How to view the cluster size of an NTFS file system?

exerceo · 02-20-2024, 03:41 AM

For other file systems, the "fsck" tool can be used with the -n (read-only) and -v (verbose) switches, to show the cluster size. For example:

Code:

fsck.exfat -n -v /dev/mmcblk0p1

However, given that NTFS is a proprietary Microsoft file system, support by operating systems outside Windows relies on reverse-engineering and has therefore been limited for a long time. File system checking is even more difficult to implement than normal reading and writing, so appears to be no "fsck.ntfs" so far.

Is there any tool which just shows the cluster size of NTFS?

(Yes, I know, "NTFS file system" is a redundant acronym, but I have to write it like this for clarity.)

syg00 · 02-20-2024, 05:12 AM

If you want control, don't use proprietary on FOSS.
You want to know details, go look on Windows

pan64 · 02-20-2024, 05:51 AM

looks like this is the current situation: https://wiki.archlinux.org/title/NTFS

lvm_ · 02-20-2024, 06:00 AM

ntfsinfo should do it https://linux.die.net/man/8/ntfsinfo

exerceo · 02-20-2024, 09:23 AM

Quote:

Originally Posted by syg00

If you want control, don't use proprietary on FOSS.
You want to know details, go look on Windows

That's understandable for complicated stuff like file system repair (chkdsk, fsck), but something as simple as seeing the cluster size should be doable on Linux.

I am trying to use as little proprietary stuff as possible. Unfortunately, much of the world is stuck with Windows and MacOS. Android OS only recently implemented read-only NTFS support.

Thankfully, external HDD and SSD manufacturers have switched from NTFS to exFAT. Until the mid-2010s, external hard disks were commonly pre-formatted with NTFS. Why not FAT32? Because 4 GiB.

Now that Microsoft has open-sourced exFAT (thanks alot!), it has become the de-facto standard for file systems without a garbage 4 G file size limitation.

Quote:

Originally Posted by pan64

looks like this is the current situation: https://wiki.archlinux.org/title/NTFS

Interesting article (I was already aware of it), however, it has no mention of cluster sizes.

Quote:

Originally Posted by lvm_

ntfsinfo should do it https://linux.die.net/man/8/ntfsinfo

Haven't tried it yet. I will check it out. Thanks, lvm_.

kreemoweet · 02-21-2024, 06:44 PM

The cluster size of an NTFS filesystem is one of the filesystem parameters found in the VBR (Volume Boot Record), and is pretty well documented and discussed, such as
at http://kcall.co.uk/ntfs/index.html.

pan64 · 02-22-2024, 01:37 AM

Quote:

Originally Posted by exerceo

Interesting article (I was already aware of it), however, it has no mention of cluster sizes.

But it contains a link to the official documentation where you can find related information (especially paragon have not yet developed any tools for that).
Anyway the other way is to use the ntfs-3g tools, like ntfsinfo (which was mentioned too). It is documented here: https://github.com/tuxera/ntfs-3g (but I think you know that)

rknichols · 02-22-2024, 08:28 AM

The "file" command will report the sectors/cluster for an NTFS volume. Example (line breaks added):

Code:

# file -s /dev/sda2
/dev/sda2: DOS/MBR boot sector, code offset 0x52+2, OEM-ID "NTFS    ",
 sectors/cluster 8, Media descriptor 0xf8,
 sectors/track 63, heads 255, hidden sectors 206848,
 dos < 4.0 BootSector (0x80), FAT (1Y bit by descriptor);
 NTFS, sectors/track 63, sectors 143903295,
 $MFT start cluster 786432, $MFTMirror start cluster 2,
 bytes/RecordSegment 2^(-1*246), clusters/index block 1,
 serial number 0e6f00230f002080f; containsMicrosoft Windows XP/VISTA bootloader BOOTMGR