one partition in the/dev/SDA disk; The usage is almost;

We can also view/dev/hda's

[Root @ localhost beinan] # fdisk-L/dev/hda

3. view all disks and partitions on the current machine:

[Beinan @ localhost ~] $ CAT/proc/Partitions
Major minor # Blocks name
3 0 78150744 hda
3 1 6144831 hda1
3 2 16386300 hda2
3 5 8193118 hda5
3 6 10241406 hda6
3 7 787153 hda7
11719386 hda8
3 9 8787523 hda9
8, 0, 58605120, SDA
8 1 58604528 sda1

From: http://hi.baidu.com/carbens/blog/item/85872f893cee99b70e24446a.html