--- wikisrc/ports/xen/howto.mdwn 2018/07/26 11:00:10 1.149 +++ wikisrc/ports/xen/howto.mdwn 2018/07/26 11:08:33 1.150 @@ -19,8 +19,8 @@ Xen supports different styles of guest: [[!table data=""" Style of guest |Supported by NetBSD -PV |Yes -HVM |Yes +PV |Yes (dom0, domU) +HVM |Yes (domU) PVHVM |No PVH |No """]] @@ -35,44 +35,19 @@ There are further features for IOMMU vir AMD's AMD-Vi. TODO: Explain whether Xen on NetBSD makes use of these features. TODO: Review by someone who really understands this. -Generally any machine that runs NetBSD/amd64 will work with Xen and PV -guests. In theory i386 computers (without x86_64/amd64 support) can -be used for Xen <= 4.2, but we have no recent reports of this working -(this is a hint). For HVM guests, hardware support is needed, but it -is common on recent machines. - At boot, the dom0 kernel is loaded as a module with Xen as the kernel. The dom0 can start one or more domUs. (Booting is explained in detail in the dom0 section.) -NetBSD supports Xen in that it can serve as dom0, be used as a domU, -and that Xen kernels and tools are available in pkgsrc. This HOWTO -attempts to address both the case of running a NetBSD dom0 on hardware -and running domUs under it (NetBSD and other), and also running NetBSD -as a domU in a VPS. - -Xen 3.1 in pkgsrc used to support "PCI passthrough", which means that -specific PCI devices can be made available to a specific domU instead -of the dom0. This can be useful to let a domU run X11, or access some -network interface or other peripheral. - -NetBSD 6 and earlier supported Xen 2; support was removed from NetBSD -7. Xen 2 has been removed from pkgsrc. - -Prerequisites -------------- - -Installing NetBSD/Xen is not extremely difficult, but it is more -complex than a normal installation of NetBSD. -In general, this HOWTO is occasionally overly restrictive about how -things must be done, guiding the reader to stay on the established -path when there are no known good reasons to stray. - This HOWTO presumes a basic familiarity with the Xen system architecture, with installing NetBSD on i386/amd64 hardware, and with installing software from pkgsrc. See also the [Xen website](http://www.xenproject.org/). +This HOWTO attempts to address both the case of running a NetBSD dom0 +on hardware and running domUs under it (NetBSD and other), and also +running NetBSD as a domU in a VPS. + Versions of Xen and NetBSD ========================== @@ -82,9 +57,8 @@ which version to choose. Versions not i versions of NetBSD are intentionally ignored. The term "amd64" is used to refer to both the NetBSD port and to the -hardware architecture on which it runs. (Such hardware is made by -both Intel and AMD, and in 2016 a normal PC has this CPU -architecture.) +hardware architecture on which it runs. Such hardware is generally +made by both Intel and AMD, and common on PC computers. Xen versions ------------ @@ -192,24 +166,6 @@ caution that the total situation is comp understood. On top of that caution, the post is about Linux, not NetBSD. TODO: Include link to benchmarks, if someone posts them. -Recommendation --------------- - -Therefore, this HOWTO recommends running xenkernel46, xl, the NetBSD 7 -stable branch, and therefore to use an amd64 kernel as the dom0. -Either the i386PAE or amd64 version of NetBSD may be used as domUs. - -A tentative replacement recommendation is xenkernel48, xl, and NetBSD -8. - -Because bugs are fixed quite often, and because of Xen security -advisories, it is good to stay up to date with NetBSD (tracking a -stable branch), with the Xen kernel (tracking a Xen version via -pkgsrc), and with the Xen tools. Specifically, NetBSD (-7 and --current) got an important fix affecting dom0/domU timesharing in -November, 2015, and xentools46 got a fix to enable Ubuntu guests to -boot in December, 2016. - NetBSD as a dom0 ================