-Libguestfs is a library for accessing and modifying guest disk images.
-Amongst the things this is good for: making batch configuration
-changes to guests, getting disk used/free statistics (see also:
-virt-df), migrating between virtualization systems (see also:
-virt-p2v), performing partial backups, performing partial guest
-clones, cloning guests and changing registry/UUID/hostname info, and
-much else besides.
-
-Libguestfs uses Linux kernel and qemu code, and can access any type of
-guest filesystem that Linux and qemu can, including but not limited
-to: ext2/3/4, btrfs, FAT and NTFS, LVM, many different disk partition
-schemes, qcow, qcow2, vmdk.
-
-Libguestfs provides ways to enumerate guest storage (eg. partitions,
-LVs, what filesystem is in each LV, etc.). It can also run commands
-in the context of the guest. Also you can access filesystems over
-FUSE.
-
-Libguestfs is a library that can be linked with C and C++ management
-programs (or management programs written in OCaml, Perl, Python, Ruby,
-Java, PHP, Haskell or C#). You can also use it from shell scripts or the
-command line.
-
-Libguestfs was written by Richard W.M. Jones (rjones@redhat.com) and
-hacked on by lots of other people. For discussion, development,
-patches, etc. please use the mailing list:
+Libguestfs is tools and a library for accessing and modifying guest
+disk images. For more information see the home page:
+
+ http://libguestfs.org/
+
+For discussion, development, patches, etc. please use the mailing
+list:
http://www.redhat.com/mailman/listinfo/libguestfs
-Home page
+Requirements
----------------------------------------------------------------------
- http://libguestfs.org/
+Running ./configure will check you have all the requirements installed
+on your machine.
+Fedora/RHEL users:
-Requirements
-----------------------------------------------------------------------
+ A useful tip is to run:
+
+ yum-builddep libguestfs
+
+ which will install all build dependencies automatically. If that is
+ successful, you don't need to bother with the rest of this section.
+
+Debian/Ubuntu users:
+
+ Take a look at the debian/control file and install everything listed
+ in "Build-Depends". If that is successful, you don't need to bother
+ with the rest of this section.
+
+The full requirements are described below.
+
+For basic functionality and the C tools:
+
+- look at appliance/packagelist.in and install as many of the packages
+ that apply to your distro as possible
-- recent QEMU >= 0.12 with virtio-serial support
+- recent QEMU >= 0.13 (0.14 or later is better) with virtio-serial support
-- febootstrap >= 2.10
+- kernel >= 2.6.34 with virtio-serial support enabled.
-- fakeroot
+- virtio-block and virtio-net drivers should be compiled into your
+ host kernel (strictly speaking this is optional, but you will have
+ to make complex changes to the ./configure command line to get it
+ to work if you don't have virtio)
-- fakechroot >= 2.9
+- febootstrap >= 3.3 (it is best to use the latest version)
+
+ Notes: (1) febootstrap 2.x WILL NOT WORK
+ (2) febootstrap 3.x is distro-independent, and is required on
+ Debian and other distros as well as Fedora
- XDR, rpcgen (on Linux these are provided by glibc)
-- pcre (Perl Compatible Regular Expressions C library) (optional)
+- cpio
+
+- gperf
+
+- pcre (Perl Compatible Regular Expressions C library)
+
+- genisoimage (NOT mkisofs any more)
+
+- hivex >= 1.2.7 (http://libguestfs.org/download) (optional)
- libmagic (the library that corresponds to the 'file' command) (optional)
- libxml2 (optional)
-- Augeas (http://augeas.net/) (optional)
+- libconfig (optional)
-- gperf
+- augeas >= 0.5.0 (http://augeas.net/) (optional)
-- squashfs-tools (mksquashfs only)
+- Berkeley DB 'db_dump' and 'db_load' utilities
+ (db4-utils or db4.X-util or similar) (optional)
-- genisoimage / mkisofs
+- perldoc (pod2man, pod2text, pod2html) to generate the manual pages
+ and other documentation.
-- hivex >= 1.2.1 (http://libguestfs.org/download)
+- Readline to have nicer command-line editing in guestfish (optional)
-- (Optional) Berkeley DB 'db_dump' and 'db_load' utilities
- (db4-utils or db4.X-util or similar)
+- xmllint (part of libxml2) to validate virt-inspector
+ RELAX NG schema (optional)
-- (Optional) FUSE to build the FUSE module
+- OCaml if you want to rebuild the generated files, and
+ also to build the OCaml bindings (optional)
-- perldoc (pod2man, pod2text) to generate the manual pages and
- other documentation.
+- po4a for translating manpages and POD files.
+ This is optional when compiling from the tarball, but mandatory
+ if you compile from git.
-- (Optional) Readline to have nicer command-line editing in guestfish.
+- getfacl, getfattr libraries and programs (optional)
-- (Optional) xmllint to validate virt-inspector RELAX NG schema
+To build FUSE support (guestmount):
-- (Optional) OCaml if you want to rebuild the generated files, and
- also to build the OCaml bindings
+- FUSE libraries and kernel module (optional)
-- (Optional) local Fedora mirror
+To build virt-resize:
-- (Optional) Perl if you want to build the perl bindings
+- OCaml PCRE bindings (ocaml-pcre) (optional)
-- (Optional) Python if you want to build the python bindings
+To build language bindings:
-- (Optional) Ruby, rake if you want to build the ruby bindings
+- Perl if you want to build the perl bindings (optional)
-- (Optional) Java, JNI, jpackage-utils if you want to build the java
-bindings
+- Python if you want to build the python bindings (optional)
-- (Optional) GHC if you want to build the Haskell bindings
+- Ruby, rake if you want to build the ruby bindings (optional)
-- (Optional) Perl Sys::Virt module.
+- Java, JNI, jpackage-utils if you want to build the java
+ bindings (optional)
-- (Optional) Perl Win::Hivex module.
+- GHC if you want to build the Haskell bindings (optional)
-- (Optional) Perl Pod::Usage module.
+- PHP, phpize if you want to build the PHP bindings (optional)
-- (Optional) Perl Test::More module (from perl Test::Simple).
+To build the Perl tools:
-- (Optional) Perl String::ShellQuote module.
+- Perl Sys::Virt module (optional)
-- (Optional, but highly recommended) perl-libintl for translating perl code.
+- Perl Win::Hivex module (optional)
-- (Optional) po4a for translating manpages and POD files.
+- Perl Pod::Usage module (optional)
-- (Optional) PHP, phpize if you want to build the PHP bindings
+- Perl Test::More module (from perl Test::Simple) (optional)
-Running ./configure will check you have all the requirements installed
-on your machine.
+- Perl String::ShellQuote module (optional)
+
+- perl-libintl for translating perl code (optional)
Building
Then make the daemon, library and root filesystem:
- ./configure [--with-mirror=URI]
+ ./configure
make
-Use the optional --with-mirror parameter to specify the URI of a local
-Fedora mirror. See the discussion of the MIRROR parameter in the
-febootstrap(8) manpage.
-
Finally run the tests:
make check
make install
+You can run guestfish, guestmount and the virt tools without needing
+to install, using the "run" script in the top directory. This script
+sets up some environment variables. For example:
-Fedora
-----------------------------------------------------------------------
+ ./run ./fish/guestfish [usual guestfish args ...]
-We provide packages for Fedora >= 11 in Fedora. Use those, or build
-from our source RPMs - it's far simpler that way.
+ ./run ./inspector/virt-inspector [usual virt-inspector args ...]
-You can compile libguestfs on Fedora 10 but you cannot use it with the
-version of qemu in Fedora 10. You need to compile your own qemu, see
-section 'qemu' below.
+If you are already in the fish/ subdirectory, then the following
+command will also work:
+ ../run ./guestfish [...]
-RHEL / EPEL / CentOS etc
-----------------------------------------------------------------------
-
-We provide packages in EPEL which cover RHEL/CentOS >= 5. Use those
-or build from our source RPMs.
+You can also make a symlink (note: NOT a hard link) from your $PATH to
+the run script, eg:
+ cd ~/bin
+ ln -s ~/libguestfs/run libguestfs-run
+ cd ~/libguestfs
+ libguestfs-run ./inspector/virt-inspector [...]
-Debian
-----------------------------------------------------------------------
+You can also run the C programs under valgrind like this:
-libguestfs is now built as a package in Debian by Guido Gunther and
-the other Debian libvirt maintainers. See:
+ ./run valgrind [valgrind opts...] ./cat/virt-cat [virt-cat opts...]
-http://wiki.debian.org/Teams/DebianLibvirtTeam#Packages
+This also works with sudo (eg. if you need root access for libvirt or
+to access a block device):
-You can build for Debian in two different ways, either building a
-Fedora-based appliance using febootstrap, yum, rpm, fakeroot,
-fakechroot (all packaged in Debian). However the recommended way is
-to build a Debian-based appliance using debootstrap and debirf.
-
-Both ways are supported by the configure script.
+ sudo ./run ./cat/virt-cat -d LinuxGuest /etc/passwd
qemu
need to make edits to the udev configuration.
-vmchannel
-----------------------------------------------------------------------
-
-Previous versions of libguestfs required something called "vmchannel".
-Vmchannel is a special device given to virtual machines which allows
-them to communicate in some way with the host, often (but not always)
-without using a traditional network device. In reality, there is no
-one thing called "vmchannel". This idea has been reimplemented
-several times under the name vmchannel, and other hypervisors have
-their own incompatible implementation(s) too.
-
-In libguestfs <= 1.0.71, we required a specific vmchannel which is
-properly known as "guestfwd" and has been upstream in qemu since here:
-
- http://lists.gnu.org/archive/html/qemu-devel/2009-02/msg01042.html
-
-In libguestfs >= 1.0.71 we don't require any vmchannel implementation,
-as long as qemu has been compiled with support for SLIRP (user mode
-networking, or "-net user"), which is almost always the case.
-
-In libguestfs >= 1.5.4 we switched again to using qemu's virtio-serial
-and removed all the other vmchannels and the SLIRP channel.
-
-
-Supermin appliance
-----------------------------------------------------------------------
-
-If you configure with --enable-supermin then we will build a supermin
-appliance (supermin = super-minimized). This is a very specialized
-appliance which is built on-the-fly at runtime (specifically, when you
-call guestfs_launch).
-
-The normal appliance is a self-contained Linux operating system, based
-on the Fedora/RHEL/CentOS Linux distro. So it contains a complete
-copy of all the libraries and programs needed, like kernel, libc,
-bash, coreutils etc etc.
-
-The supermin appliance removes the kernel and all the executable
-libraries and programs from the appliance. That just leaves a
-skeleton of config files and some data files, which is obviously
-massively smaller than the normal appliance. At runtime we rebuild
-the appliance on-the-fly from the libraries and programs on the host
-(eg. pulling in the real /lib/libc.so, the real /bin/bash etc.)
-
-Although this process of rebuilding the appliance each time sounds
-slow, it turns out to be faster than using the prebuilt appliance.
-(Most of the saving comes from not compressing the appliance - it
-transpires that decompressing the appliance is the slowest part of the
-whole boot sequence). On my machine, a new appliance can be built in
-under a fifth of a second, and the boot time is several seconds
-shorter.
-
-The big advantage of the supermin appliance for distributions like
-Fedora is that it gets security fixes automatically from the host, so
-there is no need to rebuild the whole of libguestfs for a security
-update in some underlying library.
-
-There are several DISADVANTAGES:
-
-It won't work at all except in very narrow, controlled cases like the
-Fedora packaging case. We control the dependencies of the libguestfs
-RPM tightly to ensure that the required binaries are actually present
-on the host.
-
-Furthermore there are certain unlikely changes in the packages on the
-host which could break a supermin appliance, eg. an updated library
-which depends on an additional data file.
-
-Also supermin appliances are subjected to changes in the host kernel
-which might break compatibility with qemu -- these are, of course,
-real bugs in any case.
-
-Lastly, supermin appliances really can't be moved between branches of
-distributions (eg. built on Fedora 12 and moved to Fedora 10) because
-they are not self-contained and they rely on certain libraries being
-around. You shouldn't do this anyway.
-
-Use supermin appliances with caution.
-
-
-Notes on cross-architecture support
-----------------------------------------------------------------------
-
-At the moment we basically don't support cross-architecture or
-32-on-64. This limits what is possible for some guests. Filesystem
-operations and FUSE will work fine, but running commands in guests may
-not be possible.
-
-To enable this requires work for cross-architecture and 32-on-64
-support in febootstrap, fakeroot and fakechroot.
-
-The daemon/ directory contains its own configure script. This is so
-that in future we will be able to cross-compile the daemon.
-
-
Mirroring tip
----------------------------------------------------------------------
On my machines I can usually rebuild the appliance in around 3
-minutes. If it takes much longer for you, use a local Fedora mirror
+minutes. If it takes much longer for you, use a local distro mirror
or squid.
To use squid to cache yum downloads, read this first:
patches if they aren't too invasive.
The main porting issues are with the dependencies needed to build the
-appliance. You will need to find or port the following packages
-first:
-
- - fakeroot
- - fakechroot
- - python
- - rpm-python http://www.rpm.org/
- - yum http://yum.baseurl.org/
- - febootstrap http://people.redhat.com/~rjones/febootstrap/
+appliance. You will need to port the febootstrap first
+(http://people.redhat.com/~rjones/febootstrap/).
Copyright and license information
----------------------------------------------------------------------
-Copyright (C) 2009-2010 Red Hat Inc.
+Copyright (C) 2009-2011 Red Hat Inc.
The library is distributed under the LGPLv2+. The programs are
distributed under the GPLv2+. Please see the files COPYING and
git.annexia.org / libguestfs.git / blobdiff