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