X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=README;h=65e22cb6b08d5138d925e3162253b21adfeea0e3;hp=f470a58e9e0c6822098c54f741c111b060112193;hb=4d900cdac8258daa2e99c6ceb2a4985154e94150;hpb=27161658c897544a58c7d4f87c08f2ee8ce08d43 diff --git a/README b/README index f470a58..65e22cb 100644 --- a/README +++ b/README @@ -13,16 +13,19 @@ 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 FTP. +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 -or Haskell). You can also use it from shell scripts or the command line. +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). -For discussion please use the fedora-virt mailing list: +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: - https://www.redhat.com/mailman/listinfo/fedora-virt + http://www.redhat.com/mailman/listinfo/libguestfs Home page @@ -34,10 +37,9 @@ Home page Requirements ---------------------------------------------------------------------- -- recent QEMU >= 0.10 with vmchannel support - http://lists.gnu.org/archive/html/qemu-devel/2009-02/msg01042.html +- recent QEMU >= 0.12 with virtio-serial support -- febootstrap >= 2.0 +- febootstrap >= 2.10 - fakeroot @@ -45,20 +47,36 @@ Requirements - XDR, rpcgen (on Linux these are provided by glibc) +- pcre (Perl Compatible Regular Expressions C library) (optional) + +- libmagic (the library that corresponds to the 'file' command) (optional) + +- libvirt (optional) + +- libxml2 (optional) + +- Augeas (http://augeas.net/) (optional) + +- gperf + - squashfs-tools (mksquashfs only) -- (Optional) Augeas (http://augeas.net/) +- genisoimage / mkisofs + +- hivex >= 1.2.1 (http://libguestfs.org/download) + +- (Optional) FUSE to build the FUSE module - perldoc (pod2man, pod2text) to generate the manual pages and other documentation. - (Optional) Readline to have nicer command-line editing in guestfish. -- (Optional) 'reged' program from chntpw to decode Windows registry - entries (http://home.eunet.no/~pnordahl/ntpasswd/) +- (Optional) xmllint to validate virt-inspector RELAX NG schema -- (Optional) OCaml if you want to rebuild the generated files, and - also to build the OCaml bindings +- (Optional) OCaml + OCaml library xml-light if you want to rebuild + the generated files, and also to build the OCaml bindings + (http://tech.motion-twin.com/xmllight.html) - (Optional) local Fedora mirror @@ -73,6 +91,15 @@ bindings - (Optional) GHC if you want to build the Haskell bindings +- (Optional) Perl XML::XPath, Sys::Virt modules (for libvirt support +in virt-inspector). + +- (Optional, but highly recommended) perl-libintl for translating perl code. + +- (Optional) po4a for translating manpages and POD files. + +- (Optional) PHP, phpize if you want to build the PHP bindings + Running ./configure will check you have all the requirements installed on your machine. @@ -120,10 +147,17 @@ or build from our source RPMs. Debian ---------------------------------------------------------------------- -libguestfs should build and run on Debian. At the moment we don't -provide Debian packages, and because of the appliance it's rather -complicated to provide a package which could be accepted into the -Debian repositories. Want to help? Please contact us. +libguestfs is now built as a package in Debian by Guido Gunther and +the other Debian libvirt maintainers. See: + +http://wiki.debian.org/Teams/DebianLibvirtTeam#Packages + +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. qemu @@ -132,16 +166,9 @@ qemu By far the most common problem is with broken or incompatible qemu releases. -First of all, you need qemu >= 0.10.4, which contains a vmchannel -implementation. There are several, conflicting, incompatible things -called 'vmchannel' which at one time or another have been added or -proposed for qemu/KVM. The _only_ one we support is this one: - - http://lists.gnu.org/archive/html/qemu-devel/2009-02/msg01042.html - -Secondly, different versions of qemu have problems booting the -appliance for different reasons. This varies between versions of -qemu, and Linux distributions which add their own patches. +Different versions of qemu have problems booting the appliance for +different reasons. This varies between versions of qemu, and Linux +distributions which add their own patches. If you find a problem, you could try using your own qemu built from source (qemu is very easy to build from source), with a 'qemu @@ -168,13 +195,93 @@ On some systems, the chmod will not survive a reboot, and you will 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 FTP export will work fine, but running commands in -guests may not be possible. +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. @@ -219,13 +326,13 @@ first: - python - rpm-python http://www.rpm.org/ - yum http://yum.baseurl.org/ - - febootstrap http://et.redhat.com/~rjones/febootstrap/ + - febootstrap http://people.redhat.com/~rjones/febootstrap/ Copyright and license information ---------------------------------------------------------------------- -Copyright (C) 2009 Red Hat Inc. +Copyright (C) 2009-2010 Red Hat Inc. The library is distributed under the LGPLv2+. The programs are distributed under the GPLv2+. Please see the files COPYING and