Other Fedora Live CD Topics
Following are some random topics that can help you in creating your live CDs with livecd-creator.
Creating Your Own yum Repository
You can use the createrepo command to create your own yum repository. Then you can identify that repository in your kickstart so the RPM software packages it contains can be included on your live CD. Here’s a quick procedure:
# mkdir /var/tmp/newrepo # cp *.rpm /var/tmp/newrepo # createrepo /var/tmp/newrepo
This procedure creates a directory for the new repository (/var/tmp/newrepo) and copies all RPM packages from the current directory to that directory. Running the createrepo command on that directory creates the files needed to use that directory as a yum repository for livecd-creator.
Testing an ISO with qemu
To make sure that your ISO image will boot and work the way you like, you can test it using the qemu command in Fedora. This technique can save you from chewing up a lot of CDs or DVDs as you develop your live CD. You’ll need to install the qemu package (yum install qemu). Here’s an example of a qemu command line for booting a live CD on a Fedora desktop:
# qemu -cdrom F8Desktop.iso
You can improve performance by assigning more memory. For example, adding -m 640 assigns 640MB of memory to the qemu session. If your system supports KVM virtualization, install the kvm package (yum install kvm) and use the qemu-kvm command instead of just qemu to test the ISO.
Burning an ISO to CD or DVD
If the ISO seems to be working with qemu, you can burn it to a CD or DVD. Many choices of open source software tools are available for burning the ISO to CD or DVD. I like k3b for a simple GUI tool for burning CDs and DVDs. To do a quick burn to CD from the command line, you could use cdrecord. For example:
# cdrecord -v F8Desktop.iso
Once the burn is complete, insert the CD into a computer’s CD drive and reboot to test it.
Installing an ISO to USB Flash Drive
If you have a USB flash drive (sometimes called a thumb drive, pen drive, or similar) that has enough space to hold your ISO image, you can copy the files and master boot record information to that USB drive, so that it can behave like a bootable live CD. The livecd-iso-to-disk command does this by overwriting the master boot record on the USB drive, but not overwriting any other files on the drive.
Before trying this procedure, make sure that you know which device represents your USB drive. Because all hard drives in Fedora are now /dev/sd? (instead of /dev/hd? in many cases), you need to be particularly careful to get this designation correct. Also, make sure that your USB flash drive is unmounted. Here’s an example:
# /usr/bin/livecd-iso-to-disk F8Desktop.iso /dev/sdc1
If the USB drive is found not to be bootable, the output will show how to use the parted command to make the drive bootable. As with ISOs on your hard disk, you can boot a live CD from your USB flash drive by using qemu. For example, with the ISO installed on a USB flash drive on /dev/sdc, type the following line to boot it:
# qemu -hda /dev/sdc
If that trick works, assuming that the computer where you want to boot the USB flash drive is capable of booting from a USB drive (most recent computers are), you can simply reboot with the USB flash drive inserted in the computer. It should boot as a regular live CD would.
Using Revisor to Create Live CDs
The Fedora Unity Project has produced a tool called Revisor that offers a graphical way to create live CDs. Since Revisor is available from the Fedora repository, you can install Revisor (yum install revisor) and launch it from the Applications menu on the Fedora desktop (select System Tools > Revisor). For more information on how Revisor works, visit the Fedora Unity site’s Revisor page.