[Libguestfs] [PATCH 10/10] Update documentation of qemu / vmchannel.

From: Richard Jones <rjones(a)trick.home.annexia.org&gt; --- README | 39 +++++++++++++++++++++++++++++---------- 1 files changed, 29 insertions(+), 10 deletions(-) diff --git a/README b/README index c6d2faa..9ba99ba 100644 --- a/README +++ b/README @@ -147,16 +147,9 @@ 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 @@ -183,6 +176,32 @@ 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. + +However we still offer the ability to use vmchannel, and in future we +may add support for other types of qemu, which is useful in a few +cases, specifically where qemu packagers decide to compile out support +for SLIRP (qemu packagers: please don't do this). + + Supermin appliance ---------------------------------------------------------------------- -- 1.6.2.5