HOWTO: Xen tools within FreeBSD domU
====================================
Last updated: 2011-01-31
Author: Janne Snabb <snabb@epipe.com>

I wanted to look at xenstore contents from my domU. The domU does
not have access to all data but the entries related to the domU
instance itself are mostly available.

The tools are useful for debugging Xen related problems when one
does not have access to the dom0 or wants to view the entries from
domU's perspective. xen-tools-domU port is being worked on at the
time of this writing.

Here is how to get a working "xenstore-ls" command and other Xen
tools for your FreeBSD domU.


Prerequisites
-------------

For building the software you need: python, gmake

xenstore tools run depedencies: XENHVM or XEN kernel (GENERIC will not work)

xen-detect run depedencies: none (works with GENERIC also)


Building & installation
-----------------------

1. ftp http://bits.xensource.com/oss-xen/release/4.0.1/xen-4.0.1.tar.gz

2. tar xvfz xen-4.0.1.tar.gz

3. cd xen-4.0.1/tools

4. gmake -C include

5. cd misc

6. gmake xen-detect

7. install xen-detect /usr/local/bin

8. cd ../xenstore

8.5: Consider applying a patch as follows, it will make your life
easier later:
  ftp http://docs.freebsd.org/cgi/mid.cgi?034C454F-CE2B-4310-BD09-2A9989E544E9
  patch < freebsd-xen

9. Build client library and programs:
  gmake clients

10. Install client library and programs:
  install libxenstore.so.3.0 /usr/local/lib
  install xenstore xenstore-control /usr/local/bin
  cd /usr/local/bin
  ln xenstore xenstore-chmod
  ln xenstore xenstore-exists
  ln xenstore xenstore-list
  ln xenstore xenstore-ls
  ln xenstore xenstore-read
  ln xenstore xenstore-rm
  ln xenstore xenstore-write


Settings
--------

Set a required environment variable if you did not apply the patch
at step 8.5 in the previous section:

  export XENSTORED_PATH=/dev/xen/xenstore

or if you use csh/tcsh:

  setenv XENSTORED_PATH /dev/xen/xenstore


Usage
-----

Now you can do things such as:

Check if you are running under Xen and output the Xen version number
as well as the virtualization mode (HVM or PV):

  xen-detect

Output the name of your virtual machine:

  xenstore-read name

List some information about your devices:

  xenstore-ls device

List information about your first network device from the backend
side with different output format:

  xenstore-ls -f `xenstore-read device/vif/0/backend`


Best Regards,
--
Janne Snabb / EPIPE Communications
snabb@epipe.com - http://epipe.com/