blkid --- to check what the partition specs are.

$ sudo blkid

It looks like you have an lvm2 partiton (fedora/redhat) in play. So there's special stuff for that.

$ sudo pacman -S lvm2
(or $ sudo apt-get install lvm2)

$ sudo lvscan
In the case of my fedora install on an SDHC card. And you mount that partition, not the /dev/ device.

$ sudo mount /dev/fedora/root /mnt/fedora

Which is on my /dev/sda2 partition according to $(cat /proc/partitions). To double mount it elsewhere.

$ sudo mount --rbind /mnt/fedora /home/user/fedora

Or something like that. YMMV.

installing ntfs-3g doesn't work ... seems

[root@server ~]# yum install ntfs-3g
Loaded plugins: changelog, fastestmirror, nethserver_events, presto, refresh-
: packagekit
Setting up Install Process
Loading mirror speeds from cached hostfile
* centos-base: ftp.cvut.cz
* centos-updates: ftp.cvut.cz
* elrepo: dfw.mirror.rackspace.com
* nethforge: mirror.framassa.org
* nethserver-base: mirror.framassa.org
* nethserver-updates: mirror.framassa.org
centos-base | 3.7 kB 00:00
centos-updates | 3.4 kB 00:00
centos-updates/primary_db | 2.0 MB 00:00
elrepo | 2.9 kB 00:00
nethforge | 3.6 kB 00:00
nethserver-base | 3.7 kB 00:00
nethserver-updates | 4.1 kB 00:00
nethserver-updates/primary_db | 60 kB 00:00
No package ntfs-3g available.
Error: Nothing to do

Sorry, don't get it. What should I do? Trying the above, it shows
[root@server ~]# pacman -S lvm2
-bash: pacman: command not found
[root@server ~]# apt-get install lvm2
-bash: apt-get: command not found
[root@server ~]# sudo apt-get install lvm2
sudo: apt-get: command not found
[root@server ~]# sudo lvscan
ACTIVE '/dev/VolGroup/lv_swap' [3.75 GiB] inherit
ACTIVE '/dev/VolGroup/lv_root' [1.82 TiB] inherit

query your repo for said item maybe written as a different name but same app. or you can install via source code which is a crazy fun thing to do!!!

But with most distros this is in repo or installed when installing system. because it is a well needed app, so that is crazy mad thin that you are getting "no package ntfs-3g" .. try query your repo using ntfs* to see what you get. then figure it out?

You need to enable the epel repository. http://fedoraproject.org/wiki/EPEL

yum install epel-release

I would install ntfs-3g and then disable the repository.

apt-get, yum, and pacman ??

these are seperate command calls for installing thing used by different/seperate Linux/GNU distos. Which you really need to know your system so you know which one to use. then just change the comamnds to match the needed results. this is a #1 thing to know when using Linux/GNU. My system uses the xbps command . so you see everyone is different in this respect. but for mounting it is not.

here is instructions on using apt-get and apt-cache

Pacman instructions

YUM instructions

Seems something is not working and I think this should be downloaded.

[root@server ~]# yum install epel-release
Loaded plugins: changelog, fastestmirror, nethserver_events, presto, refresh-
: packagekit
Setting up Install Process
Loading mirror speeds from cached hostfile
* centos-base: ftp.cvut.cz
* centos-updates: ftp.cvut.cz
* elrepo: dfw.mirror.rackspace.com
* nethforge: mirror.framassa.org
* nethserver-base: mirror.framassa.org
* nethserver-updates: mirror.framassa.org
No package epel-release available.

My fault, it does not work since you do not have the extras repositories enabled.

http://www.tecmint.com/how-to-enable...el-centos-6-5/

Wonderful, worked like a charm. Thank you!
So now I have the ntfs-3g installed. How could I proceed further please?

if you go over the past post you'll see that too has been covered. slow down take a breath, sip something liquid, then procceed ...

So went through the posts and it seems that I have to connect it to the Win computer and do the chkdisk as this is what I have:

[root@server /]# ntfs-3g /dev/sdb1 /share
ntfs_mst_post_read_fixup_warn: magic: 0xdc3006b3 size: 1024 usa_ofs: 60017 usa_count: 1848: Invalid argument
Record 0 has no FILE magic (0xdc3006b3)
Failed to load $MFT: Input/output error
Failed to mount '/dev/sdb1': Input/output error
NTFS is either inconsistent, or there is a hardware fault, or it's a
SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows
then reboot into Windows twice. The usage of the /f parameter is very
important! If the device is a SoftRAID/FakeRAID then first activate
it and mount a different device under the /dev/mapper/ directory, (e.g.
/dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation
for more details.

# mount /dev/VolGroup/lv_root /mnt/root

# dnf install lvm2
(or whatever the older Yum equivalent is. But you already have it installed.)

Not really what you need for NTFS filesystems. But one of those less than obvious things if you haven't been around a while. The ntfs3g and fuse stuff is what you need for ntfs.

http://www.tuxera.com/community/open-source-ntfs-3g/

sorry I don't get it ... I've did the mount of lv_root, but the only thing it does is that it mounts the same part of the internal drive to the folder root in the folder mnt. So it doesn't belong to the USB HDD.
lvm2 is installed and I don't know what to do with it.

Truly, I don't need the ntfs, but the thing is I have there data that I would need to get out. Once done I can format it to whatever else, but until then I just have to realise how to copy the data elsewhere.

if you got access to WINDOWS then hook it up to a windows copy or move all of your data to another drive then do with that drive whatever you wnat to, then you'd be done with it.

Anything about LVM at the moment is not relevant to mounting the USB drive. You can try running ntfsfix to see if it can fix your problem.

ntfsfix -n /dev/sdb1 ( The -n will only show what is wrong i.e. it will not do anything)