[Test-Announce] Fedora 22 Rawhide 20150203 nightly compose nominated for testing

[Adam Williamson]

On Tue, 2015-02-03 at 18:54 -0600, Dan Mossor wrote:
> On 02/03/2015 06:13 PM, Adam Williamson wrote:
> > On Tue, 2015-02-03 at 18:27 -0500, Joerg Lechner wrote:
> > > Hi,
> > > silly question:
> > > I would like to test now F22-Rawhide i.e. LXDE. My system ist a 
> > > fast laptop with Win 8.1 and Fedora on an external disk. I don't 
> > > want to test in a sandbox.
> > > Is in this stage of development of F22-Rawhide danger that 
> > > Fedora could damage the windows installation? F22-Rawhide will 
> > > be on a seperate spare external disk connected via USB to the 
> > > Windows laptop. Kind Regards
> > 
> > Nothing's 100% guaranteed, but if you don't select the internal 
> > drive as a target disk during installation, it's very unlikely that
> > installing F22 to the external drive will affect your existing 
> > Windows install in any way.
> > 
> However, Fedora has been known to modify UEFI boot settings in such a
> way that the system will not boot at all without that external drive 
> attached. [1]

So, that genre of problem is *there*, but I don't think it's quite as 
you describe it. I'm not sure you're entirely clear on what happened 
in your case.

When you do a UEFI install of Fedora, it deletes any existing UEFI 
boot manager entry named 'Fedora' and creates a new one, pointing to 
the bootloader of the Fedora install you just did. It then makes this 
entry the first one in the UEFI boot manager order.

It doesn't delete any *other* boot entries. Unless your firmware is 
really, really terrible, if the Fedora entry fails, it should fall 
back through the rest of the entries in the BootOrder - in your page, 
it looks like it should then try a UEFI-native boot from 'KingstonDT 
101 G2 PMAP', then BIOS compatibility boot from 'Hard Drive', then 
BIOS compatibility boot from 'CD/DVD Drive'. I don't *think* it's 
correct to say that "What this effectively does is cripple the 
system". The worst effect it can really have is to render previous 
Fedora installations unbootable in certain cases (when the new Fedora 
install's bootloader can't boot the old Fedora install).

Say you have Fedora 21 installed to an internal disk, then you decide 
to try installing Fedora 22 to an external disk; it'll delete the UEFI 
boot manager entry for the Fedora 21 install and create a new one for 
the Fedora 22 install. If you put the Fedora 22 install's EFI system 
partition on the external disk, the 'Fedora' UEFI boot manager entry 
is only going to work when that external disk is plugged in. So you'll 
only be able to boot the Fedora 22 install *or* the Fedora 21 install 
(the Fedora 22 bootloader should have entries for booting the Fedora 
21 install) when the external disk is connected.

A similar case might affect Joerg. I'm not entirely clear from his 
description, though. But say he has Windows 8.1 on the internal disk, 
Fedora 21 (including its ESP) on one external disk, and he wants to 
try installing Rawhide on a *second* external disk. The Fedora 22 
install will delete the UEFI boot manager 'Fedora' entry that points 
to the Fedora 21 external disk and create a new one pointing to the 
Fedora 22 external disk. If the F21 external disk is connected when he 
installs F22, the F22 bootloader may get menu entries to boot the F21 
install, but it'll only work with both disks connected. With only the 
F21 disk connected, he won't be able to boot either Fedora.

I can't see a case where he wouldn't be able to boot Windows, though, 
except for a completely broken firmware which refuses to fall back from 
a UEFI boot manager entry which fails to work. Windows' UEFI boot 
manager entry will not get deleted, and nothing will touch its ESP, 
which is presumably on the internal disk.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Twitter: AdamW_Fedora | XMPP: adamw AT happyassassin . net
http://www.happyassassin.net