[Libguestfs] libguestfs question - multiple partitions in the guest

[Shawn Kennedy]

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).