-Ganeti Cluster tools (ganeti-htools)
-====================================
+Ganeti 2.8
+==========
-These are some simple cluster tools for fixing common allocation
-problems on Ganeti 2.0 clusters.
+For installation instructions, read the INSTALL and the doc/install.rst
+files.
-Note that these tools are most useful for bigger cluster sizes
-(e.g. more than five or ten machines); at lower sizes, the computations
-they do can also be done manually.
-
-Most of the tools revolve around the concept of keeping the cluster N+1
-compliant: this means that in case of failure of any node, the instances
-affected can be failed over (via ``gnt-node failover`` or ``gnt-instance
-failover``) to their secondary node, and there is enough memory reserved
-for this operation without needing to shutdown other instances or
-rebalance the cluster.
-
-**Quick start** (see the installation section for more details):
-
-- (have the ghc compiler and the prerequisite libraries installed)
-- ``make``
-- ``./hbal -m $cluster -C -p``
-- look at the original and final cluster layout, and if acceptable,
- execute the given commands
-
-
-Available tools
----------------
-
-Cluster rebalancer
-~~~~~~~~~~~~~~~~~~
-
-The rebalancer uses a simple algorithm to try to get the nodes of the
-cluster as equal as possible in their resource usage. It tries to
-repeatedly move each instance one step, so that the cluster score
-becomes better. We stop when no further move can improve the score.
-
-For algorithm details and usage, see the man page ``hbal(1)``.
-
-IAllocator plugin
-~~~~~~~~~~~~~~~~~
-
-The ``hail`` iallocator plugin can be used for allocations of mirrored
-and non-mirrored instances and for relocations of mirrored instances. It
-needs to be installed in Ganeti's iallocator search path—usually
-``/usr/lib/ganeti/iallocators`` or
-``/usr/local/lib/ganeti/iallocators``, and after that it can be used via
-ganeti's ``--iallocator`` option (in various gnt-node/gnt-instance
-commands). See the man page ``hail(1)`` for more details.
-
-Cluster capacity estimator
-~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The ``hspace`` program will, given an input instance specification,
-estimate how many instances of those type can be place on the cluster
-before it will become full (as in any new allocation would fail N+1
-checks). For more details, see the man page hspace(1).
-
-
-Integration with Ganeti
------------------------
-
-The ``hbal`` and ``hspace`` programs can either get their input from
-text files, locally from the master daemon (when run on the master node
-of a cluster), or remote from a cluster via RAPI. The "-L" argument
-enables local collection (with an optional path to the unix socket). For
-online collection via RAPI, the "-m" argument should specify the cluster
-or master node name. Only ``hbal`` and ``hspace`` use these arguments,
-``hail`` uses the standard iallocator API and thus doesn't need any
-special setup (just needs to be installed in the right directory).
-
-For generating the text files, a separate tool (``hscan``) is provided
-to automate their gathering if RAPI is available, which is better since
-it can extract more precise information. In case RAPI is not usable for
-whatever reason, ``gnt-node list`` and ``gnt-instance list`` could be
-used, and their output concatenated in a single file, separated by one
-blank line. If you need to do this manually, you'll need to check the
-sources to see which fields are needed exactly.
-
-
-The ``hail`` program gets its data automatically from Ganeti when used
-as described in its section.
-
-Installation
-------------
-
-If installing from source, you need a working ghc compiler (6.8 at
-least) and some extra Haskell libraries which usually need to be
-installed manually:
-
-- `json <http://hackage.haskell.org/package/json>`_
-- `curl <http://hackage.haskell.org/package/curl>`_
-- `network <http://hackage.haskell.org/package/network>`_
-
-Once these are installed, just typing *make* in the top-level directory
-should be enough. If you edit the documentation sources, you will need
-the ``pandoc`` program to rebuilt it.
-
-Only the ``hail`` program needs to be installed in a specific place, the
-other tools are not location-dependent.
-
-For running the (admittedly small) unittest suite (via *make check*),
-the QuickCheck version 1 library is needed.
-
-Internal (implementation) documentation is available in the ``apidoc``
-directory.
-
-.. vim: set textwidth=72 :
-.. Local Variables:
-.. mode: rst
-.. fill-column: 72
-.. End:
+For a brief introduction, read the ganeti(7) manpage and the other pages
+it suggests.
projects / ganeti-local / blobdiff