Small documentation update

README

-Ganeti Cluster tools (htools)
-=============================
+Ganeti Cluster tools (ganeti-htools)
+====================================
 
-These are some simple cluster tools for fixing common problems. Right
-now N+1 and rebalancing are included. Starting with version 0.1.0,
-only Ganeti 2.0 is supported.
+These are some simple cluster tools for fixing common allocation
+problems on Ganeti 2.0 clusters.
 
+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.
+
+Available tools
+---------------
 
 Cluster rebalancer
-------------------
+~~~~~~~~~~~~~~~~~~
 
-Compared to the N+1 solver, the rebalancer uses a very simple algorithm:
-repeatedly try to move each instance one step, so that the cluster score
+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.
+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``.
+``/usr/local/lib/ganeti/iallocators``. See the man page hail(1).
 
 Integration with Ganeti
 -----------------------
@@ -45,14 +52,14 @@ 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 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::
+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,admin_ram,sda_size,status,pnode,snodes \
+    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
@@ -73,3 +80,7 @@ directory should be enough.
 
 Internal (implementation) documentation is available in the ``apidoc``
 directory.
+
+.. Local Variables:
+.. mode: rst
+.. End: