HOW-TO make an external disk usable for PC and NAS

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22-01-2007, 20:53
mumsoft

HOW-TO make an external disk usable for PC and NAS

Hi,

For my final instructions look below for the message "HOW-TO make an external disk usable for PC and NAS - revisited"

I posted my experience in http://wl500g.info/showpost.php?p=48361&postcount=5
You can read there how I got an external usb-disk working for both the WL-700Ge AND my pc. Maybe this information needs some refinement, so I'm wondering what others can say about it.
What I did not tell is that I first had formatted the disk with a primairy FAT partition. That gave it a valid partion table. After that I let the WL-700gE do it's tricks with it, to make it a volume and to define a share on it. But I did this weeks ago and I'm not very sure about the details.
Now I have the pleasure to be able to use the disk wherever I plug it in. :D
Maybe you need a Knoppix DVD or a Linux RescueCD to do this trick if you use Windows.

Any comment is welcome.

Marc
30-01-2007, 16:36
saprize

Hi,
Is your external usb drvie a mirror to the internal drive? I'm using the usb to mirror the internal drive. But, I have no idea how to recover the data from the usb drive. I read your post but didn't really understand. I have a Linux machine but cannot mount the usb drive formatted by the WL700.
31-01-2007, 13:49
mumsoft

Quote:

Originally Posted by saprize

Hi,
Is your external usb drvie a mirror to the internal drive? I'm using the usb to mirror the internal drive. But, I have no idea how to recover the data from the usb drive. I read your post but didn't really understand. I have a Linux machine but cannot mount the usb drive formatted by the WL700.

My external drive is no mirror, but it could have been.
But to prepare an external disk as I did for use at both a PC and this white NAS, you will have to start with an empty disk, or don't mind that you will lose everything on it.
I will try to repeat my recipe with another disk, and exactly describe what the steps are, because my first successful attempt has been spread out over several weeks.

If your drive acts as a mirror and has been formatted by the WL-700gE itself, you won't be able to mount it on your pc. But, as I have described previously elsewhere http://wl700g.info/showthread.php?t=7663 , you can replace it with the internal drive if that fails, and move on.

But, if you want it to behave as a mirror AND be able to use/see it at your pc, you have to follow my feeble steps, which I will repeat in the near future.
Then you will have to let the NAS rebuild your newly formatted mirror, and that takes several hours. Be prepared. Of course, I you don't mind you could try it yourself now.

Marc
31-01-2007, 19:31
saprize

I would prefer the ability to see the contents of the external drive in windows and/or linux. That would be more of a comfort that I wont lose my data. I don't mind erasing the mirror drive and starting over if it gives me this ability. Since I don't trust the mirror I'm still using other backup methods.

Thanks for your help. I will await the exact steps and give it a try.
16-02-2007, 22:15
mumsoft

HOW-TO make an external disk usable for PC and NAS - revisited

Quote:

Originally Posted by saprize

I would prefer the ability to see the contents of the external drive in windows and/or linux. That would be more of a comfort that I wont lose my data. I don't mind erasing the mirror drive and starting over if it gives me this ability. Since I don't trust the mirror I'm still using other backup methods.

Thanks for your help. I will await the exact steps and give it a try.

I have repeated the steps successfully. But I did not succeed when I started with a NAS- used disk. So, be aware that you will LOOSE EVERYTHING on the disk you prepare this way. Furthermore, you need Linux, for instance a bootable Knoppix cd.

1 - prepare the disk at your pc. Make sure it gets 4 primairy partitions, FAT-formatted. These don't have to span the whole disk, and maybe not all 4 are needed, but with 4 it works. You can do this with Windows or Linux or what you have.

2 - attach the disk at the WL-700gE. It will be seen as a Foreign Disk in disk management. Now, erase the disk, and format it, and give it a usefull name, say 'testdisk'. Now, remove the disk with the button: "Savely Remove Disk"

3 - attach the disk at your Linux pc. Open a shell and use fdisk as root. If the disk is called /dev/sda, as in my case type this:
fdisk /dev/sda
It is important that you don't see a message about a missing msdos signature, but if you performed step 1 the right way, it should not pop up.
You will notice that there are no partitions. The 4 partitions of step 1 are gone. Type p to verify this.
Create a new partition (n) that is primairy (p) and is the first (1). Use the whole disk for this, which is default.
You will see something like:
Device Boot Start End Blocks Id System
/dev/sda1 1 9963 80027766 83 Linux
Now change the type (t) in (fd): Linux raid auto-detection
Finally, write (w) this to the disk.

4 - attach the disk to the WL700gE. It will be seen as the "testdisk", but still unallocated. Now create a volume on it, say "testvolume", and create a share, say "testshare". Put some stuff from your pc on this share. Again, remove the disk with the button: "Savely Remove Disk".

5 - attach the disk at your Linux pc. Open a shell with root access, and mount the disk with:
mount /dev/sda1 -t reiserfs /mnt/test
in which /dev/sda1 is the name of the disk-partition and /mnt/test is a directory.
It will take some heavy seconds... and yes... type
ls -all /mnt/test (sometimes dir /mnt/test is the same)
and you will see all that you put on it in step 4.

Last remarks
- I did not try it, but making the disk a mirror should pose no problem, but takes several hours.
- I tried, oh yes, again and again, to use this procedure on a used disk without step 1, because it would be so nice if you could prepare your external disk without losing the data. But that seems impossible. I will ask some advice though, so maybe I come with some sort of a solution in the future.
- I have screenshots for every step, but I have to combine them for this forum. I did not want to wait any longer, so here are the steps in plain English.

Marc :D
17-02-2007, 14:41
saprize

It worked!

Thanks Marc (Mumsoft).

I can see the contents of the mirror on my Linux machine. I followed all of the steps but on step 4 I created a mirror in the WL700ge. In step 5, I needed to mount from /dev/sdb1.

Not sure why it works or why step 1 is needed. I cannot see the drive in Windows, but that's okay. At least if the internal drive fails I can connect the usb drive to the Linux machine and recover the data on the mirror.

Now I can sleep at night.
17-02-2007, 20:52
mumsoft

Quote:

Originally Posted by saprize

Thanks Marc (Mumsoft).

I can see the contents of the mirror on my Linux machine. I followed all of the steps but on step 4 I created a mirror in the WL700ge. In step 5, I needed to mount from /dev/sdb1.

Not sure why it works or why step 1 is needed. I cannot see the drive in Windows, but that's okay. At least if the internal drive fails I can connect the usb drive to the Linux machine and recover the data on the mirror.

Now I can sleep at night.

Very good! So you confirm that it also works with a mirror. But keep in mind, that if the internal disk fails, the best method to recover is to remove the internal disk and to put the external disk in its place.

The first step is needed to prevent the problems that the WL-700gE will produce when left alone with a new unused disk. It will leave the disk in an invalid state that urges Linux fdisk to rewrite a clean partitiontable, wiping out the diskname that the NAS had put there, probably in partitiontable 4. Then the NAS won't recognize the disk anymore.
So, its a trick that I found by coincidence.

If you want to be able to see the contents from Windows, point Google to "reiserfs Windows". There are several solutions, maybe one of them works.

Good luck
18-04-2007, 19:39
gimli

Diskname erased

Hi mumsoft,
I have repeated your steps to connect my USB-HDD to the WL700gE but did not succeed. I am pretty sure that I have finished step 1 correctly (4 primary partitions formated as FAT) but in step 3 the fdisk tells me:
'Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel. Building a new DOS disklabel.' I believe that is what you mean by 'missing msdos signatue'. In step 4 I can not create the volume because the discname is 'Foreign Disk 1' and it won't let me create a volume.
My firmware is 1.0.4.6.
Can you please help on this. Thanks!
18-04-2007, 21:57
mumsoft

Quote:

Originally Posted by gimli

Hi mumsoft,
I have repeated your steps to connect my USB-HDD to the WL700gE but did not succeed. I am pretty sure that I have finished step 1 correctly (4 primary partitions formated as FAT) but in step 3 the fdisk tells me:
'Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel. Building a new DOS disklabel.' I believe that is what you mean by 'missing msdos signatue'. In step 4 I can not create the volume because the discname is 'Foreign Disk 1' and it won't let me create a volume.
My firmware is 1.0.4.6.
Can you please help on this. Thanks!

Gimli, I must admit that the same scenario has bitten me once too. I have no real solution other than: try again. Apparently step 1 is the weakest part in my menu. When the Asus erases the disk in step 2, it does something unhealthy, that sometimes wrecks what you have done in step 1, and is needed to get step 3 right.
So, try again, try different FAT-sizes, experiment a bit with step 1, eventually it must succeed.
Good luck, and please report back when you are successful, and how.
It's a bit of a nasty nas, and we all must still learn a lot from it.

Marc
21-01-2008, 12:40
slofs009

HOW-TO make an external disk usable for PC and NAS

I recently bought 2 external 500 GB harddisks to connect via USB with my WL-700G. I read this post about the How-To and must admit I got a bit upset. I don't have a Linux PC and was a bit surprised it would be so complex.
So I started myself to get it working and surprisingly enough, you can do it from the WL-700G menu without any problems.

1. Connect external HD to WL-700G via USB
2. Switch it on
3. Go to Disk Management in the Advanced Setting menu (via Configuration)
4. You will the new foreign disk appear now -> choose Erase. Then it will be available as System disk, instead of Foreign disk
5. Choose Format - it will now be formatted and available to create volumes on
6. Choose Create Volume
7. Create new share (via Share Management)

And voila you have another external disk you can just use as shared network drive (map in your Windows Explorer): \\192.168.1.1\myshare...\ (that is at least my standard gateway ip-adress.
I have added now 2 extra harddisks, so I have now MYVOLUME1 (the 160 GB interal HD), MYVOLUME2 (external harddisk 1, 500GB) and MYVOLUME3 (ext hd 2, 500 GB).
You are also able to use mirroring.

Good luck,

Ralf
21-01-2008, 21:27
mumsoft

Not really the point...

Ralf,

I think being a newbie makes things a little confusing. Now, what you mention here...:

Quote:

Originally Posted by slofs009

I recently bought 2 external 500 GB harddisks to connect via USB with my WL-700G. I read this post about the How-To and must admit I got a bit upset. I don't have a Linux PC and was a bit surprised it would be so complex.
So I started myself to get it working and surprisingly enough, you can do it from the WL-700G menu without any problems.
1. Connect external HD to WL-700G via USB
[cut]
And voila you have another external disk
[cut]
I have added now 2 extra harddisks, so I have now MYVOLUME1 (the 160 GB interal HD), MYVOLUME2 (external harddisk 1, 500GB) and MYVOLUME3 (ext hd 2, 500 GB).
[cut]
Ralf

... is standard Asus functionality.
My HOW-TO though is about something else. I hope you can see what I mean. Just take one of your 2 external disks away from the Asus (not the one you might be using as a mirror, that would cost you too much time re-mirroring), so, take one of these disks, and connect it to your pc. See what happens: I guess, nothing at all. Windows will not recognize it. And even if you had a Linux pc, that would lead to nothing. So, with these disks you can see what's on it, only if you attach them to the Asus white brick.
Now, my How-to is meant to change that. If you follow it, and succeed, you would have disks that are usuable both on your pc AND the Asus brick.

I hope this makes it more clear why I wrote such a complex how-to.

Have fun with yout beauty!
Marc
23-01-2008, 12:37
slofs009

Hi Marc,

Now I understand it !! Thanks a lot, this was certainly not clear to me.
My drives are only used for network purposes, so I do not need to connect them to any PC, hence I do not have the problem you mention.
But in case I do want to do something like this with them I know where to look ... :)

Greetz,

Ralf
23-01-2008, 20:32
mumsoft

Think ahead...

Quote:

Originally Posted by slofs009

Hi Marc,
My drives are only used for network purposes, so I do not need to connect them to any PC, hence I do not have the problem you mention.
Ralf

It's not a problem now, but it may solve a problem in the future. Your external disks are readable by the Asus, right? Now, suppose your Asus turns into a brick one of these days. In fact, you have to bring it back to Asus and you will not see it for several weeks. But you just told your family that you had published the pictures of your Japanese holiday on line. These are on the external disk you still have, but can't access. Happy?

The procedure here first wipes out your disk, and only then makes it available for your Asus and your pc (with Linux somewhere). So, you have to do this in advance, not afterwards.:eek:

Marc
24-04-2008, 13:08
robink

Acces to external disk on Linux WITHOUT losing your Data

See here: http://wl500g.info/showthread.php?t=14128

With the information in that thread you can mount the external disk with Linux, access your data, umount and put it back to the WL700gE without loosing your data. No writing on the disk is needed (except maybe on the file system itself), therefore minimising the risks of loosing something..

If we can make a solution that combines the tricks to get a PC/WL700gE mountable disk from an existing WL700gE External disk without loosing data... maybe... If something else comes to mind I will post it here... But don't count on it, my major concern is getting my external disk from my WL700gE to my Linux system (back is not important)...

Greetings,
Robin