Mounting an NTFS RAID-0 stripe in Ubuntu 9.04 64 bit
 

Hi, so I have Windows installed and set up a RAID stripe a while back. I've got all my data there and I would like to access it via Ubuntu, mainly because I'd like to share it on my network (and not have to cut everyone in my house off) while I'm in Ubuntu. Both OS's are installed on separate disks.

I can't get the drive to mount. I keep getting this

"NTFS signature is missing.
Failed to mount '/dev/mapper/nvidia_facfcied': Invalid argument
The device '/dev/mapper/nvidia_facfcied' 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?"

Here are the steps I've taken (I already created the mount point /media/Z):

The drives I've highlighted are the ones that make up the RAID. The only thing that I can see is that Linux is not recognizing which drives make up that RAID...? Theres no mention anywhere that /dev/sdd and /dev/sdb form /dev/mapper/nvidia_facfcied.

Anyway, if anyone can help in anyway I'd really appreciate it. And honestly, I have the RAID backed up so I'm really willing to try anything at this point (short of formatting it because that wouldn't solve why its doing this in the first place).

Maybe you need to change this to the following (note the "1")
sudo mount -t ntfs-3g /dev/mapper/nvidia_facfcied1 /media/Z
If that doesn't work could you list the output of ls /dev/mapper?
BTW I take it you're using Vista or 7 given the GPT disk label...

Hi thanks for the reply! You're right I'm using Vista (sorry for not mentioning), I actually plan on installing 7 soon, I've already bought it just want to figure this out first. And nope, I've already tried adding the 1. This is the output

Heres is output of /dev/mapper

I'm really stumped... I'm about to try running live cd's of other distros to see if they mount the RAID, I'll let you know if that works.

What's interesting is that there are no partitions visible in your raid set, which maybe is normal for GPT; I don't know much about it as I'm still strictly 32-bit.

But maybe dmraid is only seeing the so-called protective mbr part of the disklabel. I suppose you could see if you have the latest version of dmraid or whether upgrading that makes any difference. I think 9.04 has rc15 and that you might need rc16.

I'm not sure what you mean by no visible partitions? Is there supposed to be something else in my /dev/mapper folder? The thing is, with mount manager it shows that the two drives are RAID members. I've attached a screen shot.

I have the rc15 version of dmraid, how do I upgrade it? When I go to Synaptics it doesn't allow me to mark for upgrade.

In Linux a storage devices that are going to be mounted have to be mounted based on the partition of the raw device. Mounting a raw device like /dev/sda can not be done. You have state the partition number after the raw device. The raw device is also stated as a device node. Your device node /dev/mapper/nvidia_facfcied is just a raw device. You will need a partition number like /dev/mapper/nvidia_facfcied1. If this is not shown, there could be an incompatible data buried in the RAID array. From what I read from the Internet, if there is space for your label, this can cause a problem. Disk labels with spaces are not valid. Try comply to DOS labels if you can. This means create a label with no more than eleven (11) characters. It is best to start out with a letter if you can.

The device mapper for RAID in Linux does not support all software RAID controllers and the reliability and stability is not good. It is best to not use this type of software RAID and go with hardware RAID. You can do this cheap with out adding software by using a hardware port multiplier from Addonics like the following.

http://www.addonics.com/products/hos...d4sr5hpmus.asp

Do not get the 5 port version because I do not think is not as fast and not compatible with Linux and your controller.

I do not recommend using NTFS if you are switching between Windows and Linux. FAT is better if you are switching between the two. If you need support for than 4 GB of file storage, use EXT2 or EXT3. There is EXT2 IFS that gives EXT2 support to Windows. Since EXT2 is known to the open source community very, very well compared to NTFS, so the chances of data corruption is much lower than using something like ntfs-3g to access NTFS. Nobody will ever know the difference except you will.

If the software RAID array is where Windows is stored, I strongly recommend do not access it in Linux with device mapper and with ntfs-3g. If you are going to use WINE to run Windows programs, it will hurt your Windows installation. Just do not attempt.

I have named the volume "Media" on Windows, so it definitely complies with the naming convention. It can't be that.


I'm using my motherboards RAID controller, its not a software RAID. My motherboard is a NVIDIA 680i SLI.


I may just have to do that, but I don't want to resort to it yet, I'd really like to solve this problem.

Well, when one mounts a raid set on dev/mapper/gaghajgkghwhatever and that raid set has an mbr instead of gpt, then usually the disk volumes/partitions show up in /dev/mapper as /dev/mapper/gadghdfgjhwhatever1 and 2. You HAVE to have at least one partition on an mbr disk, I presume it's the same for gpt.

You can go to the source at http://people.redhat.com/~heinzm/sw/dmraid/ It's pretty straightforward to build it from src.

Well, it really it works quite well and I've never had a problem, but to each is own, and I can't really argue with your advice, but that's not what the OP is looking for yet.

I don't think he was going to do that, just wanted to serve up the array. Wine apps need their own install, I agree.

That makes sense, but I don't know for sure this is my first time using Linux and in windows it shows up as one volume/partition... One thing I want to remind is that this array has NO operating systems, its strictly a media share.

I found this info here:

"GPT stores all partitions in a single partition table (with backup), so there's no need for extended or logical partitions. By default, 128 partitions are supported, although you can change the partition table size if the partitioning software supports such changes."

In regards to WINE, I'm not even sure what you mean. You're right, all I want to do is serve the array, I don't wish to install anything on it, or run anything from it. Like I said, Windows is not installed on this array, its strictly a media serving partition.

I'm going to install dmraid rc16 and see what happens. If that doesn't work I just found an article here that may be useful. I'll post back with my results, thanks guys for all your help really!! I've been searching left and right for a solution, hopefully we can figure it out :)

By the way I ran fdisk on the RAID and this is the results:

Not sure if this is useful or not, but I just installed Gparted and it recognizes the /dev/mapper/nvidia_facfcied partition :-) I think thats good news?

UPDATE:

ACTUALLY VERY GOOD NEWS... when I opened up Gparted, it like I said it shows /dev/mapper/nvidia_facfcied partition, but when I click on it, it shows (see attachment photo) two partition! However, i still ran into problems mounting, here are my results:

Now whats wrong???

I believe the problem here is GPT. I have once tried to use an Ubuntu LiveCD. (not sure which version) to mount a GPT partitioned disk. I found that the kernel that shipped with Ubuntu did not have GPT support compiled in at all. The symptom is exactly like yours, the device node for the raw disk was created, but not for the GPT partitions.

I gave up at this point & used my CentOS system instead which worked fine. I do remember reading somewhere that I could use the Ubuntu server kernel. (it was some time ago, so check this out first)

BTW, don't ever interact with GPT partitions using fdisk. You should only use parted when it comes to GPT.

BTW, just wanted to clarify this point of why people call this software raid. A raid controller is considered hardware only if there is a physical dedicated controller chip performing all RAID operations in hardware without using the PCs CPU for anything.

Most motherboard RAID controllers are actually controllerless, and they implement RAID in software, using a software interface in the BIOS, drivers in the OS and the CPU to perform the RAID operations. They seem to function like hardware RAID (by having a BIOS interface) but is in fact software RAID. Some like to call this "BIOS RAID" or "quasi-hardware RAID" but they are a form of software RAID where some parts of the interface are embeded in the hardware.

Sorry about that, just had to get that off my chest. :)

Thanks for clearing that up :)

So I guess I'm not going to have any luck mounting this thing then :(

Don't give up yet.

Well, this is good, you do need to mount partition 2 using mount, but the device hasn't been made yet by dmraid, which is why you need dmraid rc16, which I *think* supports GPT.

Opening up /dev/mapper/aghajkhgdwhatever with gparted doesn't create the /dev/mapper/ghadkghlksdhwhatever2, and as the message says, fdisk doesn't support GPT, but that doesn't matter, you don't neeed fdisk as long as the kernel is compiled to support GPT.

I'm pretty sure GPT/EFID is compiled into Ubuntu 9.04 c64 bit, so that isn't a worry, though clearly it would have been with the older ubuntu liveCD.

Actually I was reading about this some more, you can apparently try this:

to make your correct partition appear....so you may not need to update dmraid at all.

quoted from https://bugzilla.redhat.com/show_bug.cgi?id=500322

I love you

So here we go, this is what happened.

1. I needed to install kpartx
2. I ran the command which mapped the partitions for me :-) (below is my case scenario, any one else will have to replace "nvidia_facfcied" with their raid:
Once you have run the above command, you can go to /dev/mapper and you will notice two new partitions!

3. You now need to run the command to mount the partition to the mount point you define:

First to create mount point:
Next to mount it:
Take note of the "2" after "nvidia_facfcied". This is the partition, before I was trying to mount the RAW drive.

Again @mostlyharmless I can't thank you enough!!!!!! I've been trying to solve this for weeks!!!

You're welcome, glad you got it working.

this works, thank you