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DirtyMagic

Member

Registered: 2026-05-02

Posts: 2

[WORKAROUND]External drive mounts only read(not user-permition issue)

@archpc:~$ sudo fsck.vfat -r /dev/sda1
fsck.fat 4.2 (2021-01-31)
There are differences between boot sector and its backup.
This is mostly harmless. Differences: (offset:original/backup)
  65:01/00
1) Copy original to backup
2) Copy backup to original
3) No action
[123?q]? 1
Filesystem has 61032318 clusters but only space for 61032190 FAT entries.

The kernel apparently sees this as an error and mounts the drive as read only. There is a lot inside. I asked codex and it says i need to try fix it on widnows or cp the data to another drive and format it. Since i dont have windows installed and no spare 1tb should i try umount and force mount? or some other fix? i could use the drive just fine on windows and im sure if i install windows it will bulldoze inside no errors counted but could force mount hurt it somehow on linux?

  cd ~
  sudo umount /dev/sda1
  sudo mkdir -p /mnt/intenso
  sudo mount -t vfat -o rw,uid=$(id -u),gid=$(id -g),utf8,flush /dev/sda1 /mnt/
  intenso
  findmnt /mnt/intenso

should i do this?

Last edited by DirtyMagic (2026-05-02 23:19:32)

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seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,341

Re: [WORKAROUND]External drive mounts only read(not user-permition issue)

You're lacking 2048 kB (61032318 clusters in 1TB => 16kB/cluster and you're 128 short)

file -s /dev/sda
file -s /dev/sda1

It is generally not a good idea to write around in compromised filesystems - unless you know what happened you should not simply ignore this.
Does fsck not offer to fix this?
(nb. don't run fsck while the drive is mounted - ro or not)

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DirtyMagic

Member

Registered: 2026-05-02

Posts: 2

Re: [WORKAROUND]External drive mounts only read(not user-permition issue)

@archpc:~$ sudo file -s /dev/sda
  /dev/sda: DOS/MBR boot sector; partition 1 : ID=0xc, start-CHS (0x0,32,33),
  end-CHS (0x3ff,254,63), startsector 2048, 3907022017 sectors, extended
  partition table (last)
@archpc:~$ sudo file -s /dev/sda1
  /dev/sda1: DOS/MBR boot sector, code offset 0x58+2, OEM-ID "MSDOS5.0", sectors/
  cluster 64, Media descriptor 0xf8, sectors/track 63, heads 255, FAT (32 bit),
  sectors/FAT 476814, reserved 0x1, dos < 4.0 BootSector (0)
@archpc:~$ sudo fsck.vfat -n /dev/sda1
  fsck.fat 4.2 (2021-01-31)
  There are differences between boot sector and its backup.
  This is mostly harmless. Differences: (offset:original/backup)
    65:01/00
    Not automatically fixing this.
  Filesystem has 61032318 clusters but only space for 61032190 FAT entries.
 
Sadly even after i umount it fsck couldn't/wouldn't fix it so i paniced and took the coward's way into a friends windows laptop it autodetected the error on mount and the repair fixed it.The thing is that now i get write privilages by the kernel but fsck still shows the cluster problem so ill try to trim the files and put what i can on my pc and format the disk:)

Thanks for answering:D i installed arch first time this month and im pretty exited i promise as i become guru i'll help people too:D

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sudo pacman -Syu confidence
sudo pacman -Rns my_bad_decisions