Thu 19 April 2012

Change in behaviour of livecd-tools: Testing required

Posted by ankur in Tech (457 words, approximately a 2 minute read)

Hi folks,

There has been a change in the way livecd-iso-to-disk works when using a

DVD image. In the past, you had to have one bootable partition on the

USB media you chose to use, and livecd-iso-to-disk would use it to set

up the media. It would copy the required files and the ISO image to this

partition that the user specified.

Due to some changes in anaconda in F17, anaconda can no longer read the

ISO from the same partition. Therefore, upstream has made changes to

livecd-iso-to-disk. It is now necessary to use the --format option while

creating USB media from DVD ISO images. This *formats* the *entire* USB

media (don't use a HDD you use for backups!) and creates two partitions:

"LIVE" and "LIVE-REPO". The ISO image is copied to the "LIVE-REPO"


The earlier command was:

$ livecd-iso-to-disk <path to iso> /dev/sdb1 #(the attachment point of

the *partition*)

The new command is:

$ livecd-iso-to-disk --format --reset-mbr --msdos <path to iso> /dev/sdb #(the

attachment point of the *device*)

I personally feel this is a usability failure, as it restricts the usage

of USB media for installation. One will now have to keep aside a special

USB stick for installations. One cannot use one partition from an

already in-use external HDD. I've filed a bug here[1] as a proposed


In the mean time, livecd-tools needs testing. I've updated the docs on

how to use it[2], but there are areas in there that I'm not well versed

with, such as the part about the media not being bootable, and the use

of "askmethod". I do not know if this method works for boot and netinst

ISO images either since I don't use them regularly. I'm not even sure if

--reset-mbr is necessary.

I'd be grateful if you folks could please test this method of

installation, and file relevant bugs, or update the documentation as


I'd like to stress why it is imperative to test this. Since the

documentation was not up to date, users didn't use the --format option.

This resulted in *no* DVD ISO image being copied at all (It got copied

to / instead, something upstream has fixed now). Therefore, after the

disk partitioning step in anaconda (after it wipes the drives you

select), users were completely caught off-guard when Anaconda popped up

saying, "I need network to continue installation. I can't find any

packages to install on this USB media!". Since the disks had been wiped,

no OS remained, broken system, clear usability #fail. (I was fortunate

enough to have another system to burn a DVD off of, but I personally

know folks who don't have DVD drives in their systems any more, and were

without working systems for a while.)