boot.iso vs netinst.iso vs efiboot.img

[Chris Murphy]

On Jan 26, 2013, at 10:30 AM, John Reiser <jreiser at bitwagon.com> wrote:

>> dd is recommended dead last, really? 
> 
> Under some conditions, livecd-iso-to-disk can be a lot faster because it uses rsync
> to update an existing Packages directory.  So if you have a USB stick of full install
> for RC1, then running livecd-iso-to-disk using RC2.iso will transfer only updated
> files below Packages [plus other files not below Packages].

That's interesting, I didn't know that. But it's inapplicable for non-testers, I think.

> Using 'dd' requires a USB stick that is "dedicated" to that single use,
> while the results of livecd-iso-to-disk can co-exist with other files
> on the USB stick.  In the case of LiveCD spins, this is essential
> in order to make a system with persistent user data.

Yeah OK but the first media recommended is still DVD/CD which also doesn't allow for persistent user data. The modern equivalent is to dd to a USB stick. In fact I think this idea of burning actual media is immensely wasteful and archaic and shouldn't be the first recommended media anymore. Increasingly laptops aren't coming with optical drives at all.

> 
> I have not had problems using livecd-iso-to-disk with full install .iso files.

I'm not having problem either, except that if you follow the documentation, you don't get UEFI or UEFI Secure Boot capable USB media. You don't get persistent user data. You don't get a reformat if you've used the USB stick for something else, and you end up with obscure problems you didn't know a reformat would fix. So…


> The only hassles are when I switch between i386 and x86_64, or between
> UEFI and non-UEFI systems, both of which work better for me with a re-format.

OK and that would be the case in any event. So I'm still left wondering why dd is last. Since burning to actual DVD media is first, and that's a given it completely takes over that media, I think a destructive, takes the media over, does not create  persistent user data, using dd to a USB stick makes infinitely more sense as a primary recommendation. Unless there's some known problem or flakiness with a large body of hardware that I'm not aware of.

So far for me, dd'd USB sticks have booted BIOS, UEFI, Mac EFI, and UEFI Secure Boot hardware. With a single command. And if you use a bs=128k it goes WAY faster than the default block size of 512 bytes. As in 20MB/s compared to 1MB/s.

Anyway I'm still left wondering why dd is dead last. But even more so why DVD burning is first, and of the USB creation methods that LiveCD Creator is first. I stopped testing that with F15 because it wouldn't make Mac EFI bootable USB sticks, can it make UEFI boot media at all? IF not, it should be demoted to dead last.


Chris Murphy