rapi: Allow auto-promotion on node role change

[ganeti-local] / INSTALL

diff --git a/INSTALL b/INSTALL
index dac5ab5..cb56e80 100644 (file)
--- a/INSTALL
+++ b/INSTALL
@@ -24,16 +24,19 @@ Before installing, please verify that you have the following programs:
 - `bridge utilities <http://www.linuxfoundation.org/en/Net:Bridge>`_
 - `iproute2 <http://www.linuxfoundation.org/en/Net:Iproute2>`_
 - `arping <http://www.skbuff.net/iputils/>`_ (part of iputils)
+- `ndisc6 <http://www.remlab.net/ndisc6/>`_ (if using IPv6)
 - `Python <http://www.python.org/>`_, version 2.4 or above, not 3.0
 - `Python OpenSSL bindings <http://pyopenssl.sourceforge.net/>`_
 - `simplejson Python module <http://code.google.com/p/simplejson/>`_
-- `pyparsing Python module <http://pyparsing.wikispaces.com/>`_
+- `pyparsing Python module <http://pyparsing.wikispaces.com/>`_, version
+  1.4.6 or above
 - `pyinotify Python module <http://trac.dbzteam.org/pyinotify/>`_
 - `PycURL Python module <http://pycurl.sourceforge.net/>`_
 - `ctypes Python module
   <http://starship.python.net/crew/theller/ctypes/>`_, if running on
   python 2.4 (optional, used for node daemon memory locking)
-- `socat <http://www.dest-unreach.org/socat/>`_
+- `socat <http://www.dest-unreach.org/socat/>`_, see :ref:`note
+  <socat-note>` below
 - `Paramiko <http://www.lag.net/paramiko/>`_, if you want automated SSH
   setup; optional otherwise but manual setup of the nodes required
 
@@ -44,13 +47,70 @@ Debian/Ubuntu, you can use this command line to install all required
 packages, except for DRBD and Xen::
 
   $ apt-get install lvm2 ssh bridge-utils iproute iputils-arping \
-                    python python-pyopenssl openssl python-pyparsing \
-                    python-simplejson python-pyinotify python-pycurl \
-                    socat
+                    ndisc6 python python-pyopenssl openssl \
+                    python-pyparsing python-simplejson \
+                    python-pyinotify python-pycurl socat
+
+If you want to also enable the `htools` components, which is recommended
+on bigger deployments (they give you automatic instance placement,
+cluster balancing, etc.), then you need to have a Haskell compiler
+installed. More specifically:
+
+- `GHC <http://www.haskell.org/ghc/>`_ version 6.10 or higher
+- or even better, `The Haskell Platform
+  <http://hackage.haskell.org/platform/>`_ which gives you a simple way
+  to bootstrap Haskell
+- `json <http://hackage.haskell.org/package/json>`_, a JSON library
+- `network <http://hackage.haskell.org/package/network>`_, a basic
+  network library
+- `parallel <http://hackage.haskell.org/package/parallel>`_, a parallel
+  programming library (note: tested with up to version 3.x)
+- `curl <http://hackage.haskell.org/package/curl>`_, bindings for the
+  curl library, only needed if you want these tools to connect to remote
+  clusters (as opposed to the local one)
+
+All of these are also available as package in Debian/Ubuntu::
+
+  $ apt-get install ghc6 libghc6-json-dev libghc6-network-dev \
+                    libghc6-parallel-dev libghc6-curl-dev
+
+Note that more recent version have switched to GHC 7.x and the packages
+were renamed::
+
+  $ apt-get install ghc libghc-json-dev libghc-network-dev \
+                    libghc-parallel-dev libghc-curl-dev
+
+The compilation of the htools components is automatically enabled when
+the compiler and the requisite libraries are found. You can use the
+``--enable-htools`` configure flag to force the selection (at which
+point ``./configure`` will fail if it doesn't find the prerequisites).
 
 If you want to build from source, please see doc/devnotes.rst for more
 dependencies.
 
+.. _socat-note:
+.. note::
+  Ganeti's import/export functionality uses ``socat`` with OpenSSL for
+  transferring data between nodes. By default, OpenSSL 0.9.8 and above
+  employ transparent compression of all data using zlib if supported by
+  both sides of a connection. In cases where a lot of data is
+  transferred, this can lead to an increased CPU usage. Additionally,
+  Ganeti already compresses all data using ``gzip`` where it makes sense
+  (for inter-cluster instance moves).
+
+  To remedey this situation, patches implementing a new ``socat`` option
+  for disabling OpenSSL compression have been contributed and will
+  likely be included in the next feature release. Until then, users or
+  distributions need to apply the patches on their own.
+
+  Ganeti will use the option if it's detected by the ``configure``
+  script; auto-detection can be disabled by explicitely passing
+  ``--enable-socat-compress`` (use the option to disable compression) or
+  ``--disable-socat-compress`` (don't use the option).
+
+  The patches and more information can be found on
+  http://www.dest-unreach.org/socat/contrib/socat-opensslcompress.html.
+
 
 Installation of the software
 ----------------------------