Booting Linux off USB pendrives

Booting a Linux system off USB Pendrives is one of my favorite things.

On a laptop we have the following advantages,

• The Harddisk can be shutdown and that reduces power consumption (hdparm)


• The system heats lesser and the fans are triggered less frequently


• The system can take more shocks (a bumpy backseat taxi ride)

With old workstation hardware,

• Can be used for quick testing of the hardware platforms


• Linux (Ubuntu these days) works quite well with most hardware


• One Downside: Many old motherboard BIOS do not support a USB boot

I have preferred a USB "boot-stick" to a LiveCD in most cases.

Questions.

1. What other advantages and problems have you seen or anticipate with USB booted Linux?
   
   
   
   • What is your choice of Linux for this purpose?
   
   
   • Would you suggest ext4 or something more proven/stable for a linux usb-boot?
   
   
   • Do you often find USB drives getting corrupted?
   
   
   • Do you partition your USB drives?
   
   

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Recent install guide reference,
Ubuntu Karmic Koala Encrypted Flash Memory Installation (edited July 22 2009).

This install guide is for installing Ubuntu 'Karmic Koala' in a USB flash memory stick with
the LUKS encrypted ext4 file system by running the Ubuntu Karmic Koala 'Alternate CD'.

Answer

When booting of USB media, I would be careful of the following:

1. Swap, unless you need it, save the writes of the flash


2. Keep the filesystem slim, turn off SELinux/AppArmour unless you need it


3. Tune the journaling and cache settings to get better performance

I have a USB key that I use to boot all my systems, it contains the kernel and bootloader with configurations for machine. I also keep the encryption keys for my hard-disks on it.