Re: [Xen-users] Disk Partitioning Questions....

Thomas Goirand
Fri, 06 Mar 2009 21:28:10 -0000

Phillip Roberts wrote:
> I am working on starting Virtural Servers at my office and have questions
regarding disk partitioning recommendations.
>
> I am using SLES 10 SP2.....  RAID 5....  280G available...  no external
storage...
>
> 1 - Should the DOM be on primary partition and then place the VM''s
in LVM?

Yes, that would work. However, I found useful to also have most of the
partitions of the dom0 in LVM. I have /var, /tmp, /usr and swap in LVM
as well in all of my dom0.

> 2 - Should I create partitions in the LVM for each of my VM''s
separately or can they all reside on the same partition in the LVM Volume?

Please use the good terminology, this is quite hard to understand what
you want to ask. Here are few definitions:

volume group (VG): the big device that can be an aggregation of multiple
physical partition, that you will slice is logical volumes

logical volume (LV): small partitions that made out of segments (PE) of
a VG.

What yo should do is create at least one LV for each of your VM. What I
often do is one LV for one partition, and one LV for the swap. Then this
makes it like this on my domU startup file:

disk = [
''phy:/dev/mapper/vg0-xen01,sda1,w'',''phy:/dev/mapper/vg0-xen01swap,sda2,w''
]

As a side note, in my example the volume group is called vg0, but it''s
quite useful to use a name that you will NOT find anywhere else in your
servers, otherwise you can have a conflict if you take a HDD from one
server and put it in another server for doing maintenance. This happened
to me, and since then, I always prefix the name of the vg by the
hostname. That makes it something like node2349vg0.

Thomas