[SLL] To Xen or not to Xen

[Jarod Wilson]

On Wednesday 12 September 2007 10:01:46 am Howard Gibson wrote:
> On Mon, 10 Sep 2007 14:13:43 -0700
>
> Bill Thompson <Billt at Mahagonny.com> wrote:
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> >
> > Hey Gang,
> >
> > I haven't received much from the list since the server change, so
> > instead of an ubiquitous "test message" how about a word of advice.
> >
> > I'm toying with he idea of adding a web & DNS server to my existing
> > Linux firewall. Would you:
> >
> > A) Use SElinux to secure the server processes, running the firewall
> > and servers in the same machine.
> >
> > B) Use XEN to run a separate virtual machine for the services...
>
> Bill,
>
>    Xen disables your serial port and floppy drives.  My desktops at home
> now are Xen free.  The experience was very frustrating.

Can't comment on the floppy drive, I never use the things anymore, but Xen 
doesn't exactly disable your serial ports, it just hijacks them. To be more 
specific, the hypervisor takes direct control of serial ports, and provides 
pseudo-serial ports for the kernel to use, which are supposed to be 
redirected through the hypervisor layer. Sometimes things go haywire with 
that setup (the pseudo-serial ports don't respond correctly to all IOCTLS), 
but I've got working serial ports on multiple xen boxes -- that's where the 
console output on most of them goes.


-- 
Jarod Wilson
jarod at wilsonet.com