How to view unallocated free space on a hard disk through terminal

Question

I want to view the unallocated free space on my hard disk through terminal  I ve burned my brains searching the internet for a possible solution  but all in vain   I used all sorts of commands like df  du  fdisk  parted  etc  It tells me about the disks that are mounted and unmounted  but what about the unallocated space that I ve left free   Of course I can view it using the  Disk Utility  app provided by Fedora  but since I LOVE being in the terminal I d like to view in it   Can anyone please help me with a solution

User · Answer

In addition to all the answers about how to find unpartitioned space, you may also have space allocated to an LVM volume but not actually in use. You can list physical volumes with the pvdisplay and see which volume groups each physical volume is associated with. If a physical volume isn't associated with any volume group, it's safe to reallocate or destroy. Assuming that it it is associated with a volume group, the next step is to use vgdisplay to show your those. Among other things, this will show if you have any free "physical extents" — blocks of storage you can assign to a logical volume. You can get this in a concise form with vgs:

$ sudo vgs
  VG     #PV #LV #SN Attr   VSize   VFree
  fedora   1   3   0 wz--n- 237.46g    0

... and here you can see I have nothing free. If I did, that last number would be bigger than zero.

This is important, because that free space is invisible to du, df, and the like, and also will show up as an allocated partition if you are using fdisk or another partitioning tool.

User · Answer

I had just the same trouble with fedora 26 and LVM partitions  it seems I forgot check something during the installation  So   my 15G root directory has been increased to 227G like I needed   I posted the steps I followed here   resize2fs  Bad magic number in super-block while trying to open  0   df -h  Filesystem               Size  Used Avail Use  Mounted on devtmpfs                 1 9G     0  1 9G   0   dev tmpfs                    1 9G     0  1 9G   0   dev shm tmpfs                    1 9G  824K  1 9G   1   run tmpfs                    1 9G     0  1 9G   0   sys fs cgroup  dev mapper fedora-root   15G  2 1G   13G  14    tmpfs                    1 9G     0  1 9G   0   tmp  dev md126p1             976M  119M  790M  14   boot tmpfs                    388M     0  388M   0   run user 0  1    vgs    VG      PV  LV  SN Attr   VSize   VFree      fedora   1   2   0 wz--n- 231 88g 212 96g  2    vgdisplay    --- Volume group ---   VG Name               fedora   System ID   Format                lvm2   Metadata Areas        1   Metadata Sequence No  3   VG Access             read write   VG Status             resizable   MAX LV                0   Cur LV                2   Open LV               2   Max PV                0   Cur PV                1   Act PV                1   VG Size               231 88 GiB   PE Size               4 00 MiB   Total PE              59361   Alloc PE   Size       4844   18 92 GiB   Free  PE   Size       54517   212 96 GiB   VG UUID               9htamV-DveQ-Jiht-Yfth-OZp7-XUDC-tWh5Lv  3    lvextend -l  100 FREE  dev mapper fedora-root    Size of logical volume fedora root changed from 15 00 GiB  3840 extents  to 227 96 GiB  58357 extents     Logical volume fedora root successfully resized   4   lvdisplay  5   fd -h  6    xfs growfs  dev mapper fedora-root  meta-data  dev mapper fedora-root isize 512    agcount 4  agsize 983040 blks                                  sectsz 512   attr 2  projid32bit 1                                  crc 1        finobt 1 spinodes 0 rmapbt 0                                  reflink 0 data                             bsize 4096   blocks 3932160  imaxpct 25                                  sunit 0      swidth 0 blks naming    version 2              bsize 4096   ascii-ci 0 ftype 1 log       internal               bsize 4096   blocks 2560  version 2                                  sectsz 512   sunit 0 blks  lazy-count 1 realtime  none                   extsz 4096   blocks 0  rtextents 0 data blocks changed from 3932160 to 59757568   7   df -h  Filesystem               Size  Used Avail Use  Mounted on devtmpfs                 1 9G     0  1 9G   0   dev tmpfs                    1 9G     0  1 9G   0   dev shm tmpfs                    1 9G  828K  1 9G   1   run tmpfs                    1 9G     0  1 9G   0   sys fs cgroup  dev mapper fedora-root  228G  2 3G  226G   2    tmpfs                    1 9G     0  1 9G   0   tmp  dev md126p1             976M  119M  790M  14   boot tmpfs                    388M     0  388M   0   run user 0   Best regards

User · Answer

when you cut you disk in partitions by fdisk you may be careful so as not to left gaps with free space  So command automatically align partitions and you ll get some gaps between parts  There are many articles in net why need to do so  The reason is that it gives solution with less errors  That was many years ago  Now I don t know is there errors occurs if you do all without any gaps  But first  You may do so if you don t allow alignment you sen begin of the next part end previous 1  But is first part begins always with 2048 sector  So call expert part you may shift it to 0  But strongly recomended to do so if you plan to boot from this disk  If only for data you ll  gain 1 Mb additional disk space  This is an MBR space  If you plan to install OS on this disk you don t use GPT partition type  Also it s more suitable not all OS see GPT parts of disks  But some see them  If you don t sure it use msdos  While format the block size is 4096 bytes logical  physical one is 512 bytes  I don t do so but you may set block size 512 too  There was many discussion about that  It s lead to disk errors  But you ll give some free disk space too especially when you have many small size files  You disk will fill more compactly   And if you give already partitioned disk with filled them with data and maybe installed OS you maybe want to do so  it was very problems to do  But is possible for Linux  For Windows no    You must save backup and mbr too  write UUID every part then use fdisk and format as setting right UUID and LABEL for every part restore mbr with dd command and if you don t do any wrong all will be work as before but without any gaps

User · Answer

You might want to use the fdisk -l  dev sda command to see the partitioning of your sda disk  The  free space  should be some unused partition  or lack of

User · Answer

Just follow below    find out the dev type  whether it is  dev sda  dev hda  dev vda etc  look for vi  etc fstab and find out the mounted partisions and there UUIDs etc say  your harddisk is labeled as  dev sda and you know number of  dev sda under df -hT   then you need to find out remaining  dev sda  right   so   fdisk -l  dev sda  will give the ALL  dev sda  and you will find for example   dev sda4 or  dev sda5  then find out UUIDs of mounted partisions and those are not listed in  etc fstab are the ones you can format and mount   just follow this up  a world to wise is sufficient

User · Answer

This is an old question  but I wanted to give my answer as well   Since we re talking about free available space  we should talk about sectors  since no partitioning or sizing of sectors is done   For us human beings this doesn t make much sense  To have human-readable information we must translate this number into bytes  So  we have a disk already partitioned and we want to know how much space we may use  I personally don t like the parted solution because my brain-memory for commands is already taken  There is also cfdisk  which gives you free space  But I think fdisk is the quickest solution  it s plain and simple  with nothing to install  execute fdisk  dev sdx and then enter v into the interactive shell  It will gives you the number of sectors still free   2004-54-0  17 03 33  root minimac     gt  fdisk  dev sda Welcome to fdisk  util-linux 2 23 2      Command  m for help   v Remaining 1713 unallocated 512-byte sectors   We still have 1713 sectors at 512 bytes each  So  because you love terminal  in 2012  who knows now   we do echo     1713 512  1024  k  which is 1713 sectors multiplied for 512 bytes  divided by 1024 to have KB   which gives 856k   not even 900 KB   and I need another disk

User · Answer

A simple solution to the answer   parted  dev sda   Display the help on unit  Then toggle it to the units you want   To show free space on the device  use   print free

User · Answer

To see in TB     parted  dev sda unit TB print free   grep  Free Space    tail -n1   awk   print  3    To see in GB     parted  dev sda unit GB print free   grep  Free Space    tail -n1   awk   print  3    To see in MB     parted  dev sda unit MB print free   grep  Free Space    tail -n1   awk   print  3    To see in bytes     parted  dev sda unit B print free   grep  Free Space    tail -n1   awk   print  3    To see in       parted  dev sda unit     print free   grep  Free Space    tail -n1   awk   print  3    To see in sectors     parted  dev sda unit s print free   grep  Free Space    tail -n1   awk   print  3    Change  dev sda to whatever device you are trying to find the information about   If you are using the result in any calculations  make sure to trim the trailing characters

User · Answer

The simplest way to show unallocated free space in a single command     sudo sfdisk --list-free  dev sdX    Add the --quiet option if you don t need the extra info about sector size  etc

User · Answer

While using the disk utility graphically  it shows disk space used by all filesystem and it uses commands in the terminal such as df -H  In other words  it uses powers of 1000  not 1024   Note  there is difference between -h and -H    While also finding the unallocated space in a hard disk using command line    fdisk  dev sda will display the total space and total cylinder value    Now check the last cylinder value and subtract it from the total cylinder value   Hence the final value   1000 gives you the unallocated disk space   Note  the cylinder value shows up in df -H as a power of 1000 or it might also show up using df -h  a power of 1024

User · Answer

If you need to see your partitions and or filers with available space  mentioned utilities are what you need  You just need to use options   For instance  df -h will print you those information in  human-readable  form  If you need information only about free space  you could use  df -h   awk   print  1    4

User · Answer

The filesystem size can be different from the patition size  To repair you need to do this     df -h   see what is the name of the partition say  dev sda3     resize2fs  dev sda3

User · Answer

Use GNU parted and print free command   root sandbox    parted GNU Parted 2 3 Using  dev sda Welcome to GNU Parted  Type  help  to view a list of commands   parted  print free Model  VMware Virtual disk  scsi  Disk  dev sda  64 4GB Sector size  logical physical   512B 512B Partition Table  msdos  Number  Start   End     Size    Type      File system  Flags         32 3kB  1049kB  1016kB            Free Space  1      1049kB  256MB   255MB   primary   ext2         boot         256MB   257MB   1048kB            Free Space  2      257MB   64 4GB  64 2GB  extended  5      257MB   64 4GB  64 2GB  logical                lvm         64 4GB  64 4GB  1049kB            Free Space

[linux] How to view unallocated free space on a hard disk through terminal

Examples related to linux

Examples related to terminal

Examples related to fedora

Examples related to hard-drive