Add & Extend a 2nd Virtual HDD

First of all if you have your FOG server running in a virtual machine these steps will be easy since you will need to create a new (additional) virtual disk and attach it to your virtual machine. This will create two hard drives attached to your FOG server. If you have a physical FOG server you will need to had a second physical hard drive to make this work.

(the rest of this will assume you have FOG running on a virtual machine) With that second hard drive (vmdk) added to your FOG server run the following command

lsblk

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 298.1G  0 disk 
├─sda1   8:1    0 294.3G  0 part /
├─sda2   8:2    0     1K  0 part 
└─sda5   8:5    0   3.8G  0 part [SWAP]
sdb      9:0    0 100.0G  0 disk 

As you can see above there are now 2 hard drives attached to this FOG server. There is /dev/sda that’s about 300G and /dev/sdb that is 100GB in size.

We are going to take that 100GB (new) vmdk file and put a partition and file system on it and then finally mount it on a temp location so we can copy the files in /images to it and off the root file system (which is currently 100% full).

We know that the new disk is /dev/sdb so use fdisk to create a new partition on the blank disk. If you have questions about fdisk google it.

fdisk /dev/sdb
Create a <n>ew
<p>artition
numbere <1>
<default>
<default>
<w>rite the changes to disk
<q>uit fdisk

Next we need to format the new partition with our linux file system.

mkfs.ext4 /dev/sdb1

With the new disk formatted we need to connect it to our really full FOG server. If your fog server is 100% full you may have a problem with the next command you may need to find and delete an unwanted log file from somewhere to make a little room to create a new directory.

For this step we will create a mount point to connect our new hard drive to

mkdir /mnt/test

Now we’ll attach our new disk to that mount point

mount -t ext4 /dev/sdb1 /mnt/test

If you run the lsblk command again you should now see that sdb has a partition sdb1 (note this instruction probably should appear before the we formatted the file system just for the flow of the document).

The command df -h will show both the root file system and the new hard drive mounted on the /mnt/test mount point.

Now we need to move the host image files from the /images directory onto our new empty hard drive.

mv /images/* /mnt/test

After a bit of churning your host image files will be moved to the new disk.

After all of your image files are safely on the new disk we need to un-mount the current mount point and remount the new disk over the /images directory.

We need to unmount the new hard drive from the /mnt/test mount mount point with this command

umount /mnt/test

Run the df -h command to ensure that sdb1 has been unmounted.

Then clean up the test folder (not needed anymore) with

rmdir /mnt/test

Now we need to mount our new hard drive over the /images folder. We can do this with the following command

mount -t ext4 /dev/sdb1 /images

Change to the /images folder and you should see all of your host image files.

At this point we are almost done. If we were to reboot the FOG server this manual mount command would not be active after the reboot. So lets make this change permanent.

You will need to edit the fstab in /etc Insert the following line info fstab at the bottom.

Edit /etc/fstab:

vi /etc/fstab

Instructions on using Vi: Vi

/dev/sdb1    /images    ext4    defaults    0    1

Now lets unmount the images folder with all of the host image files.

umount /images

If you show the files in the /images folder it should be blank.

ls -la /images

Now lets mount the /images folder again using the following command

mount -a

Use the df -h command to show that we’ve mounted /dev/sdb1 on /images.

Reboot your fog server and use the df command to make sure your images are remounted over the /images folder.