-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.
-
-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).
-
-Cluster N+1 solver
-~~~~~~~~~~~~~~~~~~
-
-This program runs a very simple brute force algorithm over the instance
-placement space in order to determine the shortest number of replace-disks
-needed to fix the cluster. Note this means we won't get a balanced cluster,
-just one that passes N+1 checks.
-
-For algorithm details and usage, see the man page hn1(1).
-
-.. note:: This program is deprecated, hbal should be used instead.
-
-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``. See the man page hail(1).
-
-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 ``hn1`` programs can either get their input from text
-files, or online from a cluster via RAPI. For online collection via
-RAPI, the "-m" argument to both hn1 and hbal should specify the
-cluster or master node name. ``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, the following two commands should be run::
-
- gnt-node list -oname,mtotal,mnode,mfree,dtotal,dfree,offline \
- --separator '|' --no-headers > nodes
- gnt-instance list -oname,be/memory,sda_size,status,pnode,snodes \
- --separator '|' --no-head > instances
-
-These two files should be saved under the names of *nodes* and
-*instances*.
-
-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
-- curl
-
-Once these are available, just typing *make* in the top-level
-directory should be enough.
-
-Internal (implementation) documentation is available in the ``apidoc``
-directory.
-
-.. Local Variables:
-.. mode: rst
-.. End:
+For a brief introduction, read the ganeti(7) manpage and the other pages
+it suggests.
projects / ganeti-local / blobdiff