Re: xen advice

[Greg Troxel <gdt%ir.bbn.com@localhost>]

  I'm about to replace an oldish i386 (NetBSD 3.1) box with a celeron
  2.8 with a current generation core2duo (8200 I think) and a couple of
  SATA 500GB HDD's that I'll run as s/w RAID1 (raidframe).  It's going

See the message linked from the xen howto describing how to set this up.
The hard part is booting xen from raid1 via grub, but it's quite doable.

Get 4 GB of ram if you can, or at least 2 for sure.

  to be running NetBSD 4.0, the aim being to be a general purpose server
  (apache, zope/plone, sendmail/cyrus/clamav/spamassassin) and hopefully
  I want to retire a development box running CentOS5 and run it in a VM
  of some form.  I'd like to use Xen as I think both NetBSD and CentOS
  will run happily with Xen and I'm pretty sure that VMware doesn't work
  too well as a host OS on NetBSD.

  I'd like to run the NetBSD box as the xen dom-something (what's the

dom0

  right term for the host?) and one or more CentOS 5 installs in DomU's
  (right terminology for the hosted VM's?).

yes, domUs is the right term

  Is that a good configuration and likely to be stable?  If so, what
  kernel will work best on the NetBSD host in terms of the best use of
  the multi-core CPU?

I'm not sure if you can run MP under xen.  Probably you want to start
with xen3, and then you run the XEN3_DOM0 kernel.

The big decision is whether to run i386 or amd64.  Unless you need i386
specifically (e.g., to run binaries like flash) I would be inclined to
run amd64 but I haven't done that myself.  I think you can run a PAE
i386 domU under an amd64 dom0 on current - look at the port-xen archives
for the last month or so.  By staying with all amd64 you should be able
to run 4.0.  I know 4.0 works fine with xen2 and i386 and it's widely
reported ok with xen3 and i386 and I think amd64.

See the xen howto, and join port-xen.