1 Ganeti Cluster tools (htools)
2 =============================
4 These are some simple cluster tools for fixing common problems. Right
5 now N+1 and rebalancing are included. Starting with version 0.1.0,
6 only Ganeti 2.0 is supported.
12 This program runs a very simple brute force algorithm over the instance
13 placement space in order to determine the shortest number of replace-disks
14 needed to fix the cluster. Note this means we won't get a balanced cluster,
15 just one that passes N+1 checks.
17 For algorithm details and usage, see the man page hn1(1).
22 Compared to the N+1 solver, the rebalancer uses a very simple algorithm:
23 repeatedly try to move each instance one step, so that the cluster score
24 becomes better. We stop when no further move can improve the score.
26 For algorithm details and usage, see the man page hbal(1).
28 Integration with Ganeti
29 -----------------------
31 The programs can either get their input from text files, or online
32 from a cluster via RAPI. For online collection via RAPI, the "-m"
33 argument to both hn1 and hbal should specify the cluster or master
36 For text files, a separate tool (hscan) is provided to automate their
37 gathering if RAPI is available, which is better since it can extract
38 more precise information. In case RAPI is not usable for whatever
39 reason, the following two commands should be run::
41 gnt-node list -oname,mtotal,mnode,mfree,dtotal,dfree,offline \
42 --separator '|' --no-headers > nodes
43 gnt-instance list -oname,admin_ram,sda_size,status,pnode,snodes \
44 --separator '|' --no-head > instances
46 These two files should be saved under the names of *nodes* and *instances*.
51 If installing from source, you need a working ghc compiler (6.8 at
52 least) and some extra Haskell libraries which usually need to be
58 One these are available, just typing *make* in the top-level directory
61 Internal (implementation) documentation is available in the ``apidoc``