reference(1)

NAME

reference - MRTG 2.9.29 configuration reference

OVERVIEW

The runtime behaviour of MRTG is governed by a configura
tion file. Run-of- ther-mill configuration files can be
generated with cfgmaker. (Check cfgmaker). But for more elaborate configurations some hand-tuning is required.

This document describes all the configuration options
understood by the mrtg software.

SYNTAX

MRTG configuration file syntax follows some simple rules:

� Keywords must start at the beginning of a line.

� Lines which follow a keyword line which start with a: blank are appended to the keyword line
� Empty Lines are ignored
� Lines starting with a # sign are comments.
� You can add other files into the configuration file: using; Include: file; Example:

Include: base-options.inc; If included files are specified with relative paths,
both the current working directory and the directory
containing the main config file will be searched for
the files.

GLOBAL KEYWORDS

WorkDir

WorkDir specifies where the logfiles and the webpages
should be created.

Example:: WorkDir: /usr/tardis/pub/www/stats/mrtg

OPTIONAL GLOBAL KEYWORDS

HtmlDir

HtmlDir specifies the directory where the html (or shtml,
but we'll get on to those later) lives.

NOTE: Workdir overrides the settings for htmldir, imagedir
and logdir.

Example:: Htmldir: /www/mrtg/
ImageDir
ImageDir specifies the directory where the images live. They should be under the html directory.
Example:: Imagedir: /www/mrtg/images
LogDir
LogDir specifies the directory where the logs are stored. This need not be under htmldir directive.
Example:: Logdir: /www/mrtg/logs
Forks (UNIX only)
With system that supports fork (UNIX for example), mrtg can fork itself into multiple instances while it is acquiring data via snmp.
For situations with high latency or a great number of devices this will speed things up considerably. It will not make things faster, though, if you query a single switch sitting next door.
As far as I know NT can not fork so this option is not available on NT.
Example:: Forks: 4
Refresh
How many seconds apart should the browser (Netscape) be instructed to reload the page? If this is not defined, the default is 300 seconds (5 minutes).
Example:: Refresh: 600
Interval
How often do you call mrtg? The default is 5 minutes. If you call it less often, you should specify it here. This does two things:
� The generated HTML page contains the right information: about the calling interval ...
� A META header in the generated HTML page will instruct: caches about the time-to-live of this page .....
In this example, we tell mrtg that we will be calling it every 10 minutes. If you are calling mrtg every 5 minutes, you can leave this line commented out.
Example:: Interval: 10
Note that unless you are using rrdtool you can not set Interval to less than 5 minutes. If you are using rrdtool you can set interval down to 1 minute. Note though, set ting the Interval for an rrdtool/mrtg setup will influence the initial creation of the database. If you change the interval later, all existing databases will remain at the resolution they were initially created with.
WriteExpires
With this switch mrtg will generate .meta files for CERN and Apache servers which contain Expiration tags for the html and gif files. The *.meta files will be created in the same directory as the other files, so you will have to set "MetaDir ." and "MetaFiles on" in your apache.conf or .htaccess file for this to work
NOTE: If you are running Apache-1.2 or later, you can use the mod_expire to achieve the same effect ... see the file htaccess.txt
Example:: WriteExpires: Yes
NoMib2
Normally we ask the SNMP device for 'sysUptime' and 'sys Name' properties. Some do not have these. If you want to avoid getting complaints from mrtg about these missing properties, specify the nomib2 option.
An example of agents which do not implement base mib2 attributes are Computer Associates - Unicenter TNG Agents. CA relies on using the base OS SNMP agent in addition to its own agents to supplement the management of a system.
Example:: NoMib2: Yes
SingleRequest
Some SNMP implementations can not deal with requests ask ing for multiple snmp variables in one go. Set this in your cfg file to force mrtg to only ask for one variable per request.
Examples: SingleRequest: Yes
SnmpOptions
Apart from the per target timeout options, you can also configure the behaviour of the snmpget process on a more profound level. SnmpOptions accepts a hash of options. The following options are currently supported:: timeout => $default_timeout,
retries => $default_retries,
backoff => $default_backoff,
default_max_repetitions => $max_repetitions,
lenient_source_port_matching => 0,
lenient_source_address_matching => 1
The values behind the options indicate the current default value. Note that these settings OVERRIDE the per target timeout settings.
Example:: SnmpOptions: retries => 2, only_ip_address_matching => 0
Note that AS/400 snmp seems to be broken in a way which prevents mrtg from working with it unless: SnmpOptions: lenient_source_port_matching => 1
is set.
IconDir
If you want to keep the mrtg icons in someplace other than the working (or imagedir) directory, use the IconDir vari able for defining the url of the icons directory.
Example:: IconDir: /mrtgicons/
LoadMIBs
Load the MIB file(s) specified and make its OIDs available as symbolic names. For better efficiancy, a cache of MIBs is maintained in the WorkDir.
Example:: LoadMIBs: /dept/net/mibs/netapp.mib,/usr/lo; cal/lib/ft100m.mib
Language
Switch output format to the selected Language (Check the translate directory to see which languages are supported at the moment. In this directory you can also find instructions on how to create new translations).
Currently the following laguages are supported:
big5 brazilian bulgarian catalan chinese croatian czech danish dutch eucjp french galician gb gb2312 german greek hungarian icelandic indonesia iso2022jp italian korean lithuanian malay norwegian polish portuguese romanian rus sian russian1251 serbian slovak slovenian spanish swedish turkish ukrainian
Example:: Language: danish
LogFormat
Setting LogFormat to 'rrdtool' in your mrtg.cfg file
enables rrdtool mode. In rrdtool mode, mrtg relies on
rrdtool to do its logging. Graphs and html pages will be generated on the fly by the 14all.cgi which can be found
in the contrib section together with a short readme ...
This feature has been contributed by Rainer Baw
idamann <bawidama@users.sourceforge.net>. Please check his
website for more information:
http://www.wh-hms.uni-ulm.de/~widi/14all/
Example:: LogFormat: rrdtool
LibAdd
If you are using rrdtool mode and your rrdtool Perl module (RRDs.pm) is not installed in a location where perl can
find it on its own, you can use LibAdd to supply an appro
priate path.
Example:: LibAdd: /usr/local/rrdtool/lib/perl/
PathAdd
If the rrdtool executable can not be found in the normal "PATH", you can use this keyword to add a suitable direc
tory to your path.
Example:: PathAdd: /usr/local/rrdtool/bin/
RunAsDaemon
The RunAsDaemon keyword enables daemon mode operation. The purpose of daemon mode is that MRTG is launched once and not repeatedly (as it is with cron). This behavior saves computing resourses as loading and parsing of configura tion files happens only once.
Using daemon mode MRTG itself is responible for timing the measurement intervals. Therfore its important to set the Interval keyword to an apropiate value.
Note that when using daemon mode MRTG should no longer be started from cron as each new process runs forever. Instead MRTG should be started from the command prompt or by a system startup script.
If you want mrtg to run under a particular user and group
(it is not recomended to run MRTG as root) then you can
use the --user=user_name and --group=group_name options on the mrtg commandline.: mrtg --user=mrtg_user --group=mrtg_group mrtg.cfg
Also note that in daemon mode restarting the process is required in order to activate changes in the config file.
Under UNIX, the Daemon switch causes mrtg to fork into background after checking its config file. On Windows NT the MRTG process will detach from the console, but because the NT/2000 shell waits for its children you have to use this special start sequence when you launch the program:: start /b perl mrtg mrtg.cfg
You may have to add path information equal to what you add when you run mrtg from the commandline.
Example: RunAsDaemon:Yes
Interval:5
This makes MRTG run as a daemon beginning data collection every 5 minutes

PER TARGET CONFIGURATION

Each monitoring target must be identified by a unique
name. This name must be appended to each parameter belong
ing to the same target. The name will also be used for
naming the generated webpages, logfiles and images for
this target.

Target

With the Target keyword you tell mrtg what it should moni
tor. The Target keyword takes arguments in a wide range of formats:

Basic: The most basic format is "port:community@router" This
will generate a traffic graph for the interface 'port'
of the host 'router' (dns name or IP address) and it
will use the community 'community' (snmp password) for
the snmp query.; Example:

Target[ezwf]: 2:public@wellfleet-fddi.ethz.ch; If your community contains a "@" or a " " these char
acters must be escaped with a "

Target[bla]: 2:stu pi@d@router; SNMPv2c
If you have a fast router you might want to try to
poll the ifHC* counters. This feature gets activated
by switching to SNMPv2c. Unfortunately not all devices
support SNMPv2c yet. If it works, this will prevent
your counters from wraping within the 5 minute polling
interval, since we now use 64 bit instead of the nor
mal 32 bit.

Example:

Target[ezwf]: 2:public@router1:::::2

Reversing

Sometimes you are sitting on the wrong side of the
link, and you would like to have mrtg report Incoming
traffic as Outgoing and vice versa. This can be
achieved by adding the '-' sign in front of the "Tar
get" description. It flips the incoming and outgoing
traffic rates.

Example:

Target[ezci]: -1:public@ezci-ether.ethz.ch

Explicit OIDs

You can also explicitly define which OID to query by
using the following syntax 'OID_1&OID_2:commu
nity@router' The following example will retrieve error
counts for input and output on interface 1. MRTG
needs to graph two variables, so you need to specify
two OID's such as temperature and humidity or error
input and error output.

Example:

Target[ezwf]:

1.3.6.1.2.1.2.2.1.14.1&1.3.6.1.2.1.2.2.1.20.1:public@myrouter

MIB Variables

MRTG knows a number of symbolic SNMP variable names.
See the file mibhelp.txt for a list of known names.
One example are the ifInErrors and ifOutErrors. This
means you can specify the above as:

Example:

Target[ezwf]: ifInErrors.1&ifOutErrors.1:public@my

router

Interface by IP

Sometimes SNMP interface index can change, like when
new interfaces are added or removed. This can cause
all Target entries in your config file to become off
set, causing MRTG to graphs wrong instances etc. MRTG
supports IP address instead of ifindex in target defi
nition. Then MRTG will query snmp device and try to
map IP address to the current ifindex. You can use IP
addresses in every type of target definition by adding
IP address of the numbered interface after OID and
separation char '/'.

Make sure that the given IP address is used on your
same target router, especially when graphing two dif
ferent OIDs and/or interface split by '&' delimiter.

You can tell cfgmaker to generate such references with
the option --ifref=ip.

Example:

Target[ezwf]: /1.2.3.4:public@wellfleet-fddi.ethz.ch
Target[ezci]: -/1.2.3.4:public@ezci-ether.ethz.ch
Target[ezwf]:

1.3.6.1.2.1.2.2.1.14/1.2.3.4&1.3.6.1.2.1.2.2.1.14/1.2.3.4:pub

lic@myrouter
Target[ezwf]: ifInErrors/1.2.3.4&ifOutEr

rors/1.2.3.4:public@myrouter

Interface by Description

If you can not use IP addresses you might want to use
the interface names. This works similar to the IP
address aproach except that the prefix to use is a

instead of a /

You can tell cfgmaker to generate such references with
the option --ifref=descr.

Example:

Target[ezwf]: -Interface2:public@wellfleet-fd

di.ethz.ch
Target[ezci]: --Interface2:public@ezci-ether.ethz.ch
Target[ezwf]: 1.3.6.1.2.1.2.2.1.14-Inter

face2&1.3.6.1.2.1.2.2.1.14-Interface3:public@myrouter
Target[ezwf]: ifInErrors-Interface2&ifOutErrors-In

terface3:public@myrouter

If your description contains a "&", a ":", a "@" or a
" " you can include them but you must escape with a
backlash:

Target[ezwf]: n neyddd:public@hello.router

Interface by Name

This is the only sensible way to reference the inter
faces of your switches.

You can tell cfgmaker to generate such references with
the option --ifref=name.

Example:

Target[ezwf]: #2/11:public@wellfleet-fddi.ethz.ch
Target[ezci]: -#2/11:public@ezci-ether.ethz.ch
Target[ezwf]:

1.3.6.1.2.1.2.2.1.14#3/7&1.3.6.1.2.1.2.2.1.14#3/7:public@myrouter
Target[ezwf]: ifInErrors#3/7&ifOutErrors#3/7:pub

lic@myrouter

If your description contains a "&", a ":", a "@" or a
" " you can include them but you must escape with a
backlash:

Target[ezwf]: # fun:public@hello.router

<Note that the # sign will be interpreted as a comment
character if it is the first non white-space character
on the line.>

Interface by Ethernet Address

When the SNMP interface index changes, you can key
that interface by its 'Physical Address', sometimes
called a 'hard address', which is the SNMP variable
'ifPhysAddress'. Internally, MRTG matches the Physi
cal Address from the *.cfg file to its current index,
and then uses that index for the rest of the session.

You can use the Physical Address in every type of tar
get definition by adding the Physical Address after
the OID and the separation char '!' (analogous to the
IP address option). The Physical address is specified
as '-' delimited octets, such as "0a-0-f1-5-23-18"
(omit the double quotes). Note that some routers use
the same Hardware Ethernet Address for all of their
Interfaces which prevents unique interface identifica
tion. Mrtg will notice such problems and alert you.

You can tell cfgmaker to generate configuration files
with hardware ethernet address references by using the
option --ifref=eth.

Example:

Target[ezwf]: !0a-0b-0c-0d:public@wellfleet-fd

di.ethz.ch
Target[ezci]: -!0-f-bb-05-71-22:public@ezci

ether.ethz.ch
Target[ezwf]:

1.3.6.1.2.1.2.2.1.14!0a-00-10-23-44-51&!0a-00-10-23-44-51:pub

lic@myrouter
Target[ezwf]: ifInErrors!0a-00-10-23-44-51&ifOutEr

rors!0a-00-10-23-44-51:public@myrouter

Interface by Type

It seems that there are devices that try to defy all
monitoring efforts: the interesting interfaces have
neither ifName nor a constant ifDescr not to mention a
persistant ifIndex. The only way to get a constant
mapping is by looking at the interface type, because
the interface you are interested in is unique in the
device you are looking at ...

You can tell cfgmaker to generate such references with
the option --ifref=type.

Example:

Target[ezwf]: %13:public@wellfleet-fddi.ethz.ch
Target[ezci]: -%13:public@ezci-ether.ethz.ch
Target[ezwf]:

1.3.6.1.2.1.2.2.1.14%13&1.3.6.1.2.1.2.2.1.14%14:public@myrouter
Target[ezwf]: ifInErrors%13&ifOutErrors%14:public@my

router

Extended Host Name Syntax

In all places where ``community@router'' is accepted,
you can add additional parameters for the SNMP commu
nication using colon-separated suffixes. The full syn
tax is as follows:

community@router[:[port][:[timeout][:[re

tries][:[backoff][:version]]]]]

where the meaning of each parameter is as follows:

port

the UDP port under which to contact the SNMP agent
(default: 161)

timeout

initial timeout for SNMP queries, in seconds
(default: 2.0)

retries

number of times a timed-out request will be
retried (default: 5)

backoff

factor by which the timeout is multiplied on every
retry (default: 1.0).

version

for SNMP version. If you have a fast router you
might want to put a '2' here. This will make mrtg
try to poll the 64 bit counters and thus prevent
excessive counter wrapping. Not all routers sup
port this though.

Example:

3:public@router1:::::2

A value that equals the default value can be omitted.
Trailing colons can be omitted, too.

Example:

Target[ezci]: 1:public@ezci-ether.ethz.ch:9161::4

This would refer to the input/output octet counters
for the interface with ifIndex 1 on
ezci-ether.ethz.ch, as known by the SNMP agent listen ing on UDP port 9161. The standard initial timeout
(2.0 seconds) is used, but the number of retries is
set to four. The backoff value is the default.

External Monitoring Scripts

If you want to monitor something which does not pro
vide data via snmp you can use some external program
to do the data gathering.

The external command must return 4 lines of output:

Line 1

current state of the first variable, normally
'incoming bytes count'

Line 2

current state of the second variable, normally
'outgoing bytes count'

Line 3

string (in any human readable format), telling the
uptime of the target.

Line 4

string, telling the name of the target.

Depending on the type of data your script returns you
might want to use the 'gauge' or 'absolute' arguments
for the Options keyword.

Example:

Target[ezwf]: `/usr/local/bin/df2mrtg

/dev/dsk/c0t2d0s0`

Note the use of the backticks (`), not apostrophes (')
around the command.

If you want to use a backtick in the command name this
can be done but you must escape it with a backslash
...

If your script does not have any data to return but
does not want mrtg to complain about invalid data, it
can return 'UNKNOWN' instead of a number. Note though
that only rrdtool is realy equipped to handle unknown
data well.

Multi Target Syntax

You can also use several statements in a mathematical
expression. This could be used to aggregate both B
channels in an ISDN connection or multiple T1s that
are aggregated into a single channel for greater band
width. Note the whitespace arround the target defini
tions.

Example:

Target[ezwf]: 2:public@wellfleetA + 1:pub

lic@wellfleetA
* 4:public@ciscoF
MaxBytes
The maximum value either of the two variables monitored are allowed to reach. For monitoring router traffic this is normally the bytes per second this interface port can carry.
If a number higher than MaxBytes is returned, it is ignored. Also read the section on AbsMax for further info. The MaxBytes value is also used in calculating the Y range for unscaled graphs (see the section on Unscaled).
Since most links are rated in bits per second, you need to divide their maximum bandwidth (in bits) by eight (8) in order to get bytes per second. This is very important to make your unscaled graphs display realistic information. T1 = 193000, 56K = 7000, Ethernet = 1250000. The MaxBytes value will be used by mrtg to decide whether it got a valid response from the router.
If you need two different MaxBytes values for the two mon itored variables, you can use MaxBytes1 and MaxBytes2 instead of MaxBytes.
Example:: MaxBytes[ezwf]: 1250000
Title
Title for the HTML page which gets generated for the graph.
Example:: Title[ezwf]: Traffic Analysis for Our Nice Company

OPTIONAL PER TARGET KEYWORDS

PageTop

Things to add to the top of the generated HTML page. Note
that you can have several lines of text as long as the
first column is empty.

Note that the continuation lines will all end up on the
same line in the html page. If you want linebreaks in the
generated html use the '0 sequence.

Example:: PageTop[ezwf]: <H1>Traffic Analysis for ETZ C95.1</H1>
Our Campus Backbone runs over an FDDI line
with a maximum transfer rate of 12.5 megabytes per
Second.; RouterUptime; In cases where you calculate the used bandwidth from sev
eral interfaces you normaly don't get the router uptime
and router name displayed on the web page.; If these interfaces are on the same router and the uptime
and name should be displayed you have to specify its com
munity and address again with the RouterUptime keyword.; Example:

Target[kacisco.comp.edu]: 1:public@194.64.66.250 + 2:pub

lic@194.64.66.250
RouterUptime[kacisco.comp.edu]: public@194.64.66.250; MaxBytes1; Same as MaxBytes, for variable 1.; MaxBytes2; Same as MaxBytes, for variable 2.; PageFoot; Things to add to the bottom of the generated HTML page.
Note that you can have several lines of text as long as
the first column is empty.; Note that the continuation lines will all end up on the
same line in the html page. If you want linebreaks in the
generated html use the '0 sequence.; The material will be added just before the </BODY> tag:; Example:

PageFoot[ezwf]: Contact <A HREF="mailto:peter@x.yz">Pe

ter</A>
if you have questions regarding this page

AddHead

Use this tag like the PageTop header, but its contents
will be added between </TITLE> and </HEAD>.

Example:

AddHead[ezwf]: <link rev="made" href="mail

to:mrtg@blabla.edu">

BodyTag

BodyTag lets you supply your very own <body ...> tag for
the generated webpages.

Example:

BodyTag[ezwf]: <BODY LEFTMARGIN="1" TOPMARGIN="1"
BACKGROUND="/stats/im

ages/bg.neo2.gif">
AbsMax
If you are monitoring a link which can handle more traffic than the MaxBytes value. Eg, a line which uses compression or some frame relay link, you can use the AbsMax keyword to give the absolute maximum value ever to be reached. We need to know this in order to sort out unrealistic values returned by the routers. If you do not set AbsMax, rateup will ignore values higher than MaxBytes.
Example:: AbsMax[ezwf]: 2500000
Unscaled
By default each graph is scaled vertically to make the actual data visible even when it is much lower than MaxBytes. With the Unscaled variable you can suppress this. It's argument is a string, containing one letter for each graph you don't want to be scaled: d=day w=week m=month y=year. There is also a special case to unset the variable completely: n=none. This could be useful in the event you need to override a global configuration. In the example scaling for the yearly and the monthly graph are suppressed.
Example:: Unscaled[ezwf]: ym
WithPeak
By default the graphs only contain the average values of the monitored variables - normally the transfer rates for incoming and outgoing traffic. The following option instructs mrtg to display the peak 5 minute values in the [w]eekly, [m]onthly and [y]early graph. In the example we define the monthly and the yearly graph to contain peak as well as average values.
Examples:: WithPeak[ezwf]: ym
Suppress
By default mrtg produces 4 graphs. With this option you can suppress the generation of selected graphs. The option value syntax is analogous to the above two options. In this example we suppress the yearly graph as it is quite empty in the beginning.
Example:: Suppress[ezwf]: y
Extension
By default, mrtg creates .html files. Use this option to tell mrtg to use a different extension. For example you could set the extension to php3, then you will be able to enclose PHP tags into the output (useful for getting a router name out of a database).
Example:: Extension[ezwf]: phtml
Directory
By default, mrtg puts all the files that it generates for each target (the GIFs, the HTML page, the log file, etc.) in WorkDir.
If the Directory option is specified, the files are instead put into a directory under WorkDir or Log-, Imageand HtmlDir). (For example the Directory option below would cause all the files for a target ezwf to be put into directory /usr/tardis/pub/www/stats/mrtg/ezwf/ .)
The directory must already exist; mrtg will not create it.
Example:: WorkDir: /usr/tardis/pub/www/stats/mrtg
Directory[ezwf]: ezwf
NOTE: the Directory option must always be 'relative' or bad things will happen.
XSize and YSize
By default mrtgs graphs are 100 by 400 pixels wide (plus some more for the labels. In the example we get almost square graphs ...
Note: XSize must be between 20 and 600; YSize must be larger than 20
Example:: XSize[ezwf]: 300
YSize[ezwf]: 300
XZoom and YZoom
If you want your graphs to have larger pixels, you can "Zoom" them.
Example:: XZoom[ezwf]: 2.0
YZoom[ezwf]: 2.0
XScale and YScale
If you want your graphs to be actually scaled use XScale and YScale. (Beware: while this works, the results look ugly (to be frank) so if someone wants to fix this: patches are welcome.
Example:: XScale[ezwf]: 1.5
YScale[ezwf]: 1.5
YTics and YTicsFactor
If you want to show more than 4 lines per graph, use YTics. If you want to scale the value used for the YLe gend of these tics, use YTicsFactor. The default value for YTics is 4 and the default value for YTicsFactor is 1.0 .
Example:: Suppose you get values ranging from 0 to 700.
You want to plot 7 lines and want to show
0, 1, 2, 3, 4, 5, 6, 7 instead of 0, 100, 200,
300, 400, 500, 600, 700. You should write then:; YTics[ezwf]: 7
YTicsFactor[ezwf]: 0.01
Factor
If you want to multiply all numbers shown below the graph with a constant factor, use this directive to define it ..
Example:: Factor[as400]: 4096
Step
Change the default step from 5 * 60 seconds to something else (I have not tested this much ...)
Example:: Step[ezwf]: 60
Options
The Options Keyword allows you to set some boolean switches:
growright: The graph grows to the left by default. This option
flips the direction of growth causing the current time
to be at the right edge of the graph and the history
values to the left of it.
bits: All the monitored variable values are multiplied by 8
(i.e. shown in bits instead of bytes) ... looks much
more impressive :-) It also affects the 'factory
default' labeling and units for the given target.
perminute: All the monitored variable values are multiplied by 60
(i.e. shown in units per minute instead of units per
second) in case of small values more accurate graphs
are displayed. It also affects the 'factory default'
labeling and units for the given target.
perhour: All the monitored variable values are multiplied by
3600 (i.e. shown in units per hour instead of units
per second) in case of small values more accurate
graphs are displayed. It also affects the 'factory
default' labeling and units for the given target.
noinfo: Suppress the information about uptime and device name
in the generated webpage.
nopercent: Don't print usage percentages.
transparent: Make the background of the generated gifs transparent.
integer: Print summary lines below graph as integers without
commas.
dorelpercent: The relative percentage of IN-traffic to OUT-traffic
is calculated and displayed in the graph as an addi
tional line. Note: Only a fixed scale is available
(from 0 to 100%). Therefore if IN-traffic is greater
than OUT-traffic then 100% is displayed. If you sus
pect that your IN-traffic is not always less than or
equal to your OUT-traffic you are urged to not use
this options. Note: If you use this option in combi
nation with the Colours options, a fifth colour-name colour-value pair is required there.
avgpeak: There are some ISPs who use the average Peak values to
bill their customers. Using this option MRTG displays
these values for each graph. The value is built by
averaging the max 5 minute traffic avarage for each
'step' shown in the graph. For the Weekly graph this
means that it builds the average of all 2 hour inter
vals 5 minute peak values. (Confused? Thought so!)
gauge: Treat the values gathered from target as 'current sta
tus' measurements and not as ever incrementing coun
ters. This would be useful to monitor things like
disk space, processor load, temperature, and the like
...; In the absence of 'gauge' or 'absolute' options, MRTG
treats variables as a counters and calculates the dif
ference between the current and the previous value and
divides that by the elapsed time between the last two
readings to get the value to be plotted.
absolute: This is for counter type data sources which reset
their value when they are read. This means that rateup
does not have to build the difference between the cur
rent and the last value read from the data source. The
value obtained is still divided by the elapsed time
between the current and the last reading, which makes
it different from the 'gauge' option. Useful for
external data gatherers.
unknaszero: Log unknown data as zero instead of the default
behaviour of repeating the last value seen. Be careful
with this, often a flat line in the graph is much more
obvious than a line at 0.
withzeroes: Normally we ignore all values which are zero when cal
culating the average transfer rate on a line. If this
is not desirable use this option.
noborder: If you are using rateup to log data, MRTG will create
the graph images. Normally these images have a shaded
border around them. If you do not want the border to
be drawn, enable this option. This option has no
effect if you are not using rateup.
noarrow: As with the option above, this effects rateup graph
generation only. Normally rateup will generate graphs
with a small arrow showing the direction of the data.
If you do not want this arrow to be drawn, enable this
option. This option has no effect if you are not using
rateup.
noi When using rateup for graph generation, you can use: this option to stop rateup drawing a graph for the 'I'
or first variable. This also removes entries for this
variable in the HTML page MRTG generates, and will
remove the peaks for this variable if they are
enabled. This allows you to hide this data, or can be
very useful if you are only graphing one line of data
rather than two. This option is not destructive - any
data received for the the variable continued to be
logged, it just isn't shown.
noo Same as above, except relating to the 'O' or second: variable.
nobanner: When using rateup for graph generation, this option
disables MRTG adding the MRTG banner to the HTML pages
it generates.
nolegend: When using rateup for graph generation, this option
will stop MRTG from creating a legend at the bottom of
the HTML pages it generates.
Example:: Options[ezwf]: growright, bits
kilo
Use this option to change the multiplier value for build ing prefixes. Defaultvalue is 1000. This tag is for the special case that 1kB = 1024B, 1MB = 1024kB and so far.
Example:: kilo[ezwf]: 1024
kMG
Change the default multiplier prefixes (,k,M,G,T,P). In the tag ShortLegend define only the basic units. Format: Comma seperated list of prefixed. Two consecutive commas or a comma at start or end of the line gives no prefix on this item. Note: If you do not want prefixes, then leave this line blank.
Example: velocity in nm/s (nanometers per second) dis played in nm/h.: ShortLegend[ezwf]: m/h
kMG[ezwf]: n,u,m,,k,M,G,T,P
options[ezwf]: perhour
Colours
The Colours tag allows you to override the default colour scheme. Note: All 4 of the required colours must be spec ified here. The colour name ('Colourx' below) is the leg end name displayed, while the RGB value is the real colour used for the display, both on the graph and in the html doc.
Format is: Col1#RRGGBB,Col2#RRGGBB,Col3#RRGGBB,Col4#RRGGBB
Important: If you use the dorelpercent options tag a fifth colour name colour value pair is required: Col1#RRGGBB,Col2#RRGGBB,Col3#RRGGBB,Col4#RRGGBB,Col5#RRGG
BB
Colour1: First variable (normally Input) on default graph.
Colour2: Second variable (normally Output) on default graph.
Colour3: Max first variable (input).
Colour4: Max second variable (output).
RRGGBB: 2 digit hex values for Red, Green and Blue.
Example:: Colours[ezwf]: GREEN#00eb0c,BLUE#1000ff,DARK; GREEN#006600,VIOLET#ff00ff
Background
With the Background tag you can configure the background colour of the generated HTML page.
Example:: Background[ezwf]: #a0a0a0a
YLegend, ShortLegend, Legend[1234]
The following keywords allow you to override the text dis played for the various legends of the graph and in the HTML document:
YLegend: The Y-axis label of the graph. Note that a text which
is too long to fit in the graph will be silently
ignored.
ShortLegend: The units string (default 'b/s') used for Max, Average
and Current
Legend[1234IO]: The strings for the colour legend.
Example:: YLegend[ezwf]: Bits per Second
ShortLegend[ezwf]: b/s
Legend1[ezwf]: Incoming Traffic in Bits per Second
Legend2[ezwf]: Outgoing Traffic in Bits per Second
Legend3[ezwf]: Maximal 5 Minute Incoming Traffic
Legend4[ezwf]: Maximal 5 Minute Outgoing Traffic
LegendI[ezwf]:  In:
LegendO[ezwf]:  Out:
Note, if LegendI or LegendO are set to an empty string with: LegendO[ezwf]:
The corresponding line below the graph will not be printed at all.
Timezone
If you live in an international world, you might want to generate the graphs in different timezones. This is set in the TZ variable. Under certain operating systems like Solaris, this will provoke the localtime call to give the time in the selected timezone.
Example:: Timezone[ezwf]: Japan
The Timezone is the standard Solaris timezone, ie Japan, Hongkong, GMT, GMT+1 etc etc.
Weekformat
By default, mrtg (actually rateup) uses the strftime(3) '%W' option to format week numbers in the monthly graphs. The exact semantics of this format option vary between systems. If you find that the week numbers are wrong, and your system's strftime(3) routine supports it, you can try another format option. The POSIX '%V' option seems to correspond to a widely used week numbering convention. The week format character should be specified as a single letter; either W, V, or U.
Example:: Weekformat[ezwf]: V
RRDRowCount
This affects the creation of new rrd files. By default rrds are created to hold about 1 day's worth of high reso lution data. (plus 1 week of 30 minute data, 2 months of 2 hour data and 2 years of 1 day data). With this Keyword you can change the number of base interval entries config ured for new rrds as they get created. Note that you must take the interval time into account.
Example:: RRDRowCount[ezwf]: 1600

THRESHOLD CHECKING

Through its threshold checking functionality mrtg is able
to detect threshold problems for the various targets and
can call external scripts to handle those problems (e.g.
send email or a page to an administrator).

Threshold checking is configured through the following
parameters:

ThreshDir (GLOBAL)

By defining ThreshDir to point to a writable directory,
MRTG will only alert you when a threshold boundery has
been crossed.

Example:: ThreshDir: /var/mrtg/thresh
ThreshMinI (PER TARGET)
This is the minimum acceptable value for the Input (first) parameter. If the parameter falls below this value, the program specified in ThreshProgI will be run. If the value ends in '%' then the threshold is defined relative to MaxBytes.
ThreshMaxI (PER TARGET)
This is the maximum acceptable value for the Input (first) parameter. If the parameter falls above this value, the program specified in ThreshProgI will be run. If the value ends in '%' then the threshold is defined relative to MaxBytes.
ThreshDesc (PER TARGET)
Its value will be assigned to the environment variable THRESH_DESC before any of the programs mentioned below are called. The programms can use the value of this variable to produce more user-friendly output.
ThreshProgI (PER TARGET)
This defines a program to be run if ThreshMinI or Thresh MaxI is broken. MRTG passes 3 arguments: the $router variable, the threshold value broken, and the current parameter value.
ThreshProgOKI (PER TARGET)
This defines a program to be run if the parameter is cur rently OK (based on ThreshMinI and ThreshMaxI), but wasn't OK on the previous running -- based on the files found in ThreshDir. MRTG passes 3 arguments: the $router variable the unbroken threshold value, and the current parameter value.
ThreshMinO, ThreshMaxO, ThreshProgO, and ThreshProgOKO
These work the same as their *I counterparts, except on the Output (second) parameter.
Note that you can use the SetEnv parameter explained above to pass additional information to the threshold programs.
SetEnv
When calling threshold scripts from within your cfg file you might want to pass some data on to the script. This can be done with the SetEnv configuration option which takes a series of environment variable assignments. Note that the quotes are mandatory. This does not work for external scripts. It is not possible to set environment variables per target.
Example:: SetEnv[myrouter]: EMAIL="contact_email@someplace.net"
HOST="www.some_server.net"
URL="http://www.some_serv

er.net/path/mrtg.html"

PER TARGET DEFAULT VALUES

Pre- and Postfix

To save yourself some typing you can define a target
called '^'. The text of every Keyword you define for this
target will be PREPENDED to the corresponding Keyword of
all the targets defined below this line. The same goes for
a Target called '$' but its text will be APPENDED.

Note that a space is inserted between the prepended text
and the Keyword value, as well as between the Keyword
value and the appended text. This works well for text-val
ued Keywords, but is not very useful for other Keywords.
See the "default" target description below.

The example will make mrtg use a common header and a com
mon contact person in all the pages generated from targets
defined later in this file.

Example:: PageTop[^]: <H1>NoWhere Unis Traffic Stats</H1><HR>
PageTop[$]: Contact Peter Norton if you have any ques; tions<HR>
To remove the prepend/append value, specify an empty value, e.g.:: PageTop[^]:
PageTop[$]:
NOTE: With PREPEND and APPEND there is normally a space inserted between the local value and the PRE- or APPEND value. Sometimes this is not desirable. You can use the NoSpaceChar config option to define a character which can be mentioned at the end of a $ or ^ definition in order to supress the space.
Example:: NoSpaceChar: ~
Target[^]:; 1.3.6.1.4.1.482.50.2.4.20.0&1.3.6.1.4.1.482.50.2.4.21.0:get@~
Target[a]: a.tolna.net
Target[b]: b.tolna.net
Target[c]: c.tolna.net
Target[d]: d.tolna.net
Default Values
The target name '_' specifies a default value for that Keyword. In the absence of explicit Keyword value, the prepended and the appended keyword value, the default value will be used.
Example:: YSize[_]: 150
Options[_]: growright,bits,nopercent
WithPeak[_]: ymw
Suppress[_]: y
MaxBytes[_]: 1250000
To remove the default value and return to the 'factory default', specify an empty value, e.g.:: YLegend[_]:
There can be several instances of setting the default/prepend/append values in the configuration file. The later setting replaces the previous one for the rest of the configuration file. The default/prepend/append values used for a given keyword/target pair are the ones that were in effect at the point in the configuration file where the target was mentioned for the first time.
Example:: MaxBytes[_]: 1250000
Target[myrouter.somplace.edu.2]: 2:public@myrouter.som; place.edu
MaxBytes[_]: 8000
Title[myrouter.somplace.edu.2]: Traffic Analysis for my; router.somplace.edu IF 2
The default MaxBytes for the target myrouter.some place.edu.2 in the above example will be 1250000, which was in effect where the target name myrouter.some place.edu.2 first appeared in the config file.

COMMAND LINE OPTIONS

--user username and --group groupname: Run as the given user and/or group. (Unix Only)
--lock-file filename: Use an alternate lock-file (the default is to use the
configuration-file appended with "_l").
--confcache-file filename: Use an alternate confcache-file (the default is to use
the configuration-file appended with ".ok")
--logging filename|eventlog: If this is set to writable filename, all output from
mrtg (warnings, debug messages, errors) will go to
filename. If you are running on Win32 you can specify eventlog instead of a filename which will send all error to the windows event log.; NOTE:Note, there is no Message DLL for mrtg. This has
the side effect that the windows event logger will
display a nice message with every entry in the event
log, complaing about the fact that mrtg has no message
dll. If any of the Windows folks want to contribute
one, they are welcome.
--check: Only check the cfg file for errors. Do not do any
thing.
--pid-file=s: Define the name and path of the pid file for mrtg run
ning as a daemon
--debug=s: Enable debug options. The argument of the debug option
is a comma separated list of debug values:

cfg - watch the config file reading
dir - directory mangeling
base - basic program flow
tarp - target parser
snpo - snmp polling
fork - forking view
time - some timing info
log - logging of data via rateup or rrdtool; Example:

--debug="cfg,snpo"

EXAMPLES

Minimal mrtg.cfg: WorkDir: /usr/tardis/pub/www/stats/mrtg
Target[r1]: 2:public@myrouter.somplace.edu
MaxBytes[r1]: 8000
Title[r1]: Traffic Analysis ISDN
PageTop[r1]: <H1>Stats for our ISDN Line</H1>
Cfg for several Routers.: WorkDir: /usr/tardis/pub/www/stats/mrtg
Title[^]: Traffic Analysis for
PageTop[^]: <H1>Stats for
PageTop[$]: Contact The Chief if you notice anybody<HR>
MaxBytes[_]: 8000
Options[_]: growright; Title[isdn]: our ISDN Line
PageTop[isdn]: our ISDN Line</H1>
Target[isdn]: 2:public@router.somplace.edu; Title[backb]: our Campus Backbone
PageTop[backb]: our Campus Backbone</H1>
Target[backb]: 1:public@router.somplace.edu
MaxBytes[backb]: 1250000; # the following line removes the default prepend value
# defined above; Title[^]:; Title[isdn2]: Traffic for the Backup ISDN Line
PageTop[isdn2]: our ISDN Line</H1>
Target[isdn2]: 3:public@router.somplace.edu

AUTHOR

Tobias Oetiker <oetiker@ee.ethz.ch> and many contributors

docs.sk

comprehensive documentation repository

See also