• The OS will boot and run from CD/USB and the configuration will be loaded from/saved to floppy or USB.
• Advantages:
  • Easy to update and maintain.
  • Changes are not saved. If by mistake you delete/modify a system file, just reboot and you get everything like before.
  • Floppies / floppy drives, Flash drives are cheap.
• Disadvantages:
  • Slow to boot if using CD/DVD or USB 1.0.
  • Floppies / floppy drives can be unreliable.
  • The root file system will use space in your RAM.
  • The root file system will be limited to the amount of RAM it uses/gets allocated.
  • Difficult to customize. Changes are not saved.
  • NAS4Free does not officially support floppies (fdformat utility was removed)

• The OS boot loader and a compressed XigmaNAS file system will be installed on HDD/USB/CF.
• The OS will boot from HDD/USB/CF and the compressed file system will be decompressed to RAM, and then run from RAM.
• Advantages:
  • Easy to update and maintain.
  • Damage resistant: Changes are not saved. If by mistake you delete/modify a system file, just reboot and you get everything like before.
• Disadvantages:
  • The root file system will use space in your RAM.
  • The root file system will be limited to the amount of RAM it uses/gets allocated.
  • Difficult to customize. Changes to the OS (deletions/modifications/plug-ins/additions) are not retained.

• The OS is not loaded onto a RAM disk, all reading and writing is done on the hard disk or USB/CF device.
• Advantages:
  • Saves RAM, only necessary files will be loaded on RAM.
  • You can define the size of the root filesystem.
  • Easy to customize.
  • You can install extra packages and / or plug-ins.
• Disadvantages:
  • None of the listed “advantages” is actually a good thing.
  • Difficult to maintain and upgrade.
  • Any changes ( deletions / modifications / plug-ins / additions ) are permanent / final.
  • Easy to break the system if you make a mistake.
  • Must make sure you have a backup of the OS partition before you try to customize.
  • Should be installed onto hard drive because constant reads/writes will shorten the useful life of USB flash / CF cards.

• Read latest upgrade notes before upgrading.
• Advantages:
  • Easy to upgrade. Create new CD or USB and replace old one.
• Disadvantages:
  • You must have physical access to the system.

• Read latest upgrade notes before upgrading.
• Advantages:
  • Easy to upgrade via “System|Firmware” option in WebGUI
  • Physical access to the system not required.
  • Very easy and fast to upgrade and keeping the system updated.
• Disadvantages:
  • Non

• Read latest upgrade notes before upgrading.
• Advantages:
  • None
• Disadvantages:
  • You can upgrade a previous full version only.
  • You must have a cd-rom or extra USB port on the system.
  • You must have physical access to the system.

Reference: Full install vs. Embedded Install? Full install on USB?