1virt-sysprep(1) Virtualization Support virt-sysprep(1)
2
6 virt-sysprep - Reset, unconfigure or customize a virtual machine so
7 clones can be made
8
10 virt-sysprep [--options] -d domname
11 virt-sysprep [--options] -a disk.img [-a disk.img ...]
13
15 Using "virt-sysprep" on live virtual machines, or concurrently with
16 other disk editing tools, can be dangerous, potentially causing disk
17 corruption. The virtual machine must be shut down before you use this
18 command, and disk images must not be edited concurrently.
19
21 Virt-sysprep can reset or unconfigure a virtual machine so that clones
22 can be made from it. Steps in this process include removing SSH host
23 keys, removing persistent network MAC configuration, and removing user
24 accounts. Virt-sysprep can also customize a virtual machine, for
25 instance by adding SSH keys, users or logos. Each step can be enabled
26 or disabled as required.
27 Virt-sysprep modifies the guest or disk image in place. The guest must
29 be shut down. If you want to preserve the existing contents of the
30 guest, you must snapshot, copy or clone the disk first. See "COPYING
31 AND CLONING" below.
32 You do not need to run virt-sysprep as root. In fact we'd generally
34 recommend that you don't. The time you might want to run it as root is
35 when you need root in order to access the disk image, but even in this
36 case it would be better to change the permissions on the disk image to
37 be writable as the non-root user running virt-sysprep.
38 "Sysprep" stands for "system preparation" tool. The name comes from
40 the Microsoft program sysprep.exe which is used to unconfigure Windows
41 machines in preparation for cloning them. Having said that, virt-
42 sysprep does not currently work on Microsoft Windows guests. We plan
43 to support Windows sysprepping in a future version, and we already have
44 code to do it.
45
47 --help
48 Display brief help.
49 -a file
51 --add file
52 Add file which should be a disk image from a virtual machine.
53 The format of the disk image is auto-detected. To override this
55 and force a particular format use the --format option.
56 -a URI
58 --add URI
59 Add a remote disk. The URI format is compatible with guestfish.
60 See "ADDING REMOTE STORAGE" in guestfish(1).
61 --colors
63 --colours
64 Use ANSI colour sequences to colourize messages. This is the
65 default when the output is a tty. If the output of the program is
66 redirected to a file, ANSI colour sequences are disabled unless you
67 use this option.
68 -c URI
70 --connect URI
71 If using libvirt, connect to the given URI. If omitted, then we
72 connect to the default libvirt hypervisor.
73 If you specify guest block devices directly (-a), then libvirt is
75 not used at all.
76 -d guest
78 --domain guest
79 Add all the disks from the named libvirt guest. Domain UUIDs can
80 be used instead of names.
81 -n
83 --dry-run
84 Perform a read-only "dry run" on the guest. This runs the sysprep
85 operation, but throws away any changes to the disk at the end.
86 --enable operations
88 Choose which sysprep operations to perform. Give a comma-separated
89 list of operations, for example:
90 --enable ssh-hostkeys,udev-persistent-net
92 would enable ONLY "ssh-hostkeys" and "udev-persistent-net"
94 operations.
95 If the --enable option is not given, then we default to trying most
97 sysprep operations (see --list-operations to show which are
98 enabled).
99 Regardless of the --enable option, sysprep operations are skipped
101 for some guest types.
102 Use --list-operations to list operations supported by a particular
104 version of virt-sysprep.
105 See "OPERATIONS" below for a list and an explanation of each
107 operation.
108 --operation operations
110 --operations operations
111 Choose which sysprep operations to perform. Give a comma-separated
112 list of operations, for example:
113 --operations ssh-hostkeys,udev-persistent-net
115 would enable ONLY "ssh-hostkeys" and "udev-persistent-net"
117 operations.
118 --operations allows you to enable and disable any operation,
120 including the default ones (which would be tried when specifying
121 neither --operations nor --enable) and all the available ones;
122 prepending a "-" in front of an operation name removes it from the
123 list of enabled operations, while the meta-names "defaults" and
124 "all" represent respectively the operations enabled by default and
125 all the available ones. For example:
126 --operations firewall-rules,defaults,-tmp-files
128 would enable the "firewall-rules" operation (regardless whether it
130 is enabled by default), all the default ones, and disable the
131 "tmp-files" operation.
132 --operations can be specified multiple times; the first time the
134 set of enabled operations is empty, while any further --operations
135 affects the operations enabled so far.
136 If the --operations option is not given, then we default to trying
138 most sysprep operations (see --list-operations to show which are
139 enabled).
140 Regardless of the --operations option, sysprep operations are
142 skipped for some guest types.
143 Use --list-operations to list operations supported by a particular
145 version of virt-sysprep.
146 See "OPERATIONS" below for a list and an explanation of each
148 operation.
149 --echo-keys
151 When prompting for keys and passphrases, virt-sysprep normally
152 turns echoing off so you cannot see what you are typing. If you
153 are not worried about Tempest attacks and there is no one else in
154 the room you can specify this flag to see what you are typing.
155 --format raw|qcow2|..
157 --format auto
158 The default for the -a option is to auto-detect the format of the
159 disk image. Using this forces the disk format for -a options which
160 follow on the command line. Using --format auto switches back to
161 auto-detection for subsequent -a options.
162 For example:
164 virt-sysprep --format raw -a disk.img
166 forces raw format (no auto-detection) for disk.img.
168 virt-sysprep --format raw -a disk.img --format auto -a another.img
170 forces raw format (no auto-detection) for disk.img and reverts to
172 auto-detection for another.img.
173 If you have untrusted raw-format guest disk images, you should use
175 this option to specify the disk format. This avoids a possible
176 security problem with malicious guests (CVE-2010-3851).
177 --key SELECTOR
179 Specify a key for LUKS, to automatically open a LUKS device when
180 using the inspection. "ID" can be either the libguestfs device
181 name, or the UUID of the LUKS device.
182 --key "ID":key:KEY_STRING
184 Use the specified "KEY_STRING" as passphrase.
185 --key "ID":file:FILENAME
187 Read the passphrase from FILENAME.
188 --key "ID":clevis
190 Attempt passphrase-less unlocking for "ID" with Clevis, over
191 the network. Please refer to "ENCRYPTED DISKS" in guestfs(3)
192 for more information on network-bound disk encryption (NBDE).
193 Note that if any such option is present on the command line,
195 QEMU user networking will be automatically enabled for the
196 libguestfs appliance.
197 --keys-from-stdin
199 Read key or passphrase parameters from stdin. The default is to
200 try to read passphrases from the user by opening /dev/tty.
201 If there are multiple encrypted devices then you may need to supply
203 multiple keys on stdin, one per line.
204 --list-operations
206 List the operations supported by the virt-sysprep program.
207 These are listed one per line, with one or more single-space-
209 separated fields, eg:
210 $ virt-sysprep --list-operations
212 bash-history * Remove the bash history in the guest
213 cron-spool * Remove user at-jobs and cron-jobs
214 dhcp-client-state * Remove DHCP client leases
215 dhcp-server-state * Remove DHCP server leases
216 [etc]
217 The first field is the operation name, which can be supplied to
219 --enable. The second field is a "*" character if the operation is
220 enabled by default or blank if not. Subsequent fields on the same
221 line are the description of the operation.
222 Before libguestfs 1.17.33 only the first (operation name) field was
224 shown and all operations were enabled by default.
225 --mount-options mp:opts[;mp:opts;...]
227 Set the mount options used when libguestfs opens the disk image.
228 Note this has no effect on the guest. It is used when opening
229 certain guests such as ones using the UFS (BSD) filesystem.
230 Use a semicolon-separated list of "mountpoint:options" pairs. You
232 may need to quote this list to protect it from the shell.
233 For example:
235 --mount-options "/:noatime"
237 will mount the root directory with "notime". This example:
239 --mount-options "/:noatime;/var:rw,nodiratime"
241 will do the same, plus mount /var with "rw,nodiratime".
243 -q
245 --quiet
246 Don’t print log messages.
247 To enable detailed logging of individual file operations, use -x.
249 --network
251 --no-network
252 Enable or disable network access from the guest during the
253 installation.
254 In virt-sysprep, the network is disabled by default. You must use
256 --network to enable it, in order that options such as --install or
257 --update will work.
258 virt-builder(1) has more information about the security advantages
260 of disabling the network.
261 -v
263 --verbose
264 Enable verbose messages for debugging.
265 -V
267 --version
268 Display version number and exit.
269 --wrap
271 Wrap error, warning, and informative messages. This is the default
272 when the output is a tty. If the output of the program is
273 redirected to a file, wrapping is disabled unless you use this
274 option.
275 -x Enable tracing of libguestfs API calls.
277 --append-line FILE:LINE (see "customize" below)
279 Append a single line of text to the "FILE". If the file does not
280 already end with a newline, then one is added before the appended
281 line. Also a newline is added to the end of the "LINE" string
282 automatically.
283 For example (assuming ordinary shell quoting) this command:
285 --append-line '/etc/hosts:10.0.0.1 foo'
287 will add either "10.0.0.1 foo⏎" or "⏎10.0.0.1 foo⏎" to the file,
289 the latter only if the existing file does not already end with a
290 newline.
291 "⏎" represents a newline character, which is guessed by looking at
293 the existing content of the file, so this command does the right
294 thing for files using Unix or Windows line endings. It also works
295 for empty or non-existent files.
296 To insert several lines, use the same option several times:
298 --append-line '/etc/hosts:10.0.0.1 foo'
300 --append-line '/etc/hosts:10.0.0.2 bar'
301 To insert a blank line before the appended line, do:
303 --append-line '/etc/hosts:'
305 --append-line '/etc/hosts:10.0.0.1 foo'
306 --chmod PERMISSIONS:FILE (see "customize" below)
308 Change the permissions of "FILE" to "PERMISSIONS".
309 Note: "PERMISSIONS" by default would be decimal, unless you prefix
311 it with 0 to get octal, ie. use 0700 not 700.
312 --commands-from-file FILENAME (see "customize" below)
314 Read the customize commands from a file, one (and its arguments)
315 each line.
316 Each line contains a single customization command and its
318 arguments, for example:
319 delete /some/file
321 install some-package
322 password some-user:password:its-new-password
323 Empty lines are ignored, and lines starting with "#" are comments
325 and are ignored as well. Furthermore, arguments can be spread
326 across multiple lines, by adding a "\" (continuation character) at
327 the of a line, for example
328 edit /some/file:\
330 s/^OPT=.*/OPT=ok/
331 The commands are handled in the same order as they are in the file,
333 as if they were specified as --delete /some/file on the command
334 line.
335 --copy SOURCE:DEST (see "customize" below)
337 Copy files or directories recursively inside the guest.
338 Wildcards cannot be used.
340 --copy-in LOCALPATH:REMOTEDIR (see "customize" below)
342 Copy local files or directories recursively into the disk image,
343 placing them in the directory "REMOTEDIR" (which must exist).
344 Wildcards cannot be used.
346 --delete PATH (see "customize" below)
348 Delete a file from the guest. Or delete a directory (and all its
349 contents, recursively).
350 You can use shell glob characters in the specified path. Be
352 careful to escape glob characters from the host shell, if that is
353 required. For example:
354 virt-customize --delete '/var/log/*.log'.
356 See also: --upload, --scrub.
358 --edit FILE:EXPR (see "customize" below)
360 Edit "FILE" using the Perl expression "EXPR".
361 Be careful to properly quote the expression to prevent it from
363 being altered by the shell.
364 Note that this option is only available when Perl 5 is installed.
366 See "NON-INTERACTIVE EDITING" in virt-edit(1).
368 --firstboot SCRIPT (see "customize" below)
370 Install "SCRIPT" inside the guest, so that when the guest first
371 boots up, the script runs (as root, late in the boot process).
372 The script is automatically chmod +x after installation in the
374 guest.
375 The alternative version --firstboot-command is the same, but it
377 conveniently wraps the command up in a single line script for you.
378 You can have multiple --firstboot options. They run in the same
380 order that they appear on the command line.
381 Please take a look at "FIRST BOOT SCRIPTS" in virt-builder(1) for
383 more information and caveats about the first boot scripts.
384 See also --run.
386 --firstboot-command 'CMD+ARGS' (see "customize" below)
388 Run command (and arguments) inside the guest when the guest first
389 boots up (as root, late in the boot process).
390 You can have multiple --firstboot options. They run in the same
392 order that they appear on the command line.
393 Please take a look at "FIRST BOOT SCRIPTS" in virt-builder(1) for
395 more information and caveats about the first boot scripts.
396 See also --run.
398 --firstboot-install PKG,PKG.. (see "customize" below)
400 Install the named packages (a comma-separated list). These are
401 installed when the guest first boots using the guest’s package
402 manager (eg. apt, yum, etc.) and the guest’s network connection.
403 For an overview on the different ways to install packages, see
405 "INSTALLING PACKAGES" in virt-builder(1).
406 --hostname HOSTNAME (see "customize" below)
408 Set the hostname of the guest to "HOSTNAME". You can use a dotted
409 hostname.domainname (FQDN) if you want.
410 --install PKG,PKG.. (see "customize" below)
412 Install the named packages (a comma-separated list). These are
413 installed during the image build using the guest’s package manager
414 (eg. apt, yum, etc.) and the host’s network connection.
415 For an overview on the different ways to install packages, see
417 "INSTALLING PACKAGES" in virt-builder(1).
418 See also --update, --uninstall.
420 --keep-user-accounts USERS (see "user-account" below)
422 The user accounts to be kept in the guest. The value of this
423 option is a list of user names separated by comma, where specifying
424 an user means it is going to be kept. For example:
425 --keep-user-accounts mary
427 would keep the user account "mary".
429 This option can be specified multiple times.
431 --link TARGET:LINK[:LINK..] (see "customize" below)
433 Create symbolic link(s) in the guest, starting at "LINK" and
434 pointing at "TARGET".
435 --mkdir DIR (see "customize" below)
437 Create a directory in the guest.
438 This uses "mkdir -p" so any intermediate directories are created,
440 and it also works if the directory already exists.
441 --move SOURCE:DEST (see "customize" below)
443 Move files or directories inside the guest.
444 Wildcards cannot be used.
446 --no-logfile (see "customize" below)
448 Scrub "builder.log" (log file from build commands) from the image
449 after building is complete. If you don't want to reveal precisely
450 how the image was built, use this option.
451 See also: "LOG FILE".
453 --no-selinux-relabel (see "customize" below)
455 Do not attempt to correct the SELinux labels of files in the guest.
456 In such guests that support SELinux, customization automatically
458 relabels files so that they have the correct SELinux label. (The
459 relabeling is performed immediately, but if the operation fails,
460 customization will instead touch /.autorelabel on the image to
461 schedule a relabel operation for the next time the image boots.)
462 This option disables the automatic relabeling.
463 The option is a no-op for guests that do not support SELinux.
465 --password USER:SELECTOR (see "customize" below)
467 Set the password for "USER". (Note this option does not create the
468 user account).
469 See "USERS AND PASSWORDS" in virt-builder(1) for the format of the
471 "SELECTOR" field, and also how to set up user accounts.
472 --password-crypto md5|sha256|sha512 (see "customize" below)
474 When the virt tools change or set a password in the guest, this
475 option sets the password encryption of that password to "md5",
476 "sha256" or "sha512".
477 "sha256" and "sha512" require glibc ≥ 2.7 (check crypt(3) inside
479 the guest).
480 "md5" will work with relatively old Linux guests (eg. RHEL 3), but
482 is not secure against modern attacks.
483 The default is "sha512" unless libguestfs detects an old guest that
485 didn't have support for SHA-512, in which case it will use "md5".
486 You can override libguestfs by specifying this option.
487 Note this does not change the default password encryption used by
489 the guest when you create new user accounts inside the guest. If
490 you want to do that, then you should use the --edit option to
491 modify "/etc/sysconfig/authconfig" (Fedora, RHEL) or
492 "/etc/pam.d/common-password" (Debian, Ubuntu).
493 --remove-user-accounts USERS (see "user-account" below)
495 The user accounts to be removed from the guest. The value of this
496 option is a list of user names separated by comma, where specifying
497 an user means it is going to be removed. For example:
498 --remove-user-accounts bob,eve
500 would only remove the user accounts "bob" and "eve".
502 This option can be specified multiple times.
504 --root-password SELECTOR (see "customize" below)
506 Set the root password.
507 See "USERS AND PASSWORDS" in virt-builder(1) for the format of the
509 "SELECTOR" field, and also how to set up user accounts.
510 Note: In virt-builder, if you don't set --root-password then the
512 guest is given a random root password.
513 --run SCRIPT (see "customize" below)
515 Run the shell script (or any program) called "SCRIPT" on the disk
516 image. The script runs virtualized inside a small appliance,
517 chrooted into the guest filesystem.
518 The script is automatically chmod +x.
520 If libguestfs supports it then a limited network connection is
522 available but it only allows outgoing network connections. You can
523 also attach data disks (eg. ISO files) as another way to provide
524 data (eg. software packages) to the script without needing a
525 network connection (--attach). You can also upload data files
526 (--upload).
527 You can have multiple --run options. They run in the same order
529 that they appear on the command line.
530 See also: --firstboot, --attach, --upload.
532 --run-command 'CMD+ARGS' (see "customize" below)
534 Run the command and arguments on the disk image. The command runs
535 virtualized inside a small appliance, chrooted into the guest
536 filesystem.
537 If libguestfs supports it then a limited network connection is
539 available but it only allows outgoing network connections. You can
540 also attach data disks (eg. ISO files) as another way to provide
541 data (eg. software packages) to the script without needing a
542 network connection (--attach). You can also upload data files
543 (--upload).
544 You can have multiple --run-command options. They run in the same
546 order that they appear on the command line.
547 See also: --firstboot, --attach, --upload.
549 --script SCRIPT (see "script" below)
551 Run the named "SCRIPT" (a shell script or program) against the
552 guest. The script can be any program on the host. The script’s
553 current directory will be the guest’s root directory.
554 Note: If the script is not on the $PATH, then you must give the
556 full absolute path to the script.
557 --scriptdir SCRIPTDIR (see "script" below)
559 The mount point (an empty directory on the host) used when the
560 "script" operation is enabled and one or more scripts are specified
561 using --script parameter(s).
562 Note: "SCRIPTDIR" must be an absolute path.
564 If --scriptdir is not specified then a temporary mountpoint will be
566 created.
567 --scrub FILE (see "customize" below)
569 Scrub a file from the guest. This is like --delete except that:
570 • It scrubs the data so a guest could not recover it.
572 • It cannot delete directories, only regular files.
574 --selinux-relabel (see "customize" below)
576 This is a compatibility option that does nothing.
577 --sm-attach SELECTOR (see "customize" below)
579 Attach to a pool using "subscription-manager".
580 See "SUBSCRIPTION-MANAGER" in virt-builder(1) for the format of the
582 "SELECTOR" field.
583 --sm-credentials SELECTOR (see "customize" below)
585 Set the credentials for "subscription-manager".
586 See "SUBSCRIPTION-MANAGER" in virt-builder(1) for the format of the
588 "SELECTOR" field.
589 --sm-register (see "customize" below)
591 Register the guest using "subscription-manager".
592 This requires credentials being set using --sm-credentials.
594 --sm-remove (see "customize" below)
596 Remove all the subscriptions from the guest using
597 "subscription-manager".
598 --sm-unregister (see "customize" below)
600 Unregister the guest using "subscription-manager".
601 --ssh-inject USER[:SELECTOR] (see "customize" below)
603 Inject an ssh key so the given "USER" will be able to log in over
604 ssh without supplying a password. The "USER" must exist already in
605 the guest.
606 See "SSH KEYS" in virt-builder(1) for the format of the "SELECTOR"
608 field.
609 You can have multiple --ssh-inject options, for different users and
611 also for more keys for each user.
612 --timezone TIMEZONE (see "customize" below)
614 Set the default timezone of the guest to "TIMEZONE". Use a
615 location string like "Europe/London"
616 --touch FILE (see "customize" below)
618 This command performs a touch(1)-like operation on "FILE".
619 --truncate FILE (see "customize" below)
621 This command truncates "FILE" to a zero-length file. The file must
622 exist already.
623 --truncate-recursive PATH (see "customize" below)
625 This command recursively truncates all files under "PATH" to zero-
626 length.
627 --uninstall PKG,PKG.. (see "customize" below)
629 Uninstall the named packages (a comma-separated list). These are
630 removed during the image build using the guest’s package manager
631 (eg. apt, yum, etc.). Dependent packages may also need to be
632 uninstalled to satisfy the request.
633 See also --install, --update.
635 --update (see "customize" below)
637 Do the equivalent of "yum update", "apt-get upgrade", or whatever
638 command is required to update the packages already installed in the
639 template to their latest versions.
640 See also --install, --uninstall.
642 --upload FILE:DEST (see "customize" below)
644 Upload local file "FILE" to destination "DEST" in the disk image.
645 File owner and permissions from the original are preserved, so you
646 should set them to what you want them to be in the disk image.
647 "DEST" could be the final filename. This can be used to rename the
649 file on upload.
650 If "DEST" is a directory name (which must already exist in the
652 guest) then the file is uploaded into that directory, and it keeps
653 the same name as on the local filesystem.
654 See also: --mkdir, --delete, --scrub.
656 --write FILE:CONTENT (see "customize" below)
658 Write "CONTENT" to "FILE".
659
661 If the --enable/--operations option is not given, then most sysprep
662 operations are enabled.
663 Use "virt-sysprep --list-operations" to list all operations for your
665 virt-sysprep binary. The ones which are enabled by default are marked
666 with a "*" character. Regardless of the --enable/--operations options,
667 sysprep operations are skipped for some guest types.
668 Operations can be individually enabled using the --enable/--operations
670 options. Use a comma-separated list, for example:
671 virt-sysprep --operations ssh-hostkeys,udev-persistent-net [etc..]
673 Future versions of virt-sysprep may add more operations. If you are
675 using virt-sysprep and want predictable behaviour, specify only the
676 operations that you want to have enabled.
677 "*" = enabled by default when no --enable/--operations option is given.
679 abrt-data *
681 Remove the crash data generated by ABRT.
682 Remove the automatically generated ABRT crash data in
684 "/var/spool/abrt/".
685 backup-files *
687 Remove editor backup files from the guest.
688 The following files are removed from anywhere in the guest filesystem:
690 · *.bak
692 · *~
694 On Linux and Unix operating systems, only the following filesystems
696 will be examined:
697 · /etc
699 · /root
701 · /srv
703 · /tmp
705 · /var
707 bash-history *
709 Remove the bash history in the guest.
710 Remove the bash history of user "root" and any other users who have a
712 ".bash_history" file in their home directory.
713 Notes on bash-history
715 Currently this only looks in "/root" and "/home/*" for home
717 directories, so users with home directories in other locations won't
718 have the bash history removed.
719 blkid-tab *
721 Remove blkid tab in the guest.
722 ca-certificates
724 Remove CA certificates in the guest.
725 In case any certificate is removed, the system CA store is updated.
727 crash-data *
729 Remove the crash data generated by kexec-tools.
730 Remove the automatically generated kdump kernel crash data.
732 cron-spool *
734 Remove user at-jobs and cron-jobs.
735 customize *
737 Customize the guest.
738 Customize the guest by providing virt-customize(1) options for
740 installing packages, editing files and so on.
741 dhcp-client-state *
743 Remove DHCP client leases.
744 dhcp-server-state *
746 Remove DHCP server leases.
747 dovecot-data *
749 Remove Dovecot (mail server) data.
750 firewall-rules
752 Remove the firewall rules.
753 This removes custom firewall rules by removing
755 "/etc/sysconfig/iptables" or custom firewalld configuration in
756 "/etc/firewalld/*/*".
757 Note this is not enabled by default since it may expose guests to
759 exploits. Use with care.
760 flag-reconfiguration
762 Flag the system for reconfiguration.
763 For Linux guests, this touches "/.unconfigured", which causes the first
765 boot to interactively query the user for settings such as the root
766 password and timezone.
767 fs-uuids
769 Change filesystem UUIDs.
770 On guests and filesystem types where this is supported, new random
772 UUIDs are generated and assigned to filesystems.
773 Notes on fs-uuids
775 The fs-uuids operation is disabled by default because it does not yet
777 find and update all the places in the guest that use the UUIDs. For
778 example "/etc/fstab" or the bootloader. Enabling this operation is
779 more likely than not to make your guest unbootable.
780 See: https://bugzilla.redhat.com/show_bug.cgi?id=991641
782 ipa-client *
784 Remove the IPA files.
785 Remove all the files related to an IPA (Identity, Policy, Audit)
787 system. This effectively unenrolls the guest from an IPA server
788 without interacting with it.
789 This operation does not run "ipa-client".
791 kerberos-data
793 Remove Kerberos data in the guest.
794 kerberos-hostkeytab *
796 Remove the Kerberos host keytab file in the guest.
797 logfiles *
799 Remove many log files from the guest.
800 On Linux the following files are removed:
802 · /etc/Pegasus/*.cnf
804 · /etc/Pegasus/*.crt
806 · /etc/Pegasus/*.csr
808 · /etc/Pegasus/*.pem
810 · /etc/Pegasus/*.srl
812 · /root/anaconda-ks.cfg
814 · /root/anaconda-post.log
816 · /root/initial-setup-ks.cfg
818 · /root/install.log
820 · /root/install.log.syslog
822 · /root/original-ks.cfg
824 · /var/cache/fontconfig/*
826 · /var/cache/gdm/*
828 · /var/cache/man/*
830 · /var/lib/AccountService/users/*
832 · /var/lib/fprint/*
834 · /var/lib/logrotate.status
836 · /var/log/*.log*
838 · /var/log/BackupPC/LOG
840 · /var/log/ConsoleKit/*
842 · /var/log/anaconda.syslog
844 · /var/log/anaconda/*
846 · /var/log/apache2/*_log
848 · /var/log/apache2/*_log-*
850 · /var/log/apt/*
852 · /var/log/aptitude*
854 · /var/log/audit/*
856 · /var/log/btmp*
858 · /var/log/ceph/*.log
860 · /var/log/chrony/*.log
862 · /var/log/cron*
864 · /var/log/cups/*_log*
866 · /var/log/debug*
868 · /var/log/dmesg*
870 · /var/log/exim4/*
872 · /var/log/faillog*
874 · /var/log/firewalld*
876 · /var/log/gdm/*
878 · /var/log/glusterfs/*glusterd.vol.log
880 · /var/log/glusterfs/glusterfs.log
882 · /var/log/grubby*
884 · /var/log/httpd/*log
886 · /var/log/installer/*
888 · /var/log/jetty/jetty-console.log
890 · /var/log/journal/*
892 · /var/log/lastlog*
894 · /var/log/libvirt/libvirtd.log
896 · /var/log/libvirt/libxl/*.log
898 · /var/log/libvirt/lxc/*.log
900 · /var/log/libvirt/qemu/*.log
902 · /var/log/libvirt/uml/*.log
904 · /var/log/lightdm/*
906 · /var/log/mail/*
908 · /var/log/maillog*
910 · /var/log/messages*
912 · /var/log/ntp
914 · /var/log/ntpstats/*
916 · /var/log/ppp/connect-errors
918 · /var/log/rhsm/*
920 · /var/log/sa/*
922 · /var/log/secure*
924 · /var/log/setroubleshoot/*.log
926 · /var/log/spooler*
928 · /var/log/squid/*.log
930 · /var/log/syslog*
932 · /var/log/tallylog*
934 · /var/log/tuned/tuned.log
936 · /var/log/wtmp*
938 · /var/log/xferlog*
940 · /var/named/data/named.run
942 lvm-system-devices *
944 Remove LVM2 system.devices file.
945 On Linux guests, LVM2's scanning for physical volumes (PVs) may be
947 restricted to those block devices whose WWIDs are listed in
948 "/etc/lvm/devices/system.devices". When cloning VMs, WWIDs may change,
949 breaking "lvm pvscan". Remove "/etc/lvm/devices/system.devices".
950 lvm-uuids *
952 Change LVM2 PV and VG UUIDs.
953 On Linux guests that have LVM2 physical volumes (PVs) or volume groups
955 (VGs), new random UUIDs are generated and assigned to those PVs and
956 VGs.
957 machine-id *
959 Remove the local machine ID.
960 The machine ID is usually generated from a random source during system
962 installation and stays constant for all subsequent boots. Optionally,
963 for stateless systems it is generated during runtime at boot if it is
964 found to be empty.
965 mail-spool *
967 Remove email from the local mail spool directory.
968 net-hostname *
970 Remove HOSTNAME and DHCP_HOSTNAME in network interface configuration.
971 For Fedora and Red Hat Enterprise Linux, this is removed from "ifcfg-*"
973 files.
974 net-hwaddr *
976 Remove HWADDR (hard-coded MAC address) configuration.
977 For Fedora and Red Hat Enterprise Linux, this is removed from "ifcfg-*"
979 files.
980 net-nmconn *
982 Remove system-local NetworkManager connection profiles (keyfiles).
983 On Fedora and Red Hat Enterprise Linux, remove the
985 "/etc/NetworkManager/system-connections/*.nmconnection" files.
986 pacct-log *
988 Remove the process accounting log files.
989 The system wide process accounting will store to the pacct log files if
991 the process accounting is on.
992 package-manager-cache *
994 Remove package manager cache.
995 pam-data *
997 Remove the PAM data in the guest.
998 passwd-backups *
1000 Remove /etc/passwd- and similar backup files.
1001 On Linux the following files are removed:
1003 · /etc/group-
1005 · /etc/gshadow-
1007 · /etc/passwd-
1009 · /etc/shadow-
1011 · /etc/subgid-
1013 · /etc/subuid-
1015 puppet-data-log *
1017 Remove the data and log files of puppet.
1018 rh-subscription-manager *
1020 Remove the RH subscription manager files.
1021 rhn-systemid *
1023 Remove the RHN system ID.
1024 rpm-db *
1026 Remove host-specific RPM database files.
1027 Remove host-specific RPM database files and locks. RPM will recreate
1029 these files automatically if needed.
1030 samba-db-log *
1032 Remove the database and log files of Samba.
1033 script *
1035 Run arbitrary scripts against the guest.
1036 The "script" module lets you run arbitrary shell scripts or programs
1038 against the guest.
1039 Note this feature requires FUSE support. You may have to enable this
1041 in your host, for example by adding the current user to the "fuse"
1042 group, or by loading a kernel module.
1043 Use one or more --script parameters to specify scripts or programs that
1045 will be run against the guest.
1046 The script or program is run with its current directory being the
1048 guest’s root directory, so relative paths should be used. For example:
1049 "rm etc/resolv.conf" in the script would remove a Linux guest’s DNS
1050 configuration file, but "rm /etc/resolv.conf" would (try to) remove the
1051 host’s file.
1052 Normally a temporary mount point for the guest is used, but you can
1054 choose a specific one by using the --scriptdir parameter.
1055 Note: This is different from --firstboot scripts (which run in the
1057 context of the guest when it is booting first time). --script scripts
1058 run on the host, not in the guest.
1059 smolt-uuid *
1061 Remove the Smolt hardware UUID.
1062 ssh-hostkeys *
1064 Remove the SSH host keys in the guest.
1065 The SSH host keys are regenerated (differently) next time the guest is
1067 booted.
1068 If, after cloning, the guest gets the same IP address, ssh will give
1070 you a stark warning about the host key changing:
1071 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1073 @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
1074 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1075 IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
1076 ssh-userdir *
1078 Remove ".ssh" directories in the guest.
1079 Remove the ".ssh" directory of user "root" and any other users who have
1081 a ".ssh" directory in their home directory.
1082 Notes on ssh-userdir
1084 Currently this only looks in "/root" and "/home/*" for home
1086 directories, so users with home directories in other locations won't
1087 have the ssh files removed.
1088 sssd-db-log *
1090 Remove the database and log files of sssd.
1091 tmp-files *
1093 Remove temporary files.
1094 This removes temporary files under "/tmp" and "/var/tmp".
1096 udev-persistent-net *
1098 Remove udev persistent net rules.
1099 Remove udev persistent net rules which map the guest’s existing MAC
1101 address to a fixed ethernet device (eg. eth0).
1102 After a guest is cloned, the MAC address usually changes. Since the
1104 old MAC address occupies the old name (eg. eth0), this means the fresh
1105 MAC address is assigned to a new name (eg. eth1) and this is usually
1106 undesirable. Erasing the udev persistent net rules avoids this.
1107 user-account
1109 Remove the user accounts in the guest.
1110 By default remove all the user accounts and their home directories.
1112 The "root" account is not removed.
1113 See the --remove-user-accounts parameter for a way to specify how to
1115 remove only some users, or to not remove some others.
1116 utmp *
1118 Remove the utmp file.
1119 This file records who is currently logged in on a machine. In modern
1121 Linux distros it is stored in a ramdisk and hence not part of the
1122 virtual machine’s disk, but it was stored on disk in older distros.
1123 yum-uuid *
1125 Remove the yum UUID.
1126 Yum creates a fresh UUID the next time it runs when it notices that the
1128 original UUID has been erased.
1129
1131 Virt-sysprep can be used as part of a process of cloning guests, or to
1132 prepare a template from which guests can be cloned. There are many
1133 different ways to achieve this using the virt tools, and this section
1134 is just an introduction.
1135 A virtual machine (when switched off) consists of two parts:
1137 configuration
1139 The configuration or description of the guest. eg. The libvirt XML
1140 (see "virsh dumpxml"), the running configuration of the guest, or
1141 another external format like OVF.
1142 Some configuration items that might need to be changed:
1144 • name
1146 • UUID
1148 • path to block device(s)
1150 • network card MAC address
1152 block device(s)
1154 One or more hard disk images, themselves containing files,
1155 directories, applications, kernels, configuration, etc.
1156 Some things inside the block devices that might need to be changed:
1158 • hostname and other net configuration
1160 • UUID
1162 • SSH host keys
1164 • Windows unique security ID (SID)
1166 • Puppet registration
1168 COPYING THE BLOCK DEVICE
1170 Starting with an original guest, you probably wish to copy the guest
1171 block device and its configuration to make a template. Then once you
1172 are happy with the template, you will want to make many clones from it.
1173 virt-sysprep
1175 |
1176 v
1177 original guest --------> template ---------->
1178 \------> cloned
1179 \-----> guests
1180 \---->
1181 You can, of course, just copy the block device on the host using cp(1)
1183 or dd(1).
1184 dd dd
1186 original guest --------> template ---------->
1187 \------> cloned
1188 \-----> guests
1189 \---->
1190 There are some smarter (and faster) ways too:
1192 snapshot
1194 template ---------->
1195 \------> cloned
1196 \-----> guests
1197 \---->
1198 You may want to run virt-sysprep twice, once to reset the guest (to
1200 make a template) and a second time to customize the guest for a
1201 specific user:
1202 virt-sysprep virt-sysprep
1204 (reset) (add user, keys, logos)
1205 | |
1206 dd v dd v
1207 original guest ----> template ---------> copied ------> custom
1208 template guest
1209 • Create a snapshot using qemu-img:
1211 qemu-img create -f qcow2 -o backing_file=original snapshot.qcow
1213 The advantage is that you don’t need to copy the original (very
1215 fast) and only changes are stored (less storage required).
1216 Note that writing to the backing file once you have created guests
1218 on top of it is not possible: you will corrupt the guests.
1219 • Create a snapshot using "lvcreate --snapshot".
1221 • Other ways to create snapshots include using filesystems-level
1223 tools (for filesystems such as btrfs).
1224 Most Network Attached Storage (NAS) devices can also create cheap
1226 snapshots from files or LUNs.
1227 • Get your NAS to duplicate the LUN. Most NAS devices can also
1229 duplicate LUNs very cheaply (they copy them on-demand in the
1230 background).
1231 • Prepare your template using virt-sparsify(1). See below.
1233 VIRT-CLONE
1235 A separate tool, virt-clone(1), can be used to duplicate the block
1236 device and/or modify the external libvirt configuration of a guest. It
1237 will reset the name, UUID and MAC address of the guest in the libvirt
1238 XML.
1239 virt-clone(1) does not use libguestfs and cannot look inside the disk
1241 image. This was the original motivation to write virt-sysprep.
1242 SPARSIFY
1244 virt-sparsify
1245 original guest --------> template
1246 virt-sparsify(1) can be used to make the cloning template smaller,
1248 making it easier to compress and/or faster to copy.
1249 Notice that since virt-sparsify also copies the image, you can use it
1251 to make the initial copy (instead of "dd").
1252 RESIZE
1254 virt-resize
1255 template ---------->
1256 \------> cloned
1257 \-----> guests
1258 \---->
1259 If you want to give people cloned guests, but let them pick the size of
1261 the guest themselves (eg. depending on how much they are prepared to
1262 pay for disk space), then instead of copying the template, you can run
1263 virt-resize(1). Virt-resize performs a copy and resize, and thus is
1264 ideal for cloning guests from a template.
1265
1267 The two options --firstboot and --script both supply shell scripts that
1268 are run against the guest. However these two options are significantly
1269 different.
1270 --firstboot script uploads the file "script" into the guest and
1272 arranges that it will run, in the guest, when the guest is next booted.
1273 (The script will only run once, at the "first boot").
1274 --script script runs the shell "script" on the host, with its current
1276 directory inside the guest filesystem.
1277 If you needed, for example, to "yum install" new packages, then you
1279 must not use --script for this, since that would (a) run the "yum"
1280 command on the host and (b) wouldn't have access to the same resources
1281 (repositories, keys, etc.) as the guest. Any command that needs to run
1282 on the guest must be run via --firstboot.
1283 On the other hand if you need to make adjustments to the guest
1285 filesystem (eg. copying in files), then --script is ideal since (a) it
1286 has access to the host filesystem and (b) you will get immediate
1287 feedback on errors.
1288 Either or both options can be used multiple times on the command line.
1290
1292 Virtual machines that employ full disk encryption internally to the
1293 guest should not be considered for cloning and distribution, as it
1294 provides multiple parties with the same internal volume key, enabling
1295 any one such party to decrypt all the other clones. Refer to the LUKS
1296 FAQ for details.
1297 Although virt-sysprep removes some sensitive information from the
1299 guest, it does not pretend to remove all of it. You should examine the
1300 "OPERATIONS" above and the guest afterwards.
1301 Sensitive files are simply removed. The data they contained may still
1303 exist on the disk, easily recovered with a hex editor or undelete tool.
1304 The --scrub option can be used to scrub files instead of just deleting
1305 them. virt-sparsify(1) is another way to remove this content. See
1306 also the scrub(1) command to get rid of deleted content in directory
1307 entries and inodes.
1308 RANDOM SEED
1310 (This section applies to Linux guests only)
1311 For supported guests, virt-sysprep writes a few bytes of randomness
1313 from the host into the guest’s random seed file.
1314 If this is just done once and the guest is cloned from the same
1316 template, then each guest will start with the same entropy, and things
1317 like SSH host keys and TCP sequence numbers may be predictable.
1318 Therefore you should arrange to add more randomness after cloning from
1320 a template too, which can be done by enabling just the customize
1321 module:
1322 cp template.img newguest.img
1324 virt-sysprep --enable customize -a newguest.img
1325
1327 For guests which make use of SELinux, special handling for them might
1328 be needed when using operations which create new files or alter
1329 existing ones.
1330 For further details, see "SELINUX" in virt-builder(1).
1332
1334 Windows 8 "fast startup" can prevent virt-sysprep from working. See
1335 "WINDOWS HIBERNATION AND WINDOWS 8 FAST STARTUP" in guestfs(3).
1336
1338 This program returns 0 on success, or 1 if there was an error.
1339
1341 "VIRT_TOOLS_DATA_DIR"
1342 This can point to the directory containing data files used for
1343 Windows firstboot installation.
1344 Normally you do not need to set this. If not set, a compiled-in
1346 default will be used (something like /usr/share/virt-tools).
1347 This directory may contain the following files:
1349 rhsrvany.exe
1351 This is the RHSrvAny Windows binary, used to install a
1352 "firstboot" script in Windows guests. It is required if you
1353 intend to use the --firstboot or --firstboot-command options
1354 with Windows guests.
1355 See also: "https://github.com/rwmjones/rhsrvany"
1357 pvvxsvc.exe
1359 This is a Windows binary shipped with SUSE VMDP, used to
1360 install a "firstboot" script in Windows guests. It is required
1361 if you intend to use the --firstboot or --firstboot-command
1362 options with Windows guests.
1363 For other environment variables, see "ENVIRONMENT VARIABLES" in
1365 guestfs(3).
1366
1368 guestfs(3), guestfish(1), virt-builder(1), virt-clone(1),
1369 virt-customize(1), virt-rescue(1), virt-resize(1), virt-sparsify(1),
1370 virsh(1), lvcreate(8), qemu-img(1), scrub(1), http://libguestfs.org/,
1371 http://libvirt.org/.
1372
1374 Richard W.M. Jones http://people.redhat.com/~rjones/
1375 Wanlong Gao, Fujitsu Ltd.
1377
1379 Copyright (C) 2011-2020 Red Hat Inc.
1380 Copyright (C) 2012 Fujitsu Ltd.
1382
1384 This program is free software; you can redistribute it and/or modify it
1385 under the terms of the GNU General Public License as published by the
1386 Free Software Foundation; either version 2 of the License, or (at your
1387 option) any later version.
1388 This program is distributed in the hope that it will be useful, but
1390 WITHOUT ANY WARRANTY; without even the implied warranty of
1391 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1392 General Public License for more details.
1393 You should have received a copy of the GNU General Public License along
1395 with this program; if not, write to the Free Software Foundation, Inc.,
1396 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
1397
1399 To get a list of bugs against libguestfs, use this link:
1400 https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
1401 To report a new bug against libguestfs, use this link:
1403 https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
1404 When reporting a bug, please supply:
1406 • The version of libguestfs.
1408 • Where you got libguestfs (eg. which Linux distro, compiled from
1410 source, etc)
1411 • Describe the bug accurately and give a way to reproduce it.
1413 • Run libguestfs-test-tool(1) and paste the complete, unedited output
1415 into the bug report.
1416guestfs-tools-1.49.7 2022-12-10 virt-sysprep(1)