Libguestfs - Aug 2012 - libguestfs question - multiple partitions in the guest

On Wed, Aug 01, 2012 at 11:47:14AM -0500, Shawn Kennedy
wrote:
> Problem:
> When trying to inspect the guest using a command like 'virt-ls', we
> get back:
> 
> ~]# virt-ls -d guest /path
> virt-ls: multi-boot operating systems are not supported by the -i option
What does virt-inspector2 [this is RHEL 6] display for this guest?

  virt-inspector2 -d guest

virt-ls fundamentally doesn't work with multi-boot guests.  However
that doesn't mean to say you can't use libguestfs, you just need to
use some lower level tools or write a Perl/Python/whatever script
against the API.  Have a look at the second example in the
guestfs-perl(3) / guestfs-python(3) man pages to give you some ideas
how to go about this.

By the way it's probably better to use the RHEL 6.3 package,
libguestfs 1.16.19, since it has more bugs fixed.
> Question:
> We know it's because we have 2 filesystems in the guest and
> we have no problem using the '-m' option on the lower-level tools,
> but how do we know which filesystem is mounted??  A simple
> 'mount' command could tell us that, but how to run it if I
> don't know which -m mount point to use??
If I understand your question correctly, then the 'mountpoints'
command lists what is mounted, eg:

  $ guestfish -c qemu:///system -d F16x64 -i --ro
  
  Welcome to guestfish, the libguestfs filesystem interactive shell for
  editing virtual machine filesystems.
  
  Type: 'help' for help on commands
        'man' to read the manual
        'quit' to quit the shell
  
  Operating system: Fedora release 16 (Verne)
  /dev/mapper/vg_f16x64-lv_root mounted on /
  /dev/vda2 mounted on /boot
  
  ><fs> mountpoints 
  /dev/vg_f16x64/lv_root: /
  /dev/vda2: /boot

(or 'mounts' which does the same but only lists the devices).

Please send replies to the mailing list.  I hopefully deleted any
specifics of your environment in this reply.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into Xen guests.
http://et.redhat.com/~rjones/virt-p2v

Hi Richard,

Because I have 2 filesystems (one in a mounted LV and one in a unmounted
LV), I get 2 sets of mountpoints in virt-inspector2 ....

    <mountpoints>
      <mountpoint
dev="/dev/VG1/LV0001.root">/</mountpoint>
      <mountpoint
dev="/dev/VG1/LV0001.var">/var</mountpoint>
      <mountpoint
dev="/dev/VG1/LV0001.app1">/app1</mountpoint>
      <mountpoint dev="/dev/sda1">/boot</mountpoint>
      <mountpoint dev="/dev/VG1/home">/home</mountpoint>
      <mountpoint dev="/dev/VG1/logs">/logs</mountpoint>
      <mountpoint dev="/dev/VG1/cores">/cores</mountpoint>
      <mountpoint
dev="/dev/VG1/storage">/storage</mountpoint>
    </mountpoints>

    <mountpoints>
      <mountpoint
dev="/dev/VG1/LV0002.root">/</mountpoint>
      <mountpoint
dev="/dev/VG1/LV0002.var">/var</mountpoint>
      <mountpoint
dev="/dev/VG1/LV0002.app1">/app1</mountpoint>
      <mountpoint dev="/dev/sda1">/boot</mountpoint>
      <mountpoint dev="/dev/VG1/home">/home</mountpoint>
      <mountpoint dev="/dev/VG1/logs">/logs</mountpoint>
      <mountpoint dev="/dev/VG1/cores">/cores</mountpoint>
      <mountpoint
dev="/dev/VG1/storage">/storage</mountpoint>
    </mountpoints>

So, which one is the real one??  If I log into the guest directly,
I know the /dev/VG1/LV0002* is the mounted partition (by
using 'mount' command or by examining /etc/fstab). 

(from the guest)
# mount | grep root
/dev/mapper/VG1-LV0002.root on / type ext3 (rw)

As much as I would like to, we cannot move the RHEL release to
the next release.  Project restrictions and all ... :-) 

Lastly, where is 'guestfish' installed on the system?? It's not
installed
 on my system, even though I have installed the RHEL6.2 RPMs. 

# rpm -qa | grep libguest
python-libguestfs-1.7.17-26.el6.x86_64
libguestfs-1.7.17-26.el6.x86_64
libguestfs-tools-c-1.7.17-26.el6.x86_64
libguestfs-mount-1.7.17-26.el6.x86_64
libguestfs-tools-1.7.17-26.el6.x86_64

# guestfish
-bash: guestfish: command not found
> -----Original Message-----
> From: Richard W.M. Jones [mailto:rjones at redhat.com] 
> On Wed, Aug 01, 2012 at 11:47:14AM -0500, Shawn Kennedy wrote:
> > Problem:
> > When trying to inspect the guest using a command like
'virt-ls', we
> > get back:
> >
> > ~]# virt-ls -d guest /path
> > virt-ls: multi-boot operating systems are not supported by the -i
option
> 
> What does virt-inspector2 [this is RHEL 6] display for this guest?
> 
>   virt-inspector2 -d guest
> 
> virt-ls fundamentally doesn't work with multi-boot guests.  However
> that doesn't mean to say you can't use libguestfs, you just need to
> use some lower level tools or write a Perl/Python/whatever script
> against the API.  Have a look at the second example in the
> guestfs-perl(3) / guestfs-python(3) man pages to give you some ideas
> how to go about this.
> 
> By the way it's probably better to use the RHEL 6.3 package,
> libguestfs 1.16.19, since it has more bugs fixed.
> 
> > Question:
> > We know it's because we have 2 filesystems in the guest and
> > we have no problem using the '-m' option on the lower-level
tools,
> > but how do we know which filesystem is mounted??  A simple
> > 'mount' command could tell us that, but how to run it if I
> > don't know which -m mount point to use??
> 
> If I understand your question correctly, then the 'mountpoints'
> command lists what is mounted, eg:
> 
>   $ guestfish -c qemu:///system -d F16x64 -i --ro
> 
>   Welcome to guestfish, the libguestfs filesystem interactive shell for
>   editing virtual machine filesystems.
> 
>   Type: 'help' for help on commands
>         'man' to read the manual
>         'quit' to quit the shell
> 
>   Operating system: Fedora release 16 (Verne)
>   /dev/mapper/vg_f16x64-lv_root mounted on /
>   /dev/vda2 mounted on /boot
> 
>   ><fs> mountpoints
>   /dev/vg_f16x64/lv_root: /
>   /dev/vda2: /boot
> 
> (or 'mounts' which does the same but only lists the devices).