hscan

NAME

hscan - Scan clusters via RAPI and save node/instance data

SYNOPSIS

hscan [-p] [–no-headers] [-d path ] cluster...

hscan –version

DESCRIPTION

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 given, etc.)

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 scripting yet.

OPTIONS

The options that can be passed to the program are as follows:

-p, –print-nodes

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 htools(1).

-d path

Save the node and instance data for each cluster under path, instead of the current directory.

-V, –version

Just show the program version and exit.

EXIT STATUS

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 data).

BUGS

The program does not check its input data for consistency, and aborts with cryptic errors messages in this case.

EXAMPLE

$ 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