Re: [gentoo-user] Xen vs Citrix XenServer

[Tanstaafl]

Thanks for your response Michael...

On 2012-01-01 11:51 AM, Michael Mol <mikemol@×××××.com> wrote:
> On Sun, Jan 1, 2012 at 11:18 AM, Tanstaafl wrote:
> While I haven't played with XenServer, I have played with its
> open-source clone, XCP, and was very annoyed by it. I'd rather run a
> Gentoo dom0.

I just thought that running a bare metal hyperviser would be more 
stable/reliable, and running it on a thumb drive would be much more 
convenient.

>> First - I want to use a bare metal hypervisor that supports the
>> following:
>>
>> 1. Can be installed on a USB FLASH drive (I have some Dell
>> Poweredge 2970 servers with the internal USB slot for just this
>> purpose), and

> I don't think I've heard of anyone doing this, but I don't see why
> it'd be a problem.

Definitely not a problem for XenServer (although v6 isn't officially 
supported on a thumb drive yet), so I was mainly wondering about Xen 
itself...

>> 2. Fully supports both Windows Server 2008 (our Domain Controller),
>> and Gentoo Linux (our mail and web servers).

> The xen supports hvm, where it emulates hardware; in a full hvm VM,
> *any* operating system comfortable on x86 should run.
>
> There's also paravirtualization, which is faster, and is likely what
> you're thinking of wrt 'bare metal'. Signed drivers for paravirt
> mode for hardware (such as your network, disk or system clock) are
> available for current versions of Windows.

Yes, PV is what I was thinking of, thanks - and apparently this wouldn't 
be a problem with gentoo either?

>> I can't seem to find an ebuild for the xenserver tools, and when
>> looking found out about Xen (I had thought that it went away a long
>> time ago)...

> * app-emulation/xen-tools
>       Available versions:  3.4.2-r3 ~3.4.2-r5 ~4.1.1-r5 4.1.1-r6
> ~4.1.2-r2!t {acm api custom-cflags debug doc flask hvm pygrub qemu
> screen xend}
>       Homepage:            http://xen.org/
>       Description:         Xend daemon and tools

Hmm... so will these tools work with XenServer? Or are they just for Xen?

Also, I ran across an article on the gentoo wiki that said that the VM 
images for Xen and XenServer are NOT compatible, which I find odd if 
XenServer is just Xen with some additional tools provided by Citrix.

The article also said that the single biggest advantage of XenServer is 
the amount of time required to get something up and running - minutes 
for XenServer, compared to days for Xen - is this dated info, or still true?

> * sec-policy/selinux-xen
>       Available versions:  [M]2.20110726
>       Homepage:            http://www.gentoo.org/proj/en/hardened/selinux/
>       Description:         SELinux policy for xen
>
> * sys-kernel/xen-sources
>       Available versions:
>          (2.6.18-r12)    2.6.18-r12!b!s
>          (2.6.34-r3)     ~2.6.34-r3!b!s
>          (2.6.34-r4)     ~2.6.34-r4!b!s
>          (2.6.38)        ~2.6.38!b!s
>          {build deblob symlink}
>       Homepage:            http://xen.org/
>       Description:         Full sources for a dom0/domU Linux kernel to
> run under Xen

I though that xen-sources were no longer needed as of kernel 2.6.33+?

Thanks again Michael,

Charles