This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] About defaults

To: Xiaofang Chen <xiachen@xxxxxxxxxxx>
Subject: Re: [Xen-devel] About defaults
From: Steven Hand <Steven.Hand@xxxxxxxxxxxx>
Date: Sun, 11 Apr 2004 03:39:24 +0100
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxxx, Steven.Hand@xxxxxxxxxxxx
Delivery-date: Sun, 11 Apr 2004 03:39:24 +0100
Envelope-to: Steven.Hand@xxxxxxxxxxxx
In-reply-to: Message from Xiaofang Chen <xiachen@xxxxxxxxxxx> of "Sat, 10 Apr 2004 19:10:43 MDT." <Pine.GSO.4.50L0.0404101905350.9367-100000@xxxxxxxxxxxxxxxxx>
>Excuse me, what did you mean by "certainly wrong: you're ... to make real
>physical partition hda1 visible to the domain"?
>Can we use real physical partition in vbd_list?

The vbd_list consists of entries of the form  
     (<real device>, <virt device>, <mode>)

where <real device> is the name of the device (disk, partition, whatever) 
under 'normal' linux, or from the first xenolinux (domain 0), and 
<virt device> is the name you want the new domain (e.g. domain 1) to 
refer to it as, and <mode> is 'w' for read-write or 'r' for read-only. 

Hence the first item in each entry in vbd_list will be a "real physical
partition", but the others will not. No real device should appear more 
than once (since that means you would be trying to let the new domain 
access the same device more than once, which is bad), and no virt device
should appear more than once (since this means you have conflicting ideas
about what that device should be mapped to). 

Furthermore, any [real] device should be accessed either exactly once 
in read-write mode (by all domains), or may be accessed read-only by 
as many domains as you like. 

Hence your setup

> >   vbd_list = [ ('phy:hda1','sda1','w'), ('phy:hda1','sda6','r') ]

is definitely wrong since (a) it attempts to export the same real device
phy:hda1 more than once and (b) it attempts to export a device both 
read-only and read-write. 

>And what the "cmdline_root" should be?

This should be the 'virt device' you have set up to point to a real 
device that has a root file system for that domain on it. 

There's more information in the HOWTOs, FAQs and READMEs.


<Prev in Thread] Current Thread [Next in Thread>