NetBSD
so, NetBSD-stable doesn't support PAE or AMD64, and non-PAE Xen systems are hard to come by these days. (understandably... 4GB isn't much these days.) to run on most Xen systems, you need a i386-PAE kernel or a AMD64 (x86_64 in linux nomenclature. Same thing as the AMD64 arch in NetBSD)
NetBSD-current supports both AMD64 (as a Dom0 and DomU) and i386 PAE (DomU only) This will be an overview of how to set that up (specifically on prgmr.com systems, but it should work with any provider that gives you pygrub or pvgrub or the like.)
in the DomU, w/ prgmr.com PyGrub,
title NetBSD install
root (hd0,0)
kernel /boot/netbsd-INSTALL_XEN3_DOMU
title NetBSD run
root (hd0,0)
kernel /boot/netbsd-XEN3_DOMU root=xbd1a
boot the XenU, select the 'NetBSD install' pygrub option
you will need to change the base directory to something like pub/NetBSD/NetBSD-daily/HEAD/200809050002Z
you also might want to change the default mirror
for the Dom0: http://www.netbsd.org/ports/xen/howto.html#netbsd-dom0
install current
(if disk is slow, look into softdep)
untar pkgsrc install pkgsrc/emulators/netbsd32_compat40 install pkgsrc/sysutils/xentools33 and xenkernel33 now pkg_add -f ftp://ftp.netbsd.org/pub/NetBSD/packages/4.0/i386/sysutils/grub-0.97nb8.tgz
