MRTG-REFERENCE(1) mrtg MRTG-REFERENCE(1)
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mrtg-reference - MRTG 2.14.7 configuration reference
OOVVEERRVVIIEEWW
The runtime behaviour of MRTG is governed by a configura-
tion file. Run-of- ther-mill configuration files can be
generated with ccffggmmaakkeerr. (Check cfgmaker). But for more
elaborate configurations some hand-tuning is required.
This document describes all the configuration options
understood by the mrtg software.
SSYYNNTTAAXX
MRTG configuration file syntax follows some simple rules:
+o Keywords must start at the beginning of a line.
+o Lines which follow a keyword line which start with a
blank are appended to the keyword line
+o Empty Lines are ignored
+o Lines starting with a # sign are comments.
+o You can add other files into the configuration file
using
IInncclluuddee:: _f_i_l_e
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.
GGLLOOBBAALL KKEEYYWWOORRDDSS
WWoorrkkDDiirr
WorkDir specifies where the logfiles and the webpages
should be created.
Example:
WorkDir: /usr/tardis/pub/www/stats/mrtg
OOPPTTIIOONNAALL GGLLOOBBAALL KKEEYYWWOORRDDSS
HHttmmllDDiirr
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/
IImmaaggeeDDiirr
ImageDir specifies the directory where the images live.
They should be under the html directory.
Example:
Imagedir: /www/mrtg/images
LLooggDDiirr
LogDir specifies the directory where the logs are stored.
This need not be under htmldir directive.
Example:
Logdir: /www/mrtg/logs
FFoorrkkss ((UUNNIIXX oonnllyy))
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
EEnnaabblleeIIPPvv66
When set to yes, IPv6 support is enabled if the required
libraries are present (see the mrtg-ipv6 manpage). When
IPv6 is enabled, mrtg can talk to routers using SNMP over
IPv6 and targets may be specified by their numeric IPv6
addresses as well as by hostname or IPv4 address.
If IPv6 is enabled and the target is a hostname, mrtg will
try to resolve the hostname to an IPv6 address and, if
this fails, to an IPv4 address. Note that mrtg will only
use IPv4 if you specify an IPv4 address or a hostname with
no corresponding IPv6 address; it will not fall back to
IPv4 if it simply fails to communicate with the target
using IPv6. This is by design.
Note that many routers do not currently support SNMP over
IPv6. Use the _I_P_v_4_O_n_l_y per target option for these
routers.
IPv6 is disabled by default.
Example:
EnableIPv6: Yes
EEnnaabblleeSSnnmmppVV33
When set to yes, uses the Net::SNMP module instead of the
SNMP_SESSION module for generating snmp queries. This
allows the use of SNMPv3 if other snmpv3 parameters are
set.
SNMPv3 is disabled by default.
Example:
EnableSnmpV3: yes
RReeffrreesshh
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
IInntteerrvvaall
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:
+o The generated HTML page contains the right information
about the calling interval ...
+o 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.
MMaaxxAAggee
MRTG relies heavily on the real time clock of your com-
puter. If the time is set to a wrong value, especially if
it is advanced far into the future, this will cause mrtg
to expire lots of supposedly old data from the log files.
To prevent this, you can add a 'reasonability' check by
specifying a maximum age for log files. If a file seems to
be older, mrtg will not touch it but complain instead,
giving you a chance to investigate the cause.
Example:
MaxAge: 7200
The example above will make mrtg refuse to update log
files older than 2 hours (7200 seconds).
WWrriitteeEExxppiirreess
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
NNooMMiibb22
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
SSiinngglleeRReeqquueesstt
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
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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,
use_16bit_request_ids => 1,
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.
A per-target SnmpOptions[] keyword will override the
global settings. That keyword is primarily for SNMPv3.
The 16bit request ids are the only way to query the broken
SNMP implementation of SMC Barricade routers.
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.
IIccoonnDDiirr
If you want to keep the mrtg icons in someplace other than
the working (or imagedir) directory, use the _I_c_o_n_D_i_r vari-
able for defining the url of the icons directory.
Example:
IconDir: /mrtgicons/
LLooaaddMMIIBBss
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/local/lib/ft100m.mib
LLaanngguuaaggee
Switch output format to the selected Language (Check the
_t_r_a_n_s_l_a_t_e 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
LLooggFFoorrmmaatt
Setting LogFormat to 'rrdtool' in your mrtg.cfg file
enables rrdtool mode. In rrdtool mode, mrtg relies on
rrrrddttooooll to do its logging. See mrtg-rrd.
Example:
LogFormat: rrdtool
LLiibbAAdddd
If you are using rrdtool mode and your rrrrddttooooll 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/
PPaatthhAAdddd
If the rrrrddttooooll 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/
RRuunnAAssDDaaeemmoonn
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 ----uusseerr==_u_s_e_r___n_a_m_e and ----ggrroouupp==_g_r_o_u_p___n_a_m_e 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
If you are daemontools and still want to run mrtg as a
daemon you can additionally specify
NoDetach: Yes
this will make mrtg run but without detaching it from the
terminal.
CCoonnvveerrssiioonnCCooddee
Some devices may produce non-numeric values that would
nevertheless be useful to graph with MRTG if those values
could be converted to numbers. The ConversionCode keyword
specifies the path to a file containing Perl code to per-
form such conversions. The code in this file must consist
of one or more Perl subroutines. Each subroutine must
accept a single string argument and return a single
numeric value. When RRDtool is in use, a decimal value may
be returned. When the name of one of these subroutines is
specified in a target definition (see below), MRTG calls
it twice for that target, once to convert the the input
value being monitored and a second time to convert the
output value. The subroutine must return an undefined
value if the conversion fails. In case of failure, a warn-
ing may be posted to the MRTG log file using Perl's warn
function. MRTG imports the subroutines into a separate
name space (package MRTGConversion), so the user need not
worry about pollution of MRTG's global name space. MRTG
automatically prepends this package declaration to the
user-supplied code.
Example: Suppose a particular OID returns a character
string whose length is proportional to the value to be
monitored. To convert this string to a number that can be
graphed by MRTG, create a file arbitrarily named "MyCon-
versions.pl" containing the following code:
# Return the length of the string argument
sub Length2Int {
my $value = shift;
return length( $value );
}
Then include the following global keyword in the MRTG con-
figuration file (assuming that the conversion code file is
saved in the mrtg/bin directory along with mrtg itself):
ConversionCode: MyConversions.pl
This will cause MRTG to include the definition of the sub-
routine Length2Int in its execution environment.
Length2Int can then be invoked on any target by appending
"|Length2Int" to the target definition as follows:
Target[myrouter]: 1.3.6.1.4.1.999.1&1.3.6.1.4.1.999.1:public@mydevice|Length2Int
See "Extended Host Name Syntax" below for complete target
definition syntax information.
PPEERR TTAARRGGEETT CCOONNFFIIGGUURRAATTIIOONN
Each monitoring target must be identified by a unique
name. This name must be appended to each parameter
belonging to the same target. The name will also be used
for naming the generated webpages, logfiles and images for
this target.
TTaarrggeett
With the _T_a_r_g_e_t keyword you tell mrtg what it should moni-
tor. The _T_a_r_g_e_t 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[myrouter]: 2:public@wellfleet-fddi.domain
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[myrouter]: 2:public@router1:::::2
SNMPv3
As an alternative to SNMPv2c, SNMPv3 provides access
to the ifHC* counters, along with encryption. Not all
devices support SNMPv3, and you will also need the
perl Net::SNMP library in order to use it. It is rec-
ommended that cfgmaker be used to generate configura-
tions involving SNMPv3, as it will check if the
Net::SNMP library is loadable, and will switch to
SNMPv2c if v3 is unavailable.
SNMP v3 requires additional authentication parameters,
passed using the SnmpOptions[] per-target keyword.
Example:
Target[myrouter]: 2:router1:::::3
SnmpOptions[myrouter]: username=>'user1'
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.domain
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[myrouter]: 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[myrouter]: ifInErrors.1&ifOutErrors.1:public@myrouter
SnmpWalk
It may be that you want to monitor an snmp object that
is only reachable by 'walking'. You can get mrtg to
walk by prepending the OID with the string WWaaLLKK or if
you want a particular entry from the table returned by
the walk you can use WWaaLLKK_x where _x is a number start-
ing from 0 (!).
Example:
Target[myrouter]: WaLKstrangeOid.1&WaLKstrangeOid.2:public@myrouter
Target[myrouter]: WaLK3strangeOid.1&WaLK4strangeOid.2:public@myrouter
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 ----iiffrreeff==iipp.
Example:
Target[myrouter]: /1.2.3.4:public@wellfleet-fddi.domain
Target[ezci]: -/1.2.3.4:public@ezci-ether.domain
Target[myrouter]: 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:public@myrouter
Target[myrouter]: ifInErrors/1.2.3.4&ifOutErrors/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 ----iiffrreeff==ddeessccrr.
Example:
Target[myrouter]: \My-Interface2:public@wellfleet-fddi.domain
Target[ezci]: -\My-Interface2:public@ezci-ether.domain
Target[myrouter]: 1.3.6.1.2.1.2.2.1.14\My-Interface2&1.3.6.1.2.1.2.2.1.14\My-Interface3:public@myrouter
Target[myrouter]: ifInErrors\My-Interface2&ifOutErrors\My-Interface3:public@myrouter
If your description contains a "&", a ":", a "@" or a
" " you can include them but you must escape with a
backlash:
Target[myrouter]: \fun\:\ ney\&ddd: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 ----iiffrreeff==nnaammee.
Example:
Target[myrouter]: #2/11:public@wellfleet-fddi.domain
Target[ezci]: -#2/11:public@ezci-ether.domain
Target[myrouter]: 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[myrouter]: ifInErrors#3/7&ifOutErrors#3/7:public@myrouter
If your description contains a "&", a ":", a "@" or a
" " you can include them but you must escape with a
backlash:
Target[myrouter]: #\:\ 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 ----iiffrreeff==eetthh.
Example:
Target[myrouter]: !0a-0b-0c-0d:public@wellfleet-fddi.domain
Target[ezci]: -!0-f-bb-05-71-22:public@ezci-ether.domain
Target[myrouter]: 1.3.6.1.2.1.2.2.1.14!0a-00-10-23-44-51&!0a-00-10-23-44-51:public@myrouter
Target[myrouter]: ifInErrors!0a-00-10-23-44-51&ifOutErrors!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 ----iiffrreeff==ttyyppee.
Example:
Target[myrouter]: %13:public@wellfleet-fddi.domain
Target[ezci]: -%13:public@ezci-ether.domain
Target[myrouter]: 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[myrouter]: ifInErrors%13&ifOutErrors%14:public@myrouter
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. You can also
append a pipe symbol ( | ) and the name of a numeric
conversion subroutine as described under the global
keyword "ConversionCode" above. The full syntax is as
follows:
community@router[:[port][:[timeout][:[retries][:[backoff][:[version]][|name]]]]]
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. For authenticated
or encrypted SNMP, you can try to put a '3' here.
This will make mrtg try to poll the 64 bit coun-
ters and thus prevent excessive counter wrapping.
Not all routers support this though. SNMP v3
requires additional setup, see SnmpOptions[] for
full details.
Example:
3:public@router1:::::2
name
the name of the subroutine that MRTG will call to
convert the input and output values to integers.
See the complete example under the global keyword
"ConversionCode" above.
Example:
1.3.6.1.4.1.999.1&1.3.6.1.4.1.999.2:public@mydevice:161::::2|Length2Int
This would retrieve values from the OID
1.3.6.1.4.1.999.1 for input and .2 for output on
mydevice using UDP port 161 and SNMP version 2,
and would execute the user-defined numeric conver-
sion subroutine Length2Int to convert those values
to integers.
A value that equals the default value can be omitted.
Trailing colons can be omitted, too. The pipe symbol
followed by the name parameter, if present, must come
at the end. There must be no spaces around the colons
or pipe symbol.
Example:
Target[ezci]: 1:public@ezci-ether.domain:9161::4
This would refer to the input/output octet counters
for the interface with _i_f_I_n_d_e_x _1 on _e_z_c_i_-_e_t_h_e_r_._d_o_m_a_i_n,
as known by the SNMP agent listening 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.
Numeric IPv6 addresses
If IPv6 is enabled you may also specify a target using
its IPv6 address. To avoid ambiguity with the port
number, numeric IPv6 addresses must be placed in
square brackets.
Example:
Target[IPv6test]: 2:public@[2001:760:4::]:6161::4
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 _O_p_t_i_o_n_s keyword.
Example:
Target[myrouter]: `/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 combine several target definitions in a
mathematical expression. Any syntactically correct
expression that the Perl interpreter can evaluate to
will work. An expression could be used, for example,
to aggregate both B channels in an ISDN connection or
to calculate the percentage hard disk utilization of a
server from the absolute used space and total capac-
ity.
Examples:
Target[myrouter]: 2:public@wellfleetA + 1:public@wellfleetA
Target[myrouter]: 1.3.6.1.4.1.999.1&1.3.6.1.4.1.999.2:public@mydevice /
1.3.6.1.4.1.999.3&1.3.6.1.4.1.999.4:public@mydevice * 100
Note that whitespace must surround each target defini-
tion in the expression. Target definitions themselves
must not contain whitespace, except in interface
descriptions and interface names, where each whites-
pace character is escaped by a backslash.
MRTG automatically rounds the result of the expression
to an integer unless RRDTool logging is in use and the
gauge option is in effect for the target. Internally
MRTG uses Perl's Math::BigFloat package to calculate
the result of the expression with 40 digits of preci-
sion. Even in extreme cases, where, for example, you
take the difference of two 64-bit integers, the result
of the expression should be accurate.
SNMP Request Optimization
MRTG is designed to economize on its SNMP requests.
Where a target definition appears more than once in
the configuration file, MRTG requests the data from
the device only once per round of data collection and
uses the collected data for each instance of a partic-
ular target. Recognition of two target definitions as
being identical is based on a simple string match
rather than any kind of deeper semantic analysis.
Example:
Target[Targ1]: 1:public@CiscoA
Target[Targ2]: 2:public@CiscoA
Target[Targ3]: 1:public@CiscoA + 2:public@CiscoA
Target[Targ4]: 1:public@CISCOA
This results in a total of three SNMP requests. Data
for 1:public@CiscoA and 2:public@CiscoA are requested
only once each, and used for Targ1, Targ2, and Targ3.
Targ4 causes another SNMP request for 1:public@CISCOA,
which is not recognized as being identical to 1:pub-
lic@CiscoA.
MMaaxxBByytteess
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 _M_a_x_B_y_t_e_s is returned, it is
ignored. Also read the section on _A_b_s_M_a_x for further
info. The _M_a_x_B_y_t_e_s value is also used in calculating the
Y range for unscaled graphs (see the section on _U_n_s_c_a_l_e_d).
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, 10 MB Ethernet = 1250000, 100 MB
Ethernet = 12500000. The _M_a_x_B_y_t_e_s 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[myrouter]: 1250000
TTiittllee
Title for the HTML page which gets generated for the
graph.
Example:
Title[myrouter]: Traffic Analysis for Our Nice Company
OOPPTTIIOONNAALL PPEERR TTAARRGGEETT KKEEYYWWOORRDDSS
PPaaggeeTToopp
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 '\n' sequence.
Example:
PageTop[myrouter]:
Traffic Analysis for ETZ C95.1
Our Campus Backbone runs over an FDDI line\n
with a maximum transfer rate of 12.5 megabytes per
Second.
RRoouutteerrUUppttiimmee
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 _R_o_u_t_e_r_U_p_t_i_m_e keyword.
Example:
Target[kacisco.comp.edu]: 1:public@194.64.66.250 + 2:public@194.64.66.250
RouterUptime[kacisco.comp.edu]: public@194.64.66.250
RRoouutteerrNNaammee
If the default name of the router is incorrect/uninforma-
tive, you can use RouterName to specify a different OID on
either the same or a different host.
A practical example: sysName on BayTech DS72 units always
display "ds72", no matter what you set the Unit ID to be.
Instead, the Unit ID is stored at
1.3.6.1.4.1.4779.1.1.3.0, so we can have MRTG display this
instead of sysName.
Example:
RouterName[kacisco.comp.edu]: 1.3.6.1.4.1.4779.1.1.3.0
A different OID on a different host can also be specified:
RouterName[kacisco.comp.edu]: 1.3.6.1.4.1.4779.1.1.3.0:public@194.64.66.251
MMaaxxBByytteess11
Same as MaxBytes, for variable 1.
MMaaxxBByytteess22
Same as MaxBytes, for variable 2.
IIPPvv44OOnnllyy
Many IPv6 routers do not currently support SNMP over IPv6
and must be monitored using IPv4. The IPv4Only option
forces mrtg to use IPv4 when communicating with the tar-
get, even if IPv6 is enabled. This is useful if the target
is a hostname with both IPv4 and IPv6 addresses; without
the IPv4Only keyword, monitoring such a router will not
work if IPv6 is enabled.
If set to no (the default), mrtg will use IPv6 unless the
target has no IPv6 addresses, in which case it will use
IPv4. If set to yes, mrtg will only use IPv4.
Note that if this option is set to yes and the target does
not have an IPv4 address, communication with the target
will fail.
This option has no effect if IPv6 is not enabled.
Example:
Target[v4onlyrouter_1]: 1:public@v4onlyrouter
IPv4Only[v4onlyrouter_1]: Yes
SSnnmmppOOppttiioonnss ((VV33))
SNMPv3 requires a fairly rich set of options. This per-
target keyword allows access to the User Security Model of
SNMPv3. Options are listed in the same syntax as a perl
hash.
_S_e_c_u_r_i_t_y _M_o_d_e_s
SNMPv3 has three security modes, defined on the device
being polled. For example, on Cisco routers the security
mode is defined by the snmp-server group global configura-
tion command.
NoAuthNoPriv
Neither Authentication nor Privacy is defined. Only
the Username option is specified for this mode.
Example:
SnmpOptions[myrouter]: username=>'user1'
AuthNoPriv
Uses a Username and a password. The password can be
hashed using the snmpkey application, or passed in
plain text along with the ContextEngineID
Example:
SnmpOptions[myrouter]: username=>'user1',authpassword=>'example',
contextengineid=>'80000001110000004000000'
Priv
Both Authentication and Privacy is defined. The
default privacy protocol is des.
Example:
SnmpOptions[myrouter]:
authkey=>'0x1e93ab5a396e2af234c8920e61cfe2028072c0e2',
authprotocol=>'sha',privprotocol=>'des',user-
name=>'user1',
privkey=>'0x498d74940c5872ed387201d74b9b25e2'
_s_n_m_p _o_p_t_i_o_n_s
The following option keywords are recognized:
username
The user associated with the User Security Model
contextname
An SNMP agent can define multiple contexts. This key-
word allows them to be polled.
contextengineid
A unique 24-byte string identifying the snmp-agent.
authpassword
The plaintext password for a user in either AuthNoPriv
or Priv mode.
authkey
A md5 or sha hash of the plain-text password, along
with the engineid. Use the snmpkey commandline pro-
gram to generate this hash, or use Net::SNMP::Secu-
rity::USM in a script.
authprotocol {sha|md5}
The hashing algorithm defined on the SNMP client.
Defaults to md5.
privpassword
A plaintext pre-shared key for encrypting snmp packets
in Priv mode.
privkey
A hash of the plain-text pre-shared key, along with
the engineid. Use the snmpkey commandline program to
generate this hash, or use Net::SNMP::Security::USM in
a script.
privprotocol {des|3desede|aescfb128|aescfb192|aescfb256}
Specifies the encryption method defined on the snmp
agent. The default is des.
PPaaggeeFFoooott
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 '\n' sequence.
The material will be added just before the tag for
the generated webpages.
Example:
BodyTag[myrouter]:
AAbbssMMaaxx
If you are monitoring a link which can handle more traffic
than the _M_a_x_B_y_t_e_s value. Eg, a line which uses compression
or some frame relay link, you can use the _A_b_s_M_a_x 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 _A_b_s_M_a_x, rateup
will ignore values higher than _M_a_x_B_y_t_e_s.
Example:
AbsMax[myrouter]: 2500000
UUnnssccaalleedd
By default each graph is scaled vertically to make the
actual data visible even when it is much lower than
_M_a_x_B_y_t_e_s. With the _U_n_s_c_a_l_e_d 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[myrouter]: ym
WWiitthhPPeeaakk
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[myrouter]: ym
SSuupppprreessss
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[myrouter]: y
EExxtteennssiioonn
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[myrouter]: phtml
DDiirreeccttoorryy
By default, mrtg puts all the files that it generates for
each target (the GIFs, the HTML page, the log file, etc.)
in _W_o_r_k_D_i_r.
If the _D_i_r_e_c_t_o_r_y option is specified, the files are
instead put into a directory under _W_o_r_k_D_i_r or Log-, Image-
and HtmlDir). (For example the _D_i_r_e_c_t_o_r_y option below
would cause all the files for a target myrouter to be put
into directory /usr/tardis/pub/www/stats/mrtg/myrouter/ .)
The directory must already exist; mrtg will not create it.
Example:
WorkDir: /usr/tardis/pub/www/stats/mrtg
Directory[myrouter]: myrouter
NOTE: the Directory option must always be 'relative' or
bad things will happen.
CClloonneeddiirreeccttoorryy
If the _D_i_r_e_c_t_o_r_y option is specified, the _C_l_o_n_e_d_i_r_e_c_t_o_r_y
option will copy all the contents of _D_i_r_e_c_t_o_r_y to the
_C_l_o_n_e_d_i_r_e_c_t_o_r_y.
As well as the _D_i_r_e_c_t_o_r_y option requires, the clone direc-
tory must already exist; mrtg will not create it.
Example:
WorkDir: /usr/tardis/pub/www/stats/mrtg
Directory[myrouter]: myrouter
Clonedirectory[myrouter]: myclonedirectory
NOTE: the Clonedirectory option must always be 'relative'
or bad things will happen.
XXSSiizzee aanndd YYSSiizzee
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[myrouter]: 300
YSize[myrouter]: 300
XXZZoooomm aanndd YYZZoooomm
If you want your graphs to have larger pixels, you can
"Zoom" them.
Example:
XZoom[myrouter]: 2.0
YZoom[myrouter]: 2.0
XXSSccaallee aanndd YYSSccaallee
If you want your graphs to be actually scaled use _X_S_c_a_l_e
and _Y_S_c_a_l_e. (Beware: while this works, the results look
ugly (to be frank) so if someone wants to fix this:
patches are welcome.
Example:
XScale[myrouter]: 1.5
YScale[myrouter]: 1.5
YYTTiiccss aanndd YYTTiiccssFFaaccttoorr
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[myrouter]: 7
YTicsFactor[myrouter]: 0.01
FFaaccttoorr
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
SStteepp
Change the default step from 5 * 60 seconds to something
else (I have not tested this much ...)
Example:
Step[myrouter]: 60
PPNNGGTTiittllee
When using rateup for graph generation, this will print
the given title in the graph it generates.
Example:
PNGTitle[myrouter]: WAN Link UK-US
OOppttiioonnss
The _O_p_t_i_o_n_s 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 _C_o_l_o_u_r_s 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 average 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.
derive
If you are using rrdtool as logger/grapher you can use
a third type of data source. Derive is like counter,
except that it is not required to go UP all the time.
It is useful for situations where the change of some
value should be graphed.
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.
printrouter
When using rateup for graph generation, this option
will print the router name in the graph it generates.
This option is overridden by the value of PNGTitle if
one is given
pngdate
When using rateup for graph generation, this option
will print a timestamp in the graph it generates,
including a timezone if one is specified by the 'Time-
zone' parameter.
logscale
The llooggssccaallee option causes rateup to display the data
with the Y axis scaled logarithmically. Doing so
allows the normal traffic to occupy the majority of
the vertical range, while still showing any spikes at
their full height.
llooggssccaallee displays all the available data and will
always produce well-behaved graphs. People often con-
sider a logarithmically scaled graph counterintuitive,
however, and thus hard to interpret.
expscale
The eexxppssccaallee option causes rateup to display the data
with the Y axis scaled exponentially. Doing so empha-
sizes small changes at the top of the scale; this can
be useful when graphing values that fluctuate by a
small amount near the top of the scale, such as line
voltage.
eexxppssccaallee is essentially the inverse of llooggssccaallee.
secondmean
The sseeccoonnddmmeeaann option sets the maximum value on the
graph to the mean of the data greater than the mean of
all data. This produces a graph that focuses more on
the typical data, while clipping large peaks.
Using sseeccoonnddmmeeaann will give a more intutive linearly
scaled graph, but can result in a uselessly high or
low scale in some rare situations (specifically, when
the data includes a large portion of values far from
the actual mean)
If a target includes both llooggssccaallee and sseeccoonnddmmeeaann in
the options, the sseeccoonnddmmeeaann takes precedence.
Example:
Options[myrouter]: growright, bits
kkiilloo
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[myrouter]: 1024
kkMMGG
Change the default multiplier prefixes (,k,M,G,T,P). In
the tag _S_h_o_r_t_L_e_g_e_n_d 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. If you do not want prefixes, just put two con-
secutive commas. If you want to skip a magnitude select
'-' as value.
Example: velocity in nm/s (nanometers per second) dis-
played in nm/h.
ShortLegend[myrouter]: m/h
kMG[myrouter]: n,u,m,,k,M,G,T,P
options[myrouter]: perhour
CCoolloouurrss
The _C_o_l_o_u_r_s 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 _d_o_r_e_l_p_e_r_c_e_n_t options tag a fifth
colour name colour value pair is required:
Col1#RRGGBB,Col2#RRGGBB,Col3#RRGGBB,Col4#RRGGBB,Col5#RRGGBB
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[myrouter]: GREEN#00eb0c,BLUE#1000ff,DARK GREEN#006600,VIOLET#ff00ff
BBaacckkggrroouunndd
With the _B_a_c_k_g_r_o_u_n_d tag you can configure the background
colour of the generated HTML page.
Example:
Background[myrouter]: #a0a0a0a
YYLLeeggeenndd,, SShhoorrttLLeeggeenndd,, LLeeggeenndd[[11223344]]
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[myrouter]: Bits per Second
ShortLegend[myrouter]: b/s
Legend1[myrouter]: Incoming Traffic in Bits per Second
Legend2[myrouter]: Outgoing Traffic in Bits per Second
Legend3[myrouter]: Maximal 5 Minute Incoming Traffic
Legend4[myrouter]: Maximal 5 Minute Outgoing Traffic
LegendI[myrouter]: In:
LegendO[myrouter]: Out:
Note, if _L_e_g_e_n_d_I or _L_e_g_e_n_d_O are set to an empty string
with
LegendO[myrouter]:
The corresponding line below the graph will not be printed
at all.
TTiimmeezzoonnee
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[myrouter]: Japan
The Timezone is the standard timezone of your system, ie
Japan, Hongkong, GMT, GMT+1 etc etc.
WWeeeekkffoorrmmaatt
By default, mrtg (actually rateup) uses the _s_t_r_f_t_i_m_e(3)
'%V' 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 _s_t_r_f_t_i_m_e(3) routine supports it, you can try
another format option. The POSIX '%V' option correspond
to the widely used ISO 8601 week numbering standard. The
week format character should be specified as a single let-
ter; either W, V, or U.
The UNIX version of rateup uses the libc implementation of
strftime. On Windows, the native strftime implementation
does not know about %V. So there we use a different imple-
mentation of strftime that does support %V.
Example:
Weekformat[myrouter]: W
RRRRDDRRoowwCCoouunntt
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[myrouter]: 1600
TTiimmeeSSttrrPPooss
This defines placement of the timestamp string on the
image. Possible values are RU, LU, RL, LL (which stand,
respectively, for RightUpper, LeftUpper, RightLower and
LeftLower corner) and NO (for no timestamp). By default,
no timestamp is placed on the image.
Example:
TimeStrPos[myrouter]: RU
TTiimmeeSSttrrFFmmtt
Using this keyword you may specify format of the timestamp
to be placed on the image (if enabled by the TimeStrPos
keyword). Specified string will be used by the _s_t_r_f_t_i_m_e_(_)
function - see _s_t_r_f_t_i_m_e(3) documentation for conversion
specifiers available on your system. Default format:
%Y-%m-%d %H:%M
Example:
TimeStrFmt[myrouter]: %H:%M:%S
TTHHRREESSHHOOLLDD CCHHEECCKKIINNGG
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:
TThhrreesshhDDiirr ((GGLLOOBBAALL))
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
TThhrreesshhMMiinnII ((PPEERR TTAARRGGEETT))
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.
TThhrreesshhMMaaxxII ((PPEERR TTAARRGGEETT))
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.
TThhrreesshhDDeesscc ((PPEERR TTAARRGGEETT))
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.
TThhrreesshhPPrrooggII ((PPEERR TTAARRGGEETT))
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.
TThhrreesshhPPrrooggOOKKII ((PPEERR TTAARRGGEETT))
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 $router variable
the unbroken threshold value, and the current parameter
value.
TThhrreesshhMMiinnOO,, TThhrreesshhMMaaxxOO,, TThhrreesshhPPrrooggOO,, aanndd TThhrreesshhPPrrooggOOKKOO
These work the same as their *I counterparts, except on
the Output (second) parameter.
_N_o_t_e _t_h_a_t _y_o_u _c_a_n _u_s_e _t_h_e _S_e_t_E_n_v _p_a_r_a_m_e_t_e_r _e_x_p_l_a_i_n_e_d _a_b_o_v_e
_t_o _p_a_s_s _a_d_d_i_t_i_o_n_a_l _i_n_f_o_r_m_a_t_i_o_n _t_o _t_h_e _t_h_r_e_s_h_o_l_d _p_r_o_g_r_a_m_s_.
SSeettEEnnvv
When calling threshold scripts from within your cfg file
you might want to pass some data on to the script. This
can be done with the SetEnv configuration option which
takes a series of environment variable assignments. Note
that the quotes are mandatory. This does not work for
external scripts. It is not possible to set environment
variables per target.
Example:
SetEnv[myrouter]: EMAIL="contact_email@someplace.net"
HOST="www.some_server.net"
PPEERR TTAARRGGEETT DDEEFFAAUULLTT VVAALLUUEESS
PPrree-- aanndd PPoossttffiixx
To save yourself some typing you can define a target
called '^'. The text of every Keyword you define for this
target will be PREPENDED to the corresponding Keyword of
all the targets defined below this line. The same goes for
a Target called '$' 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[^]: NoWhere Unis Traffic Stats
PageTop[$]: Contact Peter Norton if you have any questions
To remove the prepend/append value, specify an empty
value, e.g.:
PageTop[^]:
PageTop[$]:
NNooSSppaacceeCChhaarr
With PREPEND and APPEND (see below) 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 global option _N_o_S_p_a_c_e_C_h_a_r 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
DDeeffaauulltt VVaalluueess
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.somplace.edu
MaxBytes[_]: 8000
Title[myrouter.somplace.edu.2]: Traffic Analysis for myrouter.somplace.edu IF 2
The default _M_a_x_B_y_t_e_s 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.
CCOOMMMMAANNDD LLIINNEE OOPPTTIIOONNSS
----uusseerr _u_s_e_r_n_a_m_e and ----ggrroouupp _g_r_o_u_p_n_a_m_e
Run as the given user and/or group. (Unix Only)
----lloocckk--ffiillee _f_i_l_e_n_a_m_e
Use an alternate lock-file (the default is to use the
configuration-file appended with "_l").
----ccoonnffccaacchhee--ffiillee _f_i_l_e_n_a_m_e
Use an alternate confcache-file (the default is to use
the configuration-file appended with ".ok")
----llooggggiinngg _f_i_l_e_n_a_m_e|eevveennttlloogg
If this is set to writable filename, all output from
mrtg (warnings, debug messages, errors) will go to
_f_i_l_e_n_a_m_e. If you are running on Win32 you can specify
eevveennttlloogg instead of a filename which will send all
error to the windows event log.
NNOOTTEE:: Note, there is no Message DLL for mrtg included
with 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 you go to the mrtg contrib
download area (on the website) you will find the
mrtg-message-dll.zip which does contain such a thing.
----ddaaeemmoonn
Put MRTG into the background, running as a daemon.
This works the same way as the config file option, but
the switch is required for proper FHS operation
(because /var/run is writable only by root)
----ffhhss
Configure all mrtg paths to conform to the FHS speci-
fication; http://www.pathname.com/fhs/
----cchheecckk
Only check the cfg file for errors. Do not do any-
thing.
----ppiidd--ffiillee==ss
Define the name and path of the pid file for mrtg run-
ning as a daemon
----ddeebbuugg==ss
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
coca - confcache operations
fork - forking view
time - some timing info
log - logging of data via rateup or rrdtool
eval - print eval strings before evaluting them
Example:
--debug="cfg,snpo"
EEXXIITT CCOODDEESS
An exit code of 0 indicates that all targets were success-
ful. Generally speaking, most codes greater than 0 indi-
cate that there was an unrecoverable problem. One excep-
tion to this is code 91, which indicates that at least one
of the targets was succesful. A partial listing of the
codes follows:
0: All targets sucessful
2: Config error (can't read, fatal error in config, etc)
17: Another MRTG process is processing config
91: At least one target sucessful
92: No targets were sucessful
EEXXAAMMPPLLEESS
MMiinniimmaall mmrrttgg..ccffgg
WorkDir: /usr/tardis/pub/www/stats/mrtg
Target[r1]: 2:public@myrouter.somplace.edu
MaxBytes[r1]: 8000
Title[r1]: Traffic Analysis ISDN
PageTop[r1]: Stats for our ISDN Line
CCffgg ffoorr sseevveerraall RRoouutteerrss..
WorkDir: /usr/tardis/pub/www/stats/mrtg
Title[^]: Traffic Analysis for
PageTop[^]: Stats for
PageTop[$]: Contact The Chief if you notice anybody
MaxBytes[_]: 8000
Options[_]: growright
Title[isdn]: our ISDN Line
PageTop[isdn]: our ISDN Line
Target[isdn]: 2:public@router.somplace.edu
Title[backb]: our Campus Backbone
PageTop[backb]: our Campus Backbone
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
Target[isdn2]: 3:public@router.somplace.edu
AAUUTTHHOORR
Tobias Oetiker and many contributors
2.14.7 2006-09-06 MRTG-REFERENCE(1)