version 1.203, 2021/03/15 00:11:52
|
version 1.204, 2021/03/15 00:25:54
|
Line 27 PR.
|
Line 27 PR.
|
|
|
The basic concept of Xen is that the hypervisor (xenkernel) runs on |
The basic concept of Xen is that the hypervisor (xenkernel) runs on |
the hardware, and runs a privileged domain ("dom0") that can access |
the hardware, and runs a privileged domain ("dom0") that can access |
disks/networking/etc. One then runs additonal unprivileged domains |
disks/networking/etc. One then runs additional unprivileged domains |
(each a "domU"), presumably to do something useful. |
(each a "domU"), presumably to do something useful. |
|
|
This HOWTO addresses how to run a NetBSD dom0 (and hence also build |
This HOWTO addresses how to run a NetBSD dom0 (and hence also build |
Line 45 Xen supports different styles of guests.
|
Line 45 Xen supports different styles of guests.
|
[[!table data=""" |
[[!table data=""" |
Style of guest |description |NetBSD dom0? |NetBSD domU? |
Style of guest |description |NetBSD dom0? |NetBSD domU? |
PV |Paravirtualization (hypercalls) |yes |yes |
PV |Paravirtualization (hypercalls) |yes |yes |
HVM |unmodified guest - domU perceives HW |N/A |yes |
HVM |unmodified guest - domU perceives HW |can run guests |yes |
PVHVM |Like HVM but also PV drivers |N/A |current only |
PVHVM |Like HVM but also PV drivers |can run guests |current only |
PVH | |not yet |current only |
PVH |Lightweight HVM (no qemu) and PV |not yet |current only |
"""]] |
"""]] |
|
|
In Para-Virtualized (PV) mode, the guest OS does not attempt to access |
In Para-Virtualized (PV) mode, the guest OS does not attempt to access |
Line 85 There is a concept of Xen running on ARM
|
Line 85 There is a concept of Xen running on ARM
|
|
|
The dom0 system should be amd64. (Instructions for i386PAE dom0 have been removed from the HOWTO.) |
The dom0 system should be amd64. (Instructions for i386PAE dom0 have been removed from the HOWTO.) |
|
|
The domU can be i386PAE or amd64. |
The domU can be i386 PAE or amd64. |
i386PAE at one point was considered as [faster](https://lists.xen.org/archives/html/xen-devel/2012-07/msg00085.html) than amd64. |
i386 PAE at one point was considered as [faster](https://lists.xen.org/archives/html/xen-devel/2012-07/msg00085.html) than amd64. |
|
However, as of 2021 it is normal to use amd64 as the domU architecture, and use of i386 is dwindling. |
|
|
## Xen Versions |
## Xen Versions |
|
|
Line 105 Xen Version |Package Name |Xen CPU Suppo
|
Line 106 Xen Version |Package Name |Xen CPU Suppo
|
|
|
See also the [Xen Security Advisory page](http://xenbits.xen.org/xsa/). |
See also the [Xen Security Advisory page](http://xenbits.xen.org/xsa/). |
|
|
Older Xen had a python-based management tool called xm, now replaced |
Older Xen had a python-based management tool called xm; this has been |
by xl. |
replaced by xl. |
|
|
## NetBSD versions |
## NetBSD versions |
|
|
Xen has been supported in NetBSD for a long time, at least since 2005. |
Xen has been supported in NetBSD for a long time, at least since 2005. |
Initially Xen was PV only. |
Initially Xen was PV only. |
|
|
NetBSD has supported PV for a very long time, in both dom0 and domU. |
NetBSD Xen has always supported PV, in both dom0 and domU; for a long |
NetBSD >=8 supports HVM mode as a domU (HVM as a dom0 does not make |
time this was the only way. NetBSD >=8 as a dom0 supports HVM mode in |
sense). |
domUs (HVM as a dom0 does not make sense). |
|
|
Support for PVHVM and PVH is available only in NetBSD-current; this is |
Support for PVHVM and PVH is available only in NetBSD-current; this is |
currently somewhat experimental, although PVHVM appears reasonably |
currently somewhat experimental, although PVHVM appears reasonably |