version 1.134, 2016/12/20 21:22:57
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version 1.135, 2016/12/21 16:57:10
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Line 150 only which command you use, but the comm
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Line 150 only which command you use, but the comm
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xentools packages provide xm for 3.1, 3.3 and 4.1 and xl for 4.2 and up. |
xentools packages provide xm for 3.1, 3.3 and 4.1 and xl for 4.2 and up. |
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In 4.2, you can choose to use xm by simply changing the ctl_command |
In 4.2, you can choose to use xm by simply changing the ctl_command |
variable. |
variable and setting xend=YES in rc.conf. |
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With xl, virtual devices are configured in parallel, which can cause |
With xl, virtual devices are configured in parallel, which can cause |
problems if they are written assuming serial operation (e.g., updating |
problems if they are written assuming serial operation (e.g., updating |
Line 197 work, and an i386 dom0 kernel should in
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Line 197 work, and an i386 dom0 kernel should in
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Xen/dom0 is known to support both i386 and amd64 domUs. |
Xen/dom0 is known to support both i386 and amd64 domUs. |
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i386 dom0 and domU kernels must be PAE (except for an i386 Xen 3.1 |
i386 dom0 and domU kernels must be PAE (except for an i386 Xen 3.1 |
kernel, where one can use non-PAE for dom0 and all domUs); PAE |
kernel, where one can use non-PAE for dom0 and all domUs); PAE kernels |
versions are included in the NetBSD default build. (Note that emacs |
are included in the NetBSD default build. (Note that emacs (at least) |
(at least) fails if run on i386 with PAE when built without, and vice |
fails if run on i386 with PAE when built without, and vice versa, |
versa, presumably due to bugs in the undump code.) |
presumably due to bugs in the undump code.) |
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Because of the above, the standard approach is to use NetBSD/amd64 for |
Because of the above, the standard approach is to use an amd64 Xen |
the dom0 and therefore an amd64 Xen kernel, and to use PAE kernels for |
kernel and NetBSD/amd64 for the dom0. For domUs, NetBSD/i386 (with |
i386 domUs. |
the PAE kernel) and NetBSD/amd64 are in widespread use, and there is |
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little to no Xen-specific reason to prefer one over the other. |
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Note that to use an i386 dom0 with Xen 4.5 or higher, one must build |
Note that to use an i386 dom0 with Xen 4.5 or higher, one must build |
an amd64 Xen kernel and install that on the system. One must also use |
(or obtain from pre-built packages) an amd64 Xen kernel and install |
a PAE i386 kernel. There is no good reason to undertake these |
that on the system. (One must also use a PAE i386 kernel, but this is |
contortions; you should use a NetBSD/amd64 dom0 system. |
also required with an i386 Xen kernel.). Almost no one in the |
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NetBSD/Xen community does this, and the standard, well-tested, |
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approach is to use an amd64 dom0. |
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A [posting on |
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xen-devel](https://lists.xen.org/archives/html/xen-devel/2012-07/msg00085.html) |
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explained that PV system call overhead was higher on amd64, and thus |
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there is some notion that i386 guests are faster. It goes on to |
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caution that the total situation is complex and not entirely |
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understood. On top of that caution, the post is about Linux, not |
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NetBSD. TODO: Include link to benchmarks, if someone posts them. |
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Stability |
Stability |
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Line 247 The following table gives status, with t
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Line 258 The following table gives status, with t
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(generally on the most recent quarterly branch). The first code is |
(generally on the most recent quarterly branch). The first code is |
"builds" if it builds ok, and "FAIL" for a failure to build. The |
"builds" if it builds ok, and "FAIL" for a failure to build. The |
second code/date only appears for xenkernel* and is "works" if it runs |
second code/date only appears for xenkernel* and is "works" if it runs |
ok as a dom0, and "FAIL" if it won't boot or run a domU. |
ok as a dom0 and can support a domU, and "FAIL" if it won't boot or |
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run a domU. |
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xenkernel3 netbsd-6 i386 FAIL 201612 |
xenkernel3 netbsd-6 i386 FAIL 201612 |
xenkernel33 netbsd-6 i386 FAIL 201612 |
xenkernel33 netbsd-6 i386 FAIL 201612 |
Line 303 configuration.
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Line 315 configuration.
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For experimenting with Xen, a machine with as little as 1G of RAM and |
For experimenting with Xen, a machine with as little as 1G of RAM and |
100G of disk can work. For running many domUs in productions, far |
100G of disk can work. For running many domUs in productions, far |
more will be needed. |
more will be needed; e.g. 4-8G and 1T of disk is reasonable for a |
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half-dozen domUs of 512M and 32G each. Basically, the RAM and disk |
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have to be bigger than the sum of the RAM/disk needs of the dom0 and |
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all the domUs. |
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Styles of dom0 operation |
Styles of dom0 operation |
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Line 390 releasedir/i386/binary/kernel/netbsd-XEN
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Line 405 releasedir/i386/binary/kernel/netbsd-XEN
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should not use Xen 3.1.) Both xen and the NetBSD kernel may be (and |
should not use Xen 3.1.) Both xen and the NetBSD kernel may be (and |
typically are) left compressed. |
typically are) left compressed. |
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In a dom0 kernel, kernfs is mandatory for xend to communicate with the |
In a dom0, kernfs is mandatory for xend to communicate with the |
kernel, so ensure that /kern is in fstab. TODO: Say this is default, |
kernel, so ensure that /kern is in fstab. (A standard NetBSD install |
or file a PR and give a reference. |
should already mount /kern.) |
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Because you already installed NetBSD, you have a working boot setup |
Because you already installed NetBSD, you have a working boot setup |
with an MBR bootblock, either bootxx_ffsv1 or bootxx_ffsv2 at the |
with an MBR bootblock, either bootxx_ffsv1 or bootxx_ffsv2 at the |
beginning of your root file system, /boot present, and likely |
beginning of your root file system, have /boot, and likely also |
/boot.cfg. (If not, fix before continuing!) |
/boot.cfg. (If not, fix before continuing!) |
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Add a line to to /boot.cfg to boot Xen. See boot.cfg(5) for an |
Add a line to to /boot.cfg to boot Xen. See boot.cfg(5) for an |
Line 441 Using grub (historic)
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Line 456 Using grub (historic)
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Before NetBSD's native bootloader could support Xen, the use of |
Before NetBSD's native bootloader could support Xen, the use of |
grub was recommended. If necessary, see the |
grub was recommended. If necessary, see the |
[old grub information](/ports/xen/howto-grub/). |
[old grub information](/ports/xen/howto-grub). |
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The [HowTo on Installing into |
The [HowTo on Installing into |
RAID-1](http://mail-index.NetBSD.org/port-xen/2006/03/01/0010.html) |
RAID-1](http://mail-index.NetBSD.org/port-xen/2006/03/01/0010.html) |
explains how to set up booting a dom0 with Xen using grub with |
explains how to set up booting a dom0 with Xen using grub with |
NetBSD's RAIDframe. (This is obsolete with the use of NetBSD's native |
NetBSD's RAIDframe. (This is obsolete with the use of NetBSD's native |
boot.) |
boot. Now, just create a system with RAID-1, and alter /boot.cfg as |
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described above.) |
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Configuring Xen |
Configuring Xen |
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