#include "guestfs.h"
#include "options.h"
+static void do_suggestion (struct drv *drvs);
+
/* Currently open libguestfs handle. */
guestfs_h *g;
" -r|--ro Access read-only\n"
" --selinux Enable SELinux\n"
" --smp N Enable SMP with N >= 2 virtual CPUs\n"
+ " --suggest Suggest mount commands for this guest\n"
" -v|--verbose Verbose messages\n"
" -V|--version Display version and exit\n"
" -w|--rw Mount read-write\n"
{ "rw", 0, 0, 'w' },
{ "selinux", 0, 0, 0 },
{ "smp", 1, 0, 0 },
+ { "suggest", 0, 0, 0 },
{ "verbose", 0, 0, 'v' },
{ "version", 0, 0, 'V' },
{ 0, 0, 0, 0 }
char *append_full;
int memsize = 0;
int smp = 0;
+ int suggest = 0;
g = guestfs_create ();
if (g == NULL) {
program_name, optarg);
exit (EXIT_FAILURE);
}
+ } else if (STREQ (long_options[option_index].name, "suggest")) {
+ suggest = 1;
} else {
fprintf (stderr, _("%s: unknown long option: %s (%d)\n"),
program_name, long_options[option_index].name, option_index);
}
}
+ /* --suggest flag */
+ if (suggest) {
+ do_suggestion (drvs);
+ exit (EXIT_SUCCESS);
+ }
+
/* These are really constants, but they have to be variables for the
* options parsing code. Assert here that they have known-good
* values.
exit (EXIT_SUCCESS);
}
+static void suggest_filesystems (void);
+
+static int
+compare_keys_len (const void *p1, const void *p2)
+{
+ const char *key1 = * (char * const *) p1;
+ const char *key2 = * (char * const *) p2;
+ return strlen (key1) - strlen (key2);
+}
+
+static size_t
+count_strings (char *const *argv)
+{
+ size_t i;
+
+ for (i = 0; argv[i]; ++i)
+ ;
+ return i;
+}
+
+/* virt-rescue --suggest flag does a kind of inspection on the
+ * drives and suggests mount commands that you should use.
+ */
+static void
+do_suggestion (struct drv *drvs)
+{
+ char **roots;
+ size_t i, j;
+ char *type, *distro, *product_name;
+ int major, minor;
+ char **mps;
+
+ /* For inspection, force add_drives to add the drives read-only. */
+ read_only = 1;
+
+ /* Add drives. */
+ add_drives (drvs, 'a');
+
+ /* Free up data structures, no longer needed after this point. */
+ free_drives (drvs);
+
+ printf (_("Inspecting the virtual machine or disk image ...\n\n"));
+ fflush (stdout);
+
+ if (guestfs_launch (g) == -1)
+ exit (EXIT_FAILURE);
+
+ /* Don't use inspect_mount, since for virt-rescue we should allow
+ * arbitrary disks and disks with more than one OS on them. Let's
+ * do this using the basic API instead.
+ */
+ roots = guestfs_inspect_os (g);
+ if (roots == NULL)
+ exit (EXIT_FAILURE);
+
+ if (roots[0] == NULL) {
+ suggest_filesystems ();
+ return;
+ }
+
+ printf (_("This disk contains one or more operating systems. You can use these mount\n"
+ "commands in virt-rescue (at the ><rescue> prompt) to mount the filesystems.\n\n"));
+
+ for (i = 0; roots[i] != NULL; ++i) {
+ type = guestfs_inspect_get_type (g, roots[i]);
+ distro = guestfs_inspect_get_distro (g, roots[i]);
+ product_name = guestfs_inspect_get_product_name (g, roots[i]);
+ major = guestfs_inspect_get_major_version (g, roots[i]);
+ minor = guestfs_inspect_get_minor_version (g, roots[i]);
+
+ printf (_("# %s is the root of a %s operating system\n"
+ "# type: %s, distro: %s, version: %d.%d\n"
+ "# %s\n\n"),
+ roots[i], type ? : "unknown",
+ type ? : "unknown", distro ? : "unknown", major, minor,
+ product_name ? : "");
+
+ mps = guestfs_inspect_get_mountpoints (g, roots[i]);
+ if (mps == NULL)
+ exit (EXIT_FAILURE);
+
+ /* Sort by key length, shortest key first, so that we end up
+ * mounting the filesystems in the correct order.
+ */
+ qsort (mps, count_strings (mps) / 2, 2 * sizeof (char *),
+ compare_keys_len);
+
+ for (j = 0; mps[j] != NULL; j += 2) {
+ printf ("mount %s /sysroot%s\n", mps[j+1], mps[j]);
+ free (mps[j]);
+ free (mps[j+1]);
+ }
+
+ /* If it's Linux, print the bind-mounts. */
+ if (type && STREQ (type, "linux")) {
+ printf ("mount --bind /dev /sysroot/dev\n");
+ printf ("mount --bind /dev/pts /sysroot/dev/pts\n");
+ printf ("mount --bind /proc /sysroot/proc\n");
+ printf ("mount --bind /sys /sysroot/sys\n");
+ }
+
+ printf ("\n");
+
+ free (type);
+ free (distro);
+ free (product_name);
+ free (roots[i]);
+ }
+
+ free (roots);
+}
+
+/* Inspection failed, so it doesn't contain any OS that we recognise.
+ * However there might still be filesystems so print some suggestions
+ * for those.
+ */
+static void
+suggest_filesystems (void)
+{
+ char **fses;
+ size_t i;
+
+ fses = guestfs_list_filesystems (g);
+ if (fses == NULL)
+ exit (EXIT_FAILURE);
+
+ if (fses[0] == NULL) {
+ printf (_("This disk contains no filesystems that we recognize.\n\n"
+ "However you can still use virt-rescue on the disk image, to try to mount\n"
+ "filesystems that are not recognized by libguestfs, or to create partitions,\n"
+ "logical volumes and filesystems on a blank disk.\n"));
+ return;
+ }
+
+ printf (_("This disk contains one or more filesystems, but we don't recognize any\n"
+ "operating system. You can use these mount commands in virt-rescue (at the\n"
+ "><rescue> prompt) to mount these filesystems.\n\n"));
+
+ for (i = 0; fses[i] != NULL; i += 2) {
+ printf (_("# %s has type '%s'\n"), fses[i], fses[i+1]);
+
+ if (STRNEQ (fses[i+1], "swap") && STRNEQ (fses[i+1], "unknown"))
+ printf ("mount %s /sysroot\n", fses[i]);
+
+ printf ("\n");
+
+ free (fses[i]);
+ free (fses[i+1]);
+ }
+ free (fses);
+}
+
+
/* The following was a nice idea, but in fact it doesn't work. This is
* because qemu has some (broken) pty emulation itself.
*/
virt-rescue [--options] -a disk.img [-a disk.img ...]
+ virt-rescue --suggest (-d domname | -a disk.img ...)
+
Old style:
virt-rescue [--options] domname
hand. There is an empty directory called C</sysroot> where you can
mount filesystems.
-In the example below, we list logical volumes, then choose one to
-mount under C</sysroot>:
+You can get virt-rescue to suggest mount commands for you by using the
+I<--suggest> option (in another terminal):
+
+ $ virt-rescue --suggest -d Fedora15
+ Inspecting the virtual machine or disk image ...
+
+ This disk contains one or more operating systems. You can use these
+ mount commands in virt-rescue (at the ><rescue> prompt) to mount the
+ filesystems.
+
+ # /dev/vg_f15x32/lv_root is the root of a linux operating system
+ # type: linux, distro: fedora, version: 15.0
+ # Fedora release 15 (Lovelock)
+
+ mount /dev/vg_f15x32/lv_root /sysroot/
+ mount /dev/vda1 /sysroot/boot
+ mount --bind /dev /sysroot/dev
+ mount --bind /dev/pts /sysroot/dev/pts
+ mount --bind /proc /sysroot/proc
+ mount --bind /sys /sysroot/sys
+
+Another way is to list the logical volumes (with L<lvs(8)>) and
+partitions (with L<parted(8)>) and mount them by hand:
><rescue> lvs
LV VG Attr LSize Origin Snap% Move Log Copy% Convert
- lv_root vg_f11x64 -wi-a- 8.83G
- lv_swap vg_f11x64 -wi-a- 992.00M
- ><rescue> mount /dev/vg_f11x64/lv_root /sysroot
+ lv_root vg_f15x32 -wi-a- 8.83G
+ lv_swap vg_f15x32 -wi-a- 992.00M
+ ><rescue> mount /dev/vg_f15x32/lv_root /sysroot
+ ><rescue> mount /dev/vda1 /sysroot/boot
><rescue> ls /sysroot
-If you don't know what filesystems are available on the virtual
-machine then you can use commands such as L<parted(8)> and L<lvs(8)>
-to find out.
+Another command to list available filesystems is
+L<virt-filesystems(1)>.
+
+To run commands in a Linux guest (for example, grub), you should
+chroot into the /sysroot directory first:
+
+ ><rescue> chroot /sysroot
=head2 NOTES
Enable N E<ge> 2 virtual CPUs in the rescue appliance.
+=item B<--suggest>
+
+Inspect the disk image and suggest what mount commands should be used
+to mount the disks. You should use the I<--suggest> option in a
+second terminal, then paste the commands into another virt-rescue.
+
+This option implies I<--ro> and is safe to use even if the guest is up
+or if another virt-rescue is running.
+
=item B<-v>
=item B<--verbose>
L<guestfish(1)>,
L<virt-cat(1)>,
L<virt-edit(1)>,
+L<virt-filesystems(1)>,
L<http://libguestfs.org/>.
=head1 AUTHOR
git.annexia.org / libguestfs.git / commitdiff