Tag Archives: storage

Sfdisk: cannot open /dev/sdb read-write

The following command which worked on a Scientific Linux server did not work on a Ubuntu server.

sfdisk -d /dev/sda | sfdisk --force /dev/sdb

Here is the error I received.

sudo sfdisk -d /dev/sdb | sfdisk --force /dev/sdc
         /dev/sdc: Permission denied

	sfdisk: cannot open /dev/sdc read-write

Even with Sudo the command refused to do what I expected. After a quick Google search I found the following which simply suggested to double the Sudo command which if you think about it makes sense.

sudo sfdisk -d /dev/sdb | sudo sfdisk --force /dev/sdc

Now I feel stupid, BTW I was creating a RAID 10 array.

Keeping a VHD Mounted in Windows, Even After A Reboot

While Windows 7 comes with native support for mount VHD files there is one downside , all VHDs are unmount it every the system goes through a reboot. The shortcoming can be remedied with the help of a free third party tool called VHD Attach created by Josip Medved.

You can download VHD attach from the following page http://www.jmedved.com/vhdattach/

This is a two step tutorial. First we’ll have to specify the VHD we need to be auto mounted , second the VHD will be mounted with a drive letter.

Note: This post assumes you already installed the application.

Auto Mount

Start the application and click on the highlighted icon found at the top of the right corner.

VHD Attach

Now click on the Add button.

VHD Attach

Browse to the directory where the VHD you wish to mount is located and double click on the VHD to selected.

VHD Attach

Click on the OK button to save the changes.

VHD Attach

Mount the VHD

Now that you are back in the main menu click on the Open icon.

VHD Attach

Once again browse to the location where VHD is found and double click on it.

VHD Attach

VHD Attach will display relevant information about the VHD. Click on the Attach button found at the top. After this step the VHD becomes accessible from My Computer.

VHD Attach

If you click on the Tools button you can see that the VHD will be mounted on every start up, you can even change the drive letter if you like. You can close the window if you like, from now on the VHD will be automatically mounted every time Windows starts.

VHD Attach

And here is the VHD displayed as a local drive.

VHD Attach

Comments and questions are always welcomed.


VHD Attach Home page jmedved.com/vhdattach/

Windows 7 Network Share Trust

Windows 7 improved various aspects of security over previous version of the Microsoft operating system, while improvements are usually well received some of the new security aspects resulted in Windows no longer trusting my network share despite being in my LAN which is already trusted and not in the Internet where I have no control.

While is not the end of the world, the changes do make it annoying if you have to download multiple files from a network share. This is what I have to put up with every time I have to download a file:

The Solution

Fortunately, the fix is an easy one, and it only requires adding the IP address of the network share as a trusted one.

Start by going to the Control Panel.

And click on Internet Options.

In the Internet Properties window select Local intranet.

Click on Sites.

And in the Advanced button.

Enter the IP address of your NAS or network server and click on Add.

Click on OK.

One last time click on OK.

From now on the network share will not be treated as an untrusted source and you will not be presented with the warning any more. However, if you add another network share with a different IP address you will need to follow the same steps all over again.


3TB Hard Drives Are On The Way

Seagate announced the availability of consumer grade hard drives in the 3TB range. While the increase in density was expected (normal of the storage industry), I can’t help but feel a disturbance in the force. Users and clueless IT technicians are bound to consolidate data that used to be stored in multiple hard drives into a single high capacity 3TB mechanical device that has a history of failure. The problem goes beyond just the manufacturer, temperature, vibration and many other variables decide how reliable a hard drive will be.

Backups Are Not The Norm

The truth is that not everybody keeps backups of their data, when a failure occurs the first thing people do is swear to never buy that brand of drives again.

RAID is not backup, with this in mind it used to be that in order to reach such amounts of storage one would make use of RAID. Now a single 3.5” mechanical device will hold Terabytes of data while spinning at thousands of revolutions per second.

You Have To Upgrade Too

Asides from the human aspects, XP users are out of the equation. On the Windows side users will need to be running either Windows Vista or 7 64bit, updates to the BIOS may be required, and hardware capable of long logical block addressing(LBA).

Otherwise, you can use PAPERBACK v1.00.

My Advice

Don’t be an early tester unless you live on the edge or are used to making backups.


Seagate Confirms 3TB Hard Drive Coming In 2010

Attribution: http://www.flickr.com/photos/scobleizer/