On Fri, Jul 24, 
2009 at 03:11:36AM +0800, Teo En Ming wrote:
    
 > Hi All,
    
 >
    
 > I think I may know when my CentOS 4.7 32-bit PV guest can't 
start. It's the
    
 > PAE kernel issue again.
    
 >
    
    
 Xen 3.x supports only PAE domU kernels..
    
    
 so you need to have kernel-xenU installed, which _should_ be PAE
    
 automatically..
    
    
 > After searching through the internet, I came across Pasi's 
article:
    
 >
    
 > Title:[CentOS-virt] Tips for installing Fedora 10 32bit Xen 
PV domU/guest   on
    
 > CentOS 5.3 dom0/host
    
 >
    
 > URL: 
http://lists.centos.org/pipermail/centos-virt/2009-March/000901.html
     >
    
 > Apparently, CentOS 4.7 32-bit anaconda installed the xenU 
(xen-aware)
    
 > kernel. Should I un-install the xenU (xen-aware kernel for
    
 > paravirtualization) and install the PAE kernel for my PV 
guest instead?
    
 >
    
 > <QUOTE Pasi Kärkkäinen>
    
 > Xen only supports PAE kernels for 32bit PV guests.
    
 >
    
    
 Yep. And those PAE kernels need to be Xen-domU-kernels obviously 
:)
      
    
 > </QUOTE>
    
 >
    
 > But then PAE kernels are not xen-aware, so that means I 
cannot run my CentOS
    
 > 4.7 32-bit as PV guest? Instead I got to run CentOS 4.7 
32-bit as HVM guest?
    
 > Fully virtualized guests are slower than paravirtualized 
guests.
    
 >
    
 > Please advise. Thank you!
    
 >
    
    
 You definitely need kernel-xenU, and that should work just fine! 
It should
    
 be PAE automatically.
    
    
 I'm running CentOS4 guests using kernel-xenU, booted with pygrub.
    
    
 -- Pasi