My Notes on Information Technology | Shamly

In the earlier post (click here to read the post) I talked about adding a virtual disk to a Windows virtual machine. This post is going to focus on adding a virtual disk to a Linux virtual machine.

The initial steps that you need to follow in adding a virtual disk to the Linux machine is the same as for the windows machine. What differs is how the new disk is mounted and used in each OS. So you need to follow all the steps in my previous post right up to the point where you boot the guest operating system.

From here things are a bit different. Below are the steps you will need to follow to get the new virtual disk up and running

• Once the guest operating system has booted up, login as root or any user that has sudo privileges. Remember that in Linux the first SCSI drive is sda, the second sdb etc… Let’s assume that this was the second SCSI drive we added to the system, so the device will be  known (available for use) as /dev/sdb

• Once that is sorted out, we need to use the fdisk utility to initialize the virtual disk as a partition. The command is fdisk /dev/sdb

• Enter the command n to create a new partition and enter 1 for first cylinder to mention that we will be using the whole disk

• Once this is done we need to write a new partition table to this newly created partition. For that enter w which writes the new table and exits fdisk.

• Now that we have created the partition, we need to format it. I am going to use the ext3 file system for this new disk. Therefore the command to format the new partition is mkfs -t ext3 /dev/sdb1.

• Now let’s mount the partition. I am going to name this partition usr2. So first of all I go to the root directory (cd /) and use the command mkdir usr2. mkdir will create a folder by the name of usr2 and we are going to mount the partition on to this directory.

• To mount the partition we run the command mount -t ext3 /dev/sdb1 /software. If you need to verify that the partition has been mounted, run the command df –h.

• Now this mount will work until the virtual OS is restarted and we will have to manually mount it again.  So to make sure that the partition mounts every time the machine reboots, we need to add an entry in /etc/fstab.

• So open the fstab file using the vi editor and add a new line as follows,
  • /dev/sdb1 /software ext3 defaults 1 1
  • To understand how the /etc/fstab file under Linux works, and how to edit it yourself check out this article: http://www.tuxfiles.org/linuxhelp/fstab.html

• So once the fstab has been written, the partition (drive) will be mounted and un-mounted whenever the machine is started or shutdown.