SYNOPSIS

hobbitd_channel --channel=status hobbitd_rrd [options]
hobbitd_channel --channel=data hobbitd_rrd [options]

DESCRIPTION

hobbitd_rrd is a worker module for hobbitd, and as such it is normally run via the hobbitd_channel(8) program. It receives "status" and "data" messages from hobbitd via stdin, and updates the RRD databases used to generate trend-graphs.

Clients can send data to Xymon using both status- and data- messages. So you will normally run two instances of this module, once for the "status" channel and once for the "data" channel.

hobbitd_rrd understands data sent by the LARRD 0.43c client-side scripts (the so-called "bottom-feeder" scripts). So you still want to install the LARRD bottom-feeders on the clients you monitor.

Note: For certain types of data, the RRD files used by Xymon are imcompatible with those generated by the Big Brother LARRD add-on. See the COMPATIBILITY section below.

OPTIONS

--debug

Enable debugging output.

--rrddir=DIRECTORY

Defines the directory where the RRD-files are stored. hobbitd_rrd will use the location pointed to by the BBRRDS environment if this option is not present.

--extra-script=FILENAME

Defines the script that is run to get the RRD data for tests that are not built into hobbitd_rrd. You must also specify which tests are handled by the external script in the --extra-tests option. This option can only be given once, so the script must handle all of the external test-data. See the CUSTOM RRD DATA section below. Note that this is NOT needed if your custom graphs are generated by the NCV (Name Colon Value) module described below, it is only required for data where you have a custom script to parse the status message and extract the data that is put into the graph.

--extra-tests=TEST[,TEST]

List of testnames that are handled by the external script. See the CUSTOM RRD DATA section below. Note that NCV graphs should NOT be listed here, but in the TEST2RRD environment variable - see below.

COLLECTED DATA

The following RRD-file datasets are generated by hobbitd_rrd:

la

Records the CPU load average. Data is collected from the "cpu" status report. Requires that a Xymon client is running on the monitored server.

disk

Records the disk utilization. Data is collected from the "disk" status report. Requires that a Xymon-compatible client is running on the monitored server.

memory

Records memory- and swap-utilization. Data is collected from the "memory" status report. If no "memory" status is reported, it will use the data from the Win32 client "cpu" status report to generate this dataset. Requires that a Xymon-compatible client is running on the monitored server.

netstat

Records TCP and UDP statistics. Data is collected from the "netstat" status report; however, this data is often sent via the Xymon "data" protocol, so there need not be a "netstat" column visible on the Xymon display. To get these data, the LARRD netstat bottom-feeder script must be running on the monitored server.

vmstat

Records system performance metrics from the "vmstat" command. Data is collected from the "vmstat" status report; however, this data is often sent via the Xymon "data" protocol, so there need not be a "vmstat" column visible on the Xymon display. To get these data, the LARRD vmstat bottom-feeder script must be running on the monitored server.

tcp

Response-time metrics from all of the Xymon network tests are recorded in the "tcp" RRD.

apache

Apache server performance metrics, taken from the "apache" data report. See the description of the apache keyword in bb-hosts(5) for details.

sendmail

Sendmail server performance metrics, taken from the "mailstats" output. To get these data, the LARRD sendmail bottom-feeder script must be running on the monitored server.

mailq

Mail queue size. To get these data, the LARRD nmailq bottom-feeder script must be running on the monitored server.

bea

BEA Weblogic performance data. This is an experimental set of data collected from BEA Weblogic servers via SNMP, by the "beastats" tool included with Xymon.

iishealth

IIS webserver performance data, collected by the "iishealth" script. This script is a client-side add-on available from the www.deadcat.net archive.

temperature

Temperature data, collected with the temperature script from www.deadcat.net. To get these data, the temperature script must be running on the monitored server.

ntpstat

Tracks the deviation between the local system time and an NTP server, using the output from the "ntpq -c rv" command. A simple script to collect these data is included in the Xymon contrib/ directory.

citrix

Tracks the number of active sessions on a Citrix server using the "query session" command. An extension for the BBNT client that generates data for this graph is in the Xymon contrib/ directory.

CUSTOM RRD DATA IN NAME-COLON-VALUE (NCV) FORMAT

Many data-collection scripts report data in the form "NAME : value" or "NAME = value". So a generic module in hobbitd_rrd allows for easy tracking of this type of data.

The "ncv" module will automatically detect all occurrences of a "NAME : value" or "NAME = value" string in a status message, and generate an RRD file holding all of the name/value data found in the message (unless you use SPLITNCV, see above). The colon- or equal-sign must be present - if there is only whitespace, this module will fail.

Only the valid letters (A-Z, a-z) and digits (0-9) are used in the dataset names; whitespace and other characters are stripped off automatically. Only the first 19 characters of a dataset name are used (this is an RRD limitation). Underscore '_' is not allowed, even though RRDtool permits this, and will be stripped from the name.

When using the alternative SPLITNCV_testname, the dataset name is not limited in length, and non-valid characters are changed to underscores instead of being stripped off. The dataset inside the resulting rrd file is always "lambda".

Note that each "NAME : value" must be on a line by itself. If you have a custom script generating the status- or data-message that is fed into the NCV handler, make sure it inserts a newline before each of the data-items you want to track.

To enable the ncv module for a status, add a "COLUMNNAME=ncv" to the TEST2RRD setting and the COLUMNNAME to the GRAPHS setting in hobbitserver.cfg(5) , then restart Xymon. Xymon will now send all status-messages for the column COLUMNNAME through the hobbitd_rrd ncv-handler.

The name of the RRD file will be COLUMNNAME.rrd. When using SPLITNCV, the name of the RRD file will be COLUMNAME,DATASETNAME.rrd.

By default, all of the datasets are generated as the RRD type "DERIVE" which works for all types of monotonically increasing counters. If you have data that are of the type GAUGE, you can override the default via an environment variable NCV_COLUMNNAME (or SPLITNCV_COLUMNAME).

E.g. if you are using the bb-mysqlstatus script from www.deadcat.net to collect data about your MySQL server, it generates a report in the column called "mysql". One data item is the average number of queries/second, which must be logged in the RRD file as type "GAUGE". To do that, add the following to hobbitserver.cfg:

    NCV_mysql="Queriespersecondavg:GAUGE" 
If you have multiple datasets that you myst define, add them to the environment variable separated by commas, e.g.

    NCV_mysql="Uptime:NONE,Queriespersecondavg:GAUGE" 

The dataset type "NONE" used above causes hobbitd_rrd to ignore this data, it is not included in the RRD file.

You can use "*" as the dataset name to match all datasets not listed. E.g.

    NCV_weather="Rain:DERIVE,*:GAUGE"
will cause the "Rainfall" dataset to be of type DERIVE, and all others of type GAUGE. If you want to track only a few of the variables in your data, you can use "*:NONE" to drop any dataset not explicitly listed.

For a more detailed "how to" description, see the on-line HTML documentation of "How to create graph custom data" available in the Help menu section on your Xymon server.

CUSTOM RRD DATA VIA SCRIPTS

hobbitd_rrd provides a simple mechanism for adding custom graphs to the set of data collected on your Xymon server. By adding the "--extra-script" and "--extra-tests" options, data reported to Xymon from selected tests are passed to an external script, which can define the RRD data-sets to store in an RRD file.

NOTE: For performance reasons, you should not use this mechanism for large amounts of data. The overhead involved in storing the received message to disk and launching the script is significantly larger than the normal hobbitd_rrd overhead. So if you have a large number of reports for a given test, you should consider implementing it in C and including it in the hobbitd_rrd tool.

Apart from writing the script, You must also add a section to hobbitgraph.cfg(5) so that hobbitgraph.cgi(1) knows how to generate the graph from the data stored in the RRD file. To make the graphs actually show up on the status-page and/or the "trends" page, add the name of the new graph to the TEST2RRD and/or GRAPHS setting in hobbitserver.cfg(5).

The script is invoked for each message that arrives, where the test-name matches one of the testnames given in the "--extra-tests" option. The script receives three commandline parameters:

Hostname

The name of the host reporting the data.

Testname

The name of the test being reported.

Filename

File containing the data that was reported. This file is generated for you by hobbitd_rrd, and is also deleted automatically after your script is finished with it.

The script must process the data that is reported, and generate the following output:

RRD data-set definitions

For each dataset that the RRD file holds, a line beginning with "DS:" must be output. If multiple data-sets are used, print one line for each dataset.
Data-set definitions are described in the rrdcreate(1) documentation, but a common definition for e.g. tracking the number of users logged on would be "DS:users:GAUGE:600:0:U". "users" is the name of the dataset, "GAUGE" is the datatype, "600" is the longest time allowed between updates for the data to be valid, "0" is the minimum value, and "U" is the maximum value (a "U" means "unknown").

RRD filename

The name of the RRD file where the data is stored. Note that Xymon stores all RRD files in host-specific directories, so unlike LARRD you should not include the hostname in the name of the RRD file.

RRD values

One line, with all of the data values collected by the script. Data-items are colon-delimited and must appear in the same sequence as your data-set definitions, e.g. if your RRD has two datasets with the values "5" and "0.4" respectively, then the script must output "5:0.4" as the RRD values.
In some cases it may be useful to define a dataset even though you will not always have data for it. In that case, use "U" (unknown) for the value.

If you want to store the data in multiple RRD files, the script can just print out more sequences of data-set definitions, RRD filenames and RRD values. If the data-set definitions are identical to the previous definition, you need not print the data-set definitions again - just print a new RRD filename and value.

The following sample script for tracking weather data shows how to use this mechanism. It assumes the status message include lines like these:

green Weather in Copenhagen is FAIR
Temperature: 21 degrees Celsius
Wind: 4 m/s
Humidity: 72 %
Rainfall: 5 mm since 6:00 AM

A shell-script to track all of these variables could be written like this:

#!/bin/sh
# Input parameters: Hostname, testname (column), and messagefile
HOSTNAME="$1"
TESTNAME="$2"
FNAME="$3"
if [ "$TESTNAME" = "weather" ]
then
        # Analyze the message we got
        TEMP=`grep "^Temperature:" $FNAME | awk '{print $2}'`
        WIND=`grep "^Wind:" $FNAME | awk '{print $2}'`
        HMTY=`grep "^Humidity:" $FNAME | awk '{print $2}'`
        RAIN=`grep "^Rainfall:" $FNAME | awk '{print $2}'`
        # The RRD dataset definitions
        echo "DS:temperature:GAUGE:600:-30:50"
        echo "DS:wind:GAUGE:600:0:U"
        echo "DS:humidity:GAUGE:600:0:100"
        echo "DS:rainfall:DERIVE:600:0:100"
        # The filename
        echo "weather.rrd"
        # The data
        echo "$TEMP:$WIND:$HMTY:$RAIN"
fi
exit 0

COMPATIBILITY

Some of the RRD files generated by hobbitd_rrd are incompatible with the files generated by the Big Brother LARRD add-on:

vmstat

The vmstat files with data from Linux based systems are incompatible due to the addition of a number of new data-items that LARRD 0.43 do not collect, but hobbitd_rrd does. This is due to changes in the output from the Linux vmstat command, and changes in the way e.g. system load metrics are reported.

netstat

All netstat files from LARRD 0.43 are incompatible with hobbitd_rrd. The netstat data collected by LARRD is quite confusing: For some types of systems LARRD collects packet-counts, for others it collects byte- counts. hobbitd_rrd uses a different RRD file-format with separate counters for packets and bytes and tracks whatever data the system is reporting.