Which Platform?

I'm facing a delima.  I want to put Xen on as a production
level server
with individual domains serving the user community.  I can't
figure out
from all the posts, which NetBSD and pkgsrc xen tools
versions would
best serve my intentions.  

Anyone have recommendations on the best (most stable)
platform to use
for dom0?
NetBSD 3.1?  pkgsrc-2006Q2?
NetBSD current?

Can a higher version of NetBSD run as domU than run as dom0?
 Are there
problems mixing and matching pkgsrc versions with the NetBSD
versions?

Thanks for your feedback.

On Fri, 9 Feb 2007, Freidank, Kenneth wrote:
> I'm facing a delima.  I want to put Xen on as a
production level server
> with individual domains serving the user community.  I
can't figure out
> from all the posts, which NetBSD and pkgsrc xen tools
versions would
> best serve my intentions.
>
> Anyone have recommendations on the best (most stable)
platform to use
> for dom0?

Well, we'd say NetBSD 

NetBSD apparently has the edge over Linux for speed of
virtual disk 
access.

> NetBSD 3.1?

That's what I use, but it's Xen2 only. Our Xen3 doesn't
support PCI export 
to DomU, but has other advantages. We don't have things like
xm migrate 
yet.

>  pkgsrc-2006Q2?

pkgsrc-Q4 at least. On dom0 you aren't going to have too
many packages so 
you won't get to play dependency hell if you choose
-current.

> NetBSD current?

Yes if you need Xen3. If it's production, then I'd be
tempted to stick to 
3.1_STABLE (N.B. _STABLE). -current a bit too much of a
moving target for 
me (especially at the moment - hi ad!).

> Can a higher version of NetBSD run as domU than run as
dom0?

Yes, feel free to mix as you see fit.

> Are there problems mixing and matching pkgsrc versions
with the NetBSD 
> versions?

Not really, but make sure you stick to either the release
branch of pkgsrc 
or current (nothing any older). I use -current on dom0 and
the release 
branch of pkgsrc on domU with which I build up a shared vnd
I mount 
read-only across domUs.

-- 
Stephen

On Fri, 9 Feb 2007, Freidank, Kenneth wrote:
> I'm facing a delima.  I want to put Xen on as a
production level server
> with individual domains serving the user community.  I
can't figure out
> from all the posts, which NetBSD and pkgsrc xen tools
versions would
> best serve my intentions.
>
> Anyone have recommendations on the best (most stable)
platform to use
> for dom0?

Well, we'd say NetBSD 

NetBSD apparently has the edge over Linux for speed of
virtual disk 
access.

> NetBSD 3.1?

That's what I use, but it's Xen2 only. Our Xen3 doesn't
support PCI export 
to DomU, but has other advantages. We don't have things like
xm migrate 
yet.

>  pkgsrc-2006Q2?

pkgsrc-Q4 at least. On dom0 you aren't going to have too
many packages so 
you won't get to play dependency hell if you choose
-current.

> NetBSD current?

Yes if you need Xen3. If it's production, then I'd be
tempted to stick to 
3.1_STABLE (N.B. _STABLE). -current a bit too much of a
moving target for 
me (especially at the moment - hi ad!).

> Can a higher version of NetBSD run as domU than run as
dom0?

Yes, feel free to mix as you see fit.

> Are there problems mixing and matching pkgsrc versions
with the NetBSD 
> versions?

Not really, but make sure you stick to either the release
branch of pkgsrc 
or current (nothing any older). I use -current on dom0 and
the release 
branch of pkgsrc on domU with which I build up a shared vnd
I mount 
read-only across domUs.

-- 
Stephen

On Fri, 9 Feb 2007 11:31:38 -0500
"Freidank, Kenneth" <Kenneth.Freidankdelta.com> wrote:

> I'm facing a delima.  I want to put Xen on as a
production level
> server with individual domains serving the user
community.  I can't
> figure out from all the posts, which NetBSD and pkgsrc
xen tools
> versions would best serve my intentions.  
> 
> Anyone have recommendations on the best (most stable)
platform to use
> for dom0?
> NetBSD 3.1?  pkgsrc-2006Q2?
> NetBSD current?

I'd recommend 4.0beta or -current.  -current is usually --
but not
always -- stable, but it's a moving target.
> 
> Can a higher version of NetBSD run as domU than run as
dom0?  Are
> there problems mixing and matching pkgsrc versions with
the NetBSD
> versions?
> 
The issue with mixing pkgsrc versions isn't compatibility,
it's the
ability to compile on one VM and install on the others.


		--Steve Bellovin, http://www.cs.columbi
a.edu/~smb

On Fri, 9 Feb 2007 11:31:38 -0500
"Freidank, Kenneth" <Kenneth.Freidankdelta.com> wrote:

> I'm facing a delima.  I want to put Xen on as a
production level
> server with individual domains serving the user
community.  I can't
> figure out from all the posts, which NetBSD and pkgsrc
xen tools
> versions would best serve my intentions.  
> 
> Anyone have recommendations on the best (most stable)
platform to use
> for dom0?
> NetBSD 3.1?  pkgsrc-2006Q2?
> NetBSD current?

I'd recommend 4.0beta or -current.  -current is usually --
but not
always -- stable, but it's a moving target.
> 
> Can a higher version of NetBSD run as domU than run as
dom0?  Are
> there problems mixing and matching pkgsrc versions with
the NetBSD
> versions?
> 
The issue with mixing pkgsrc versions isn't compatibility,
it's the
ability to compile on one VM and install on the others.


		--Steve Bellovin, http://www.cs.columbi
a.edu/~smb

I broadly concur with Stephen Borrill.

I use Xen 2, because that's all there was when I started and
I haven't
moved to 3 yet.

I would run NetBSD 4.0_BETA2 (really, system built from
netbsd-4) on
the dom0.  I'd be tempted to start with Xen 3.  The reason
for these
choices is to avoid one upgrade.

NetBSD-current isn't stable enough.  Many moments it is just
fine, but
doing a cvs update/rebuild/reinstall has the risk that
you'll need to
expend effort to recover, and this doesn't seem reasonable
for a
production machine.  Release branches generally do not have
problems
with this update practices; I do it all the time on the
netbsd-2 and
netbsd-3 branch and am now starting on netbsd-4.

On the domUs, you can can run any version that supports Xen;
there's
no reason it has to match the dom0.  I use a different
kernel file (in
dom0 root) for each domU, so I can upgrade them separately. 
I have in
fact run different versions, e.g. recent netbsd-4 and
current from a
year ago, and have had no problems.

For pkgsrc, I use the head, and use pkg_rolling-replace to
update.
dom0 won't have much (but it needs python), so this doesn't
hurt
much.  For the domUs, do whatever you'd do if it were a real
machine;
the fact that it's Xen is irrelevant.  That said, the only
two
reasonable choices for pkgsrc are the latest quarterly
branch and the
head.

The head of pkgsrc (and thus all quarterly maintenance
branches) is
intended to work with all currently-maintained versions of
NetBSD, as
well as with other operating systems.  As long as you're
talking
2/3/4/current, the head or the latest quarterly branch
should be fine.


-- 
    Greg Troxel <gdtir.bbn.com>

A stability datapoint: Around January 2006 I installed a
dom0 and a
few domUs, all running NetBSD-current at the time.  Until
there were
power issues in December (failing UPS), the dom0 and domUs
stayed up
and worked fine.  So I think NetBSD is a good choice from
the
reliability viewpoint; netbsd-4 should be even more reliable
since
lots of bugs are fixed since the version I ran.

-- 
    Greg Troxel <gdtir.bbn.com>

I broadly concur with Stephen Borrill.

I use Xen 2, because that's all there was when I started and
I haven't
moved to 3 yet.

I would run NetBSD 4.0_BETA2 (really, system built from
netbsd-4) on
the dom0.  I'd be tempted to start with Xen 3.  The reason
for these
choices is to avoid one upgrade.

NetBSD-current isn't stable enough.  Many moments it is just
fine, but
doing a cvs update/rebuild/reinstall has the risk that
you'll need to
expend effort to recover, and this doesn't seem reasonable
for a
production machine.  Release branches generally do not have
problems
with this update practices; I do it all the time on the
netbsd-2 and
netbsd-3 branch and am now starting on netbsd-4.

On the domUs, you can can run any version that supports Xen;
there's
no reason it has to match the dom0.  I use a different
kernel file (in
dom0 root) for each domU, so I can upgrade them separately. 
I have in
fact run different versions, e.g. recent netbsd-4 and
current from a
year ago, and have had no problems.

For pkgsrc, I use the head, and use pkg_rolling-replace to
update.
dom0 won't have much (but it needs python), so this doesn't
hurt
much.  For the domUs, do whatever you'd do if it were a real
machine;
the fact that it's Xen is irrelevant.  That said, the only
two
reasonable choices for pkgsrc are the latest quarterly
branch and the
head.

The head of pkgsrc (and thus all quarterly maintenance
branches) is
intended to work with all currently-maintained versions of
NetBSD, as
well as with other operating systems.  As long as you're
talking
2/3/4/current, the head or the latest quarterly branch
should be fine.


-- 
    Greg Troxel <gdtir.bbn.com>

A stability datapoint: Around January 2006 I installed a
dom0 and a
few domUs, all running NetBSD-current at the time.  Until
there were
power issues in December (failing UPS), the dom0 and domUs
stayed up
and worked fine.  So I think NetBSD is a good choice from
the
reliability viewpoint; netbsd-4 should be even more reliable
since
lots of bugs are fixed since the version I ran.

-- 
    Greg Troxel <gdtir.bbn.com>

On Fri, Feb 09, 2007 at 02:00:34PM -0500, Greg Troxel
wrote:
> 
> On the domUs, you can can run any version that supports
Xen; there's
> no reason it has to match the dom0.  I use a different
kernel file (in
> dom0 root) for each domU, so I can upgrade them
separately.  I have in
> fact run different versions, e.g. recent netbsd-4 and
current from a
> year ago, and have had no problems.

Just a nitpick, but I've been burned with it a couple
times.
DomU must support the version of the Xen hypervisor you
have.
If you keep your hypervisor constant, it should be a
non-issue.
If you upgrade your hypervisor, you may swear for a bit.
-- 
Chris Dukes
< elfick> willg: you can't use dell to beat people, it
wouldn't stand up
to the strain... much like attacking a tank with a wiffle
bat