hscan - Scan clusters via RAPI and save node/instance data
hscan [-p] [--no-headers] [-d path] cluster...
hscan is a tool for scanning clusters via RAPI and saving their data in
the input format used by hbal(1) and hspace(1). It will also show a
one‐line score for each cluster scanned or, if desired, the cluster
state as show by the -p option to the other tools.
For each cluster, one file named cluster.data will be generated holding
the node and instance data. This file can then be used in hbal(1) or
hspace(1) via the -t option. In case the cluster name contains slashes
(as it can happen when the cluster is a fully-specified URL), these
will be replaced with underscores.
The one‐line output for each cluster will show the following:
Name The name of the cluster (or the IP address that was
Nodes The number of nodes in the cluster
Inst The number of instances in the cluster
BNode The number of nodes failing N+1
BInst The number of instances living on N+1‐failed nodes
t_mem Total memory in the cluster
f_mem Free memory in the cluster
t_disk Total disk in the cluster
f_disk Free disk space in the cluster
Score The score of the cluster, as would be reported by hbal(1)
if run on the generated data files.
In case of errors while collecting data, all fields after the name of
the cluster are replaced with the error display.
Note: this output format is not yet final so it should not be used for
The options that can be passed to the program are as follows:
Prints the node status for each cluster after the cluster’s
one‐line status display, in a format designed to allow the user
to understand the node’s most important parameters. For details,
see the man page for hbal(1).
Save the node and instance data for each cluster under path,
instead of the current directory.
Just show the program version and exit.
The exist status of the command will be zero, unless for some reason
loading the input data failed fatally (e.g. wrong node or instance
The program does not check its input data for consistency, and aborts
with cryptic errors messages in this case.
$ hscan cluster1
Name Nodes Inst BNode BInst t_mem f_mem t_disk f_disk Score
cluster1 2 2 0 0 1008 652 255 253 0.24404762
$ ls -l cluster1.data
-rw-r--r-- 1 root root 364 2009-03-23 07:26 cluster1.data
hbal(1), hspace(1), hail(1), ganeti(7), gnt-instance(8), gnt-node(8)
Copyright (C) 2009 Google Inc. Permission is granted to copy,
distribute and/or modify under the terms of the GNU General Public
License as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
On Debian systems, the complete text of the GNU General Public License
can be found in /usr/share/common-licenses/GPL.