Week 3 - Virtualbox

Different Types of Virtual Hard Disks

In the Hard disk section there are multiple options for the hard disk files these are:

VDI (VirtualBox Disk Image) The VDI format was created by Oracle VM Virtualbox as its own container format for virtual hard disks.
- This format supports both fixed and dynamically allocated storage.
- It also has a high level of redundancy meaning that there is a reduced risk of data loss.
- The downside of this format is that it does not support incremental backups and can be slower than VMDK.
VHD (Virtual Hard Disk) The VHD format was created by microsoft and introduced into windows server 2012.
- Supports both fixed and dynamically allocated storage.
- Has a storage limit of 2TB.
- Supports easy undo and redo of any changes that were made to it
- Supports Multi-user Isolation
VMDK (Virtual Machine Disk) The VMDK format is used by VMware applications.
- Supports both fixed and dynamically allocated storage.
- Supports incremental backups
- Supports snapshots and continuous data protection
- Can recreate and restart a VM from just the vmdk file
HDD (Parallels Hard Disk) The HDD format is used by Parallels. This is mainly used on macOS.
- Virtualbox only supports HDD version 2
QCOW (QEMU Copy-On-Write) This format is undocumented in virtual box but the format is used by QEMU.
- Supports zlib compression
- Supports Multiple VM snapshots
QED (QEMU enhanced disk) This format is undocumented in virtual box but the QED format is an old QEMU disk image format.
- Supports backing up files
- Support for compact image files