# NTFS signature is missing

## p5q

Hi,

Im new Gentoo user and i have problem with 1 of my partition. Its 2 TB NTFS partition

When i try to mount:

```
mount -t ntfs-3g /dev/sdb1 /mnt/raid

NTFS signature is missing.

Failed to mount '/dev/sdb1': Invalid argument

The device '/dev/sdb1' doesn't seem to have a valid NTFS.

Maybe the wrong device is used? Or the whole disk instead of a

partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?

```

fdisk -l

```

Device     Boot Start        End    Sectors  Size Id Type

/dev/sdb1        2048 3907035135 3907033088  1.8T  7 HPFS/NTFS/exFAT

```

First i check this https://forums.gentoo.org/viewtopic-t-866225-highlight-ntfs+signature+missing.html with no results.

Partition is not encrypted, it works with Windows 8.1 and Ubuntu LiveCD with no problem.

4.4.26-gentoo KDE Plasma version 5.8.3

Any help will be invaluable

----------

## NeddySeagoon

p5q,

Welcome to Gentoo. 

With the filesystem mounted in the Ubuntu LiveCD, what does 

```
df -T
```

say the filesystem type is?

The type shown in fdisk is generally not used by linux, There are two special cases I can think of 0xee and 0xfd.  

Its interesting that the partition that does not mount is /dev/sdb1.

Drive ordering in not deterministic in Linux and you have more than one drive, so its possible that under Gentoo, its not /dev/sdb.

In the Ubuntu LiveCD, run /sbin/blkid and make a note of the PARTUUID=, or even the filesystem UUID=.

Boot Gentoo and run /sbin/blkid and compare.  You can pass   PARTUUID=, or UUID= to mount.

Discovering the syntax is left as an exercise to the reader.

2TB is nearing the limit for an MSDOS partition table. Its not clear from your fdisk if you are using an MSDOS disk label or a GPT disk label.

If its GPT, check your kernel for GPT support.

----------

## p5q

So its MSDOS partition table, its there any chanse to mount that partition?

Generally its RAID 0 with 2 disk,

```
Disk /dev/sdb: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors

Units: sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 4096 bytes

I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disklabel type: dos

Disk identifier: 0x76f54ebd

Disk /dev/sdc: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors

Units: sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 4096 bytes

I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Device     Boot Start        End    Sectors  Size Id Type

/dev/sdb1        2048 3907035135 3907033088  1.8T  7 HPFS/NTFS/exFAT

```

GPT support in kernel is ok i check it twice https://wiki.gentoo.org/wiki/Handbook:AMD64/Installation/Kernel

Later on i will try put results from Ubuntu LiveCD

----------

## NeddySeagoon

p5q,

You can't mount one part of a raid0 set.  You need to start the raid set first.

Then you can mount the raid.

There are several ways thin can be done but you need both parts of the raid.

In Linux you either use dmraid, which gives you entries in /dev/mapper/ or you use mdadm which gives you /dev/mdX or possibly /dev/mdXpY if the raid is partitioned

Either way, you need kernel support.  Its harmless to have kernel support for both.

Notice that your drives are 1TB each but the partition table on /dev/sdb is 2TB, which won't fit onto either drive.

Instead the drives are used together, a 'chunk' of data on one drive, then a 'chunk' on the other.  There is no partition table on the other drive because of the 'chunking'

The partition table you have (on one drive) includes the space on the other drive.  All the 'chunks' are stacked end to end, for 2TB.

Linux will mount the filesystem only when it knows about the 'chunk stacking' beforehand.  This is the process known as assembling the raid.

It would be useful do post the output of Ubuntus dmesg.  That will tell us how it assembles the raid.

Its too big for a post.  Put it on a pastebin site and tell us the URL.

----------

## p5q

I spend 2 days to mount that partition and finally got it!  :Smile:  Thanks to Your advise!

1. Ubuntu LiveCD

```

/sbin/blkid

/dev/dm-1: LABEL="New Volume" UUID="DEB67130B6710A73" TYPE="ntfs" PARTUUID="76f54ebd-01"

/dev/sdb: TYPE="isw_raid_member

/dev/sdc: TYPE="isw_raid_member"

```

2. Copy UUID to gentoo  /etc/fstab

```

UUID=DEB67130B6710A73   /mnt/raid       ntfs-3g         defaults        0 0

```

----------

## NeddySeagoon

p5q,

/dev/dm-1 tells that its device mapper raid.  That's dmraid.

Since it just works, the kernel support you need must be there.

----------

