Ubuntu Manpage: xymond_rrd - xymond worker module for updating Xymon RRD files

NAME

       xymond_rrd - xymond worker module for updating Xymon RRD files

SYNOPSIS

       xymond_channel --channel=status xymond_rrd [options]
       xymond_channel --channel=data xymond_rrd [options]

DESCRIPTION

       xymond_rrd  is  a  worker  module  for  xymond,  and as such it is normally run via the xymond_channel(8)
       program. It receives "status" and "data" messages from xymond 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.

       xymond_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. xymond_rrd will use the location pointed to
by the XYMONRRDS environment if this option is not present.

--no-cache
xymond_rrd by default caches updates to the RRD files, to reduce the disk I/O needed for storing
the RRD data. Data is collected for a 30 minute period before being committed to disk in one
update. This option disables caching of the data, so that data is stored on disk immediately.

--processor=FILENAME
xymond_rrd can send a parallel copy of all RRD updates to a single external process as a stream on
its STDIN. The data will be in a format similar to that used by rrdupdate(1): <rrdtemplate>
ts:<rrdvalue(s)> host <rrdparameters>

If the process exits, xymond_rrd will re-launch it.

--extra-script=FILENAME
Defines the script that is run to get the RRD data for tests that are not built into xymond_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.

--no-rrd
Disable the actual writing of RRD files. This is only really useful if you send all of the data
destined for the RRD files to an external processor (the --extra-script or --processor options).

ENVIRONMENT

       TEST2RRD
              Defines  the  mapping  between  a status-log columnname and the corresponding RRD database format.
              This is normally defined in the xymonserver.cfg(5) file.

       XYMONRRDS
              Default directory where RRD files are stored.

       NCV_testname
              Defines the types of data collected by the  "ncv"  module  in  xymond_rrd.   See  below  for  more
              information.

       SPLITNCV_testname
              The same as NCV_testname, but keeps the data into separate files. That is, it creates one rrd file
              per  "NAME  :  value" line found in the status message. It is useful when the list of NCV lines is
              varying.

       TRACKMAX
              Comma-separated list of columnname for which you want to keep the maximum values  along  with  the
              default average values. This only works
               for the NCV backend.

COLLECTED DATA

The following RRD-file datasets are generated by xymond_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 hosts.cfg(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 xymond_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.

Any lines in the status message prepended with a "" will be skipped by the module. This
can be used to prevent unneeded RRD files from an existing dataset from being created.

A line prepended with a "" will be ignored, along with all subsequent lines until a
line starting with "" is found, at which point processing will resume. This can be
used to ignore explanatory or other text with a mostly-ncv message.

"" can be used to ignore certain text at the beginning of a line, up until a closing
'</-->' tag on the same line, at which point the line will continue to be processed as usual. Wrapping is
not supported; but skipstart/skipend can be used to handle multiple lines.

A bare "" on its own line will stop further NCV processing of that message.

All of these ncv_ terms are case-sensitive. Note that if you have full control over your NCV output, it
is most efficient to have NCV data near the top of your message and use "" once your data
is complete.

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

SENDING METRIC DATA TO AN ADDITIONAL PROCESS

       xymond_rrd provides a mechanism to send a copy of isolated metric data to a single external processor for
       further  processing.  This  can  be  used  to  inject metric data that xymond_rrd has prepared into other
       storage systems, such as OpenTSDB, graphite, etc. The data is printed in a  format  nearly  suitable  for
       injection  using rrdupdate(1) and easily transformable to other formats. If the process exits, xymond_rrd
       will re-launch it automatically.

CUSTOM RRD DATA VIA SCRIPTS

xymond_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 xymond_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 xymond_rrd tool or writing a separate stream
listener that injects appropriate "trends" data messages back to xymond.

Apart from writing the script, You must also add a section to graphs.cfg(5) so that showgraph.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 xymonserver.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 command-line 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 xymond_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 xymond_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  xymond_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 xymond_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.  xymond_rrd  uses  a different RRD file-format with separate counters for
              packets and bytes and tracks whatever data the system is reporting.