Description of problem:

The Installation Guide is wrong about upgrading from F9 to F11.
In http://docs.fedoraproject.org/install-guide/f11/en-US/html/ch-upgrade-x86.html it says:

Important
It is not possible to upgrade directly from Fedora 9 to Fedora 11. To upgrade Fedora 9 to Fedora 11, upgrade to Fedora 10 first. 

This is simply not true. Upgrading from F9 to F11 using Anaconda or using preupgrade is supported and works (I've checked using preupgrade myself).
It is only required to upgrade to F10 first when using the unsupported live yum upgrade method.


I confirmed this today on #fedora-devel:
<michich> Does anyone know the reason why "It is not possible to upgrade directly from Fedora 9 to Fedora 11."? (source: http://docs.fedoraproject.org/install-guide/f11/en-US/html/ch-upgrade-x86.html) Notice that the guide talks about upgrades using Anaconda, not live yum upgrades where such a requirement is understandable.
<dgilmore> michich: rpm incompatabilities
<dgilmore> michich: F-11 uses stronger hashes than F-9  and the F-9 rpm does not support the new sha256sum hases
<michich> dgilmore, preupgrade F9->F11 worked fine for me. Why?
<dgilmore> michich: anaconda upgrades use the new rpm
<michich> dgilmore, indeed, so it is supposed to work, right?
<geppetto> dgilmore: but that's just a problem for live yum upgrades
<dgilmore> geppetto: right whihc is what i said
<dgilmore> looks like the docs is not quite correct
<dgilmore> geppetto: well what i meant
<michich> dgilmore, that's why I said "Notice that the guide talks about upgrades using Anaconda"
<dgilmore> michich: the guide is wrong
<michich> thanks for confirming my suspicion
<dgilmore> michich: unless im wrong for some reason
<dgilmore> but AFAIK using anaconda based updates from F-9 to F-11 is perfectly supported
<michich> I'll file a BZ against the Install guide
<dgilmore> for yum upgrades you need to at the least install F-10's rpm from the updates repo
<michich> that's exactly how I understand it as well