guestfs-testing - Man Page

Run:

 libguestfs-test-tool

This command does a very simple, non-destructive test that basic libguestfs is functioning.  You don't need to run it as root.

If it doesn't print ===== TEST FINISHED OK =====, report it as a bug.  It is very important that you include the complete, unedited output of libguestfs-test-tool in your bug report.  See the "Bugs" section at the end of this page.

If your host has hardware virt acceleration, then with a hot cache libguestfs should be able to start up in a few seconds.  Run the following command a few times:

 time guestfish -a /dev/null run

After a few runs, the time should settle down to a few seconds (under 3 seconds on fast 64 bit hardware).

If the command above does not work at all, use libguestfs-test-tool(1).

Look at the output of libguestfs-test-tool and check:

• Which version of libguestfs is being used?  Near the beginning of the output you'll see a line like:

   library version: 1.22.0fedora=19,release=1.fc19,libvirt

• Is libvirt being used?  You can tell the difference by looking for the backend:

   guestfs_get_backend: direct

  or:

   guestfs_get_backend: libvirt

• Which version of qemu is being used?  It may be printed out:

   libguestfs: qemu version 1.5

• Which kernel is being used?  supermin(1) will try to pick the latest kernel installed on your machine.  You can see the version in the appliance output, eg:

   [    0.000000] Linux version 3.9.2-200.fc18.x86_64 [...]

You can use any guest disk image for this test.  Make sure you use the --ro flag so that guestfish(1) will open the disk image read-only.

 guestfish --ro -a /path/to/disk.img -i

If the command is successful, it should print out the guest operating system name and put you at the guestfish ><fs> prompt. You can use guestfish commands like ll / to look inside the disk image.  To exit, type exit.

If you get an error, try enabling debugging (add -v to the command line).  Also make sure that libguestfs-test-tool(1) succeeds.

You may also have to disable libvirt by setting this:

 export LIBGUESTFS_BACKEND=direct

If you have a disk image available over HTTP/FTP, try to open it.

 guestfish --ro -i --format=raw -a http://www.example.com/disk.img

For SSH you will need to make sure that ssh-agent is set up so you don't need a password to log in to the remote machine.  Then a command similar to this should work:

 guestfish --ro -i --format=raw \
   -a ssh://remote.example.com/path/to/disk.img

If you get an error, try enabling debugging (add -v to the command line).  Also make sure that libguestfs-test-tool(1) succeeds.

Run virt-alignment-scan(1) on guests or disk images:

 virt-alignment-scan -a /path/to/disk.img

or:

 virt-alignment-scan -d Guest

Does the alignment report match how the guest partitions are aligned?

virt-cat(1) can display files from guests.  For a Linux guest, try:

 virt-cat LinuxGuest /etc/passwd

A recent feature is support for Windows paths, for example:

 virt-cat WindowsGuest 'c:\windows\win.ini'

An even better test is if you have a Windows guest with multiple drives.  Do D:, E: etc paths work correctly?

virt-copy-in(1) can recursively copy files and directories into a guest or disk image.

 virt-copy-in -d Guest /etc /tmp

This should copy local directory /etc to /tmp/etc in the guest (recursively).  If you boot the guest, can you see all of the copied files and directories?

Shut the guest down and try copying multiple files and directories:

 virt-copy-in -d Guest /home /etc/issue /tmp

virt-copy-out(1) can recursively copy files and directories out of a guest or disk image.

 virt-copy-out -d Guest /home .

Note the final space and period in the command is not a typo.

This should copy /home from the guest into the current directory.

virt-df(1) lists disk space.  Run:

 virt-df

You can try comparing this to the results from df(1) inside the guest, but there are some provisos:

• The guest must be idle.
• The guest disks must be synched using sync(1).
• Any action such as booting the guest will write log files causing the numbers to change.

We don’t guarantee that the numbers will be identical even under these circumstances.  They should be similar.  It would indicate a bug if you saw greatly differing numbers.

Run:

 virt-df --csv > /tmp/report.csv

Now try to load this into your favorite spreadsheet or database.  Are the results reproduced faithfully in the spreadsheet/database?

http://www.postgresql.org/docs/8.1/static/sql-copy.html http://dev.mysql.com/doc/refman/5.1/en/load-data.html

virt-edit(1) can edit files in guests.  Try this command on a RHEL or Fedora guest:

 virt-edit LinuxGuest /etc/sysconfig/network

On other Linux guests try editing other files such as:

 virt-edit LinuxGuest /etc/motd

Are the changes seen inside the guest when it is booted?

virt-filesystems(1) can be used to display filesystems in a guest.  Try this command on any disk image or guest:

 virt-filesystems -a /path/to/disk.img --all --long -h

or:

 virt-filesystems -d Guest --all --long -h

Do the results match what is seen in the guest?

Use virt-inspector(1) to get a report on all of your guests or disk images:

 virt-inspector -a /path/to/disk.img | less

or:

 virt-inspector -d Guest | less

Do the results match what is actually in the guest?

If you have an unusual guest (a rare Linux distro, a very new version of Windows), does virt-inspector recognize it?  If not, then it's probably a bug.

List all setuid or setgid programs in a Linux virtual machine:

 virt-ls -lR -d Guest / | grep '^- [42]'

List all public-writable directories in a Linux virtual machine:

 virt-ls -lR -d Guest / | grep '^d ...7'

List all Unix domain sockets in a Linux virtual machine:

 virt-ls -lR -d Guest / | grep '^s'

List all regular files with filenames ending in ‘.png’:

 virt-ls -lR -d Guest / | grep -i '^-.*\.png$'

Display files larger than 10MB in home directories:

 virt-ls -lR -d Guest /home | awk '$3 > 10*1024*1024'

Find everything modified in the last 7 days:

 virt-ls -lR -d Guest --time-days / | awk '$6 <= 7'

Find regular files modified in the last 24 hours:

 virt-ls -lR -d Guest --time-days / | grep '^-' | awk '$6 < 1'

Do the results match what is in the guest?

Use virt-make-fs(1) to create a disk image from any tarball that you happen to have:

 virt-make-fs --partition=mbr --type=vfat /any/tarball.tar.gz output.img

Add ‘output.img’ as a raw disk to an existing guest.  Check the guest can see the files.  This test is particularly useful if you try it with a Windows guest.

Try other partitioning schemes, eg. --partition=gpt.

Try other filesystem formats, eg. --type=ntfs, --type=ext2.

Use virt-rescue(1) to examine, rescue or repair a shut off guest or disk image:

 virt-rescue -a /path/to/disk.img

or:

 virt-rescue -d Guest

Can you use ordinary shell commands to examine the guest?

Use virt-resize(1) to give a guest some more disk space.  For example, if you have a disk image that is smaller than 30G, increase it to 30G by doing:

 truncate -s 30G newdisk.img
 virt-filesystems -a /path/to/olddisk.img --all --long -h
 virt-resize /path/to/olddisk.img newdisk.img --expand /dev/sda1
 qemu-kvm -m 1024 -hda newdisk.img

Does the guest still boot?  Try expanding other partitions.

Using virt-sparsify(1), make a disk image more sparse:

 virt-sparsify /path/to/olddisk.img newdisk.img

Is newdisk.img still bootable after sparsifying?  Is the resulting disk image smaller (use du to check)?

Using virt-builder(1), choose a guest from the list:

 virt-builder -l

build it:

 virt-builder -o disk.img [os-version from list above]

and boot it:

 qemu-kvm -cpu host -m 2048 -drive file=disk.img,format=raw

Does it boot?

Note that this really will mess up an existing guest, so it's better to clone the guest before trying this.

 virt-sysprep --hostname newhost.example.com -a /path/to/disk.img

Was the sysprep successful?  After booting, what changes were made and were they successful?

Use virt-win-reg(1) to dump out the Windows Registry from any Windows guests that you have.

 virt-win-reg --unsafe-printable-strings WindowsGuest 'HKLM\Software' |
   less

 virt-win-reg --unsafe-printable-strings WindowsGuest 'HKLM\System' |
   less

Does the output match running regedit inside the guest?

A recent feature is the ability to dump user registries, so try this, replacing username with the name of a local user in the guest:

 virt-win-reg --unsafe-printable-strings WindowsGuest 'HKEY_USERS\username' |
   less