Increasing Disk Size Linux Vm

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Adding a new disk to a VMWare Virtual Machine in Linux

Ive been usingVMWarefor a while now and I always get asked some common questions about it. One of those ishow to add a new virtual disk to a Linux virtual machine. So in response to that, here are the steps to adding a new

SCSI based virtual disk to a CentOS Linux virtual machine. The steps for adding a disk to a Windows machine is very

much the same except you would use the Disk Management utility from the Control Panel.

Step 1: Open virtual machine settings

Select your virtual machine, as you can see from the photo I selected the Infrastructure virtual machine. Next press

the Edit virtual machine settings to open the Virtual Machine Settings dialog.

Step 2: Add new hardware

From the Virtual Machine Settings dialog select the Add button at the bottom of the screen. From this dialog
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you can also modify how much memory you dedicate to the machine when it boots.

Step 4: Select new hard disk

From this screen we can see the many types of hardware we can add to a virtual machine. You can emulate just

about any piece of hardware that one can expect in a modern operating system. It definitely makes testing with

different configurations and devices much easier. For our example we want to select Hard Disk and then select the


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Next > button.

Step 5: Create the virtual disk

In the next screen we see the three options for adding a new disk. We can Create a new virtual disk, this will

create a brand new disk on the guest operating system. The second option, Use an existing virtual disk, allows you

to mount a disk from another virtual mach ine. I like to do this with my source drive. I have one virtual disk that

Ive made that has all the Oracle and Linux CDs on it, that way I can just mount it to the machine I need when I

have to do a new install instead of copying the binaries I need across disks, its definitely a big time saver. The last

option is to Use a physical disk, this allows you to mount a local physical disk to the operating system. This option

is akin to NFS mounting a drive to a virtual machine. To add a new disk we select t he Create a new virtual disk


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option and select the Next > button.

Step 6: Select type of disk

Next we want to select the type of disk. Ive been using VMWare for a long time and agree that the recommended

Virtual Disk Type should be SCSI. I dont know why, but Ive had much better success with the SCSI virtual disks


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than the IDE ones. So in this step we want to select SCSI (Recommended) and the Next > button.

Step 7: Set disk size and options

Now we want to set the size of the disk we are creati ng. One of the nice features of VMWare is that you dont have

to allocate all of the disk when you create it. So if you create a 40 GB disk it doesnt have to take it all right away,

the disk will grow as your virtual machine needs it. I will say this is a big performance hit you take when the disk has

to extend, but for most applications its OK. Also, I will warn that if the virtual disk grows and there is no physical disk

left on the host operating system you will see a catastrophic failure and in most cases both the host and guestoperating systems lock up and become unusable. (Dont say I didnt warn you) Lastly, you can split the files into 2GB

sizes, while this isnt necessary, it just makes all the disks much easier to manage and move around. For this step we

want to set our disk size (12 GB in this case), I chose not to allocate the disk space right now (the machine has a


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300 GB drive and has only 20 GB on it) and Split disk into 2 GB files.

Step 8: Name the disk file

This is actually pretty simple in that you decide what you want to physically call the disk and where to put it. .vmdk is

the extension for VMWare virtual disks. After we name the disk we can select the Finish button which adds the disk


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to the virtual machine.

Step 9: Ensure new disk exists

So now we can see that the new disk has been added to the Virtual Machine Settings within the selected virtual

machine. From here the disk acts just like it would if you added a new disk to a standalone server. So we select the


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OK button to continue.

Step 10: Boot the virtual machine

From here we just start the virtual machine like we would normally, either by selecting the button on the toolbar or

selecting the Start this virtual machine link.


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Step 11: Virtual machine start up

The machine boots normally as it would any other time.

Step 12: Create the Partition

After weve logged in and accessed a terminal window as root (or another user with root/sudo privs) we first want to

run fdisk on the newly created drive. In Linux the first SCSI drive is sda, the second sdb, the third sdc, etc. since this

was the second SCSI drive we added to the system, the device is known as /dev/sdb

The first command we want to run is fdisk /dev/sdb (NOTE: Thanks to everyone that caught my typo here)this utility

works very much like the DOS utility of the old days and allows you to create and manage partitions. To create a new

partition we enter the command n to create a new partition. This is going to be a primary partitionp, and the first

partition number 1. Because I want this disk to consume the full 12 GB I specified earlier we start at the first cylinder

and end it at the last cylinder. We then want to write the partition table with the new partition we have just created


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so we enter the command w which writes the new table and exits fdisk.

Step 13: Format the partition

Now that weve create the partition, we now want to format the first with the new file system. Ive decided to use

ext3 filesystem for this disk, ext3 provides all the features of the classic ext2 file system plus journaling which helps

to prevent disk corruption in the event of an improper shutdown and speeds up the recovery process. For a good

overview of Linux standard file systems check out this article:http://linux.org.mt/article/filesystemsSo, to format the

new partition we enter the command mkfs -t ext3 /dev/sdb1. This command makes a new files system with the
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type t ext3 on the /dev/sdb1 partition, this is the first partition on the sdb disk.

Step 14: Create the mount point

Determine where you want to add the new virtual disk youve created. I like to create a partition specifically for all

the software I install after the basic Linux install called/software to do that we run mkdir /software, just a simple

make directory command. Once that is complete we then want to mount the newly created partition. Because we

havent added the partition to the /etc/fstab yet we have to mount it manually. To do that we run mount -t ext3

/dev/sdb1 /software. To break down this command we run mount with the ext3 filesystem type, the partition

/dev/sdb1 to the directory /software. Pretty simple and straight forward. To check that the partition is properly


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mounted we run df -k which shows us the mounted partitions and the amount of available space.

Step 15: Open the fstab file

The fstab file holds all of the used disks and partitions, and determines how they are supposed to be used by theoperating system. So we edit the file to add the newly created partition

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Step 16: Modify the fstab for the new partition

After we open the fstab file in the previous step we add the following line:

/dev/sdb1 /software ext3 defaults 1 1

The first column is the partition name, the second is the default mount point, the third is the filesystem type. The

fourth is the mount options, in this case I used default which mounts the drive rw, suid, dev, exec, auto, nouser and

asynchronous. The 5th and 6th options are for the dump and fsck options. If dump is set to 1 the filesystem is

marked to be backed up, if you are going to have sensitive material on the drive its a good idea to set it to 1. If fsck

is set to greater than 1, then the operating system uses the number to determine in what order fsck should be runduring start up. If it is set to 0 it will be ignored such as in the case of a cdrom drive since its a solid state disk. For

more information on the fstab file check out this article:http://www.tuxfiles.org/linuxhelp/fstab.html
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Lastly, we write and quit the file with the :wq command.

So now that the fstab has been written the drive will be mounted and unmounted when the machine is either started

or shutdown. So there you have it, the quick and dirty process for adding a brand new disk to a virtual machine. Untilnext time

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Increasing Disk Size Linux Vm