16.4.5. Augeas and libguestfs Scripting

Combining libguestfs with Augeas can help when writing scripts to manipulate Linux guest virtual machine configuration. For example, the following script uses Augeas to parse the keyboard configuration of a guest virtual machine, and to print out the layout. Note that this example only works with guest virtual machines running Red Hat Enterprise Linux:

#!/bin/bash -
 set -e
 guestname="$1"

 guestfish -d "$1" -i --ro <<'EOF'
   aug-init / 0
   aug-get /files/etc/sysconfig/keyboard/LAYOUT
 EOF

Augeas can also be used to modify configuration files. You can modify the above script to change the keyboard layout:

#!/bin/bash -
 set -e
 guestname="$1"

 guestfish -d "$1" -i <<'EOF'
   aug-init / 0
   aug-set /files/etc/sysconfig/keyboard/LAYOUT '"gb"'
   aug-save
 EOF

Note the three changes between the two scripts:

guestfish can do much more than we can cover in this introductory document. For example, creating disk images from scratch:

guestfish -N fs

Or copying out whole directories from a disk image:

><fs> copy-out /home /tmp/home

For more information see the man page guestfish(1).