=head1 NAME

mrtg-reference - MRTG 2.17.7 configuration reference

=head1 OVERVIEW

The runtime behaviour of MRTG is governed by a configuration file.

Run-of-the-mill configuration files can be generated with B<cfgmaker>.

(Check L<cfgmaker>). But for more elaborate configurations some hand-tuning

is required.

This document describes all the configuration options understood by

the mrtg software.

=head1 SYNTAX

MRTG configuration file syntax follows some simple rules:

=over

=item *

Keywords must start at the beginning of a line.

=item *

Lines which follow a keyword line which start

with a blank are appended to the keyword line

=item *

Empty Lines are ignored

=item *

Lines starting with a # sign are comments.

=item *

You can add other files into the configuration file using

B<Include:> I<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.  The current working directory will be searched

first.

If the included filename contains an asterisk, then this is taken as a

wildcard for zero or more characters, and all matching files are included.

Thus, you can use this statement to include all files in a specified

subdirectory.

Example:

 Include: servers/*.cfg

In this case, you should be very careful that your wildcard pattern does not

find a match relative to the current working directory if you mean it to be

relative to the main config file directory, since the working directory is 

checked for a match first (as with a normal Include directive).  Therefore,

use of something like '*/*' is discouraged.

=back

=head1 GLOBAL KEYWORDS

=head2 WorkDir

WorkDir specifies where the logfiles and the webpages should

be created.

Example:

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

=head1 OPTIONAL GLOBAL KEYWORDS

=head2 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/

=head2 ImageDir

ImageDir specifies the directory where the images live. They

should be under the html directory.

Example:

 Imagedir: /www/mrtg/images

=head2 LogDir

LogDir specifies the directory where the logs are stored.

This need not be under htmldir directive.

Example:

 Logdir: /www/mrtg/logs

=head2 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

=head2 EnableIPv6

When set to yes, IPv6 support is enabled if the required libraries are

present (see the L<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<IPv4Only> per target option for these routers.

IPv6 is disabled by default.

Example:

 EnableIPv6: Yes

=head2 EnableSnmpV3

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

=head2 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

=head2 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:

=over

=item *

The generated HTML page contains the right

information about the calling interval ...

=item *

A META header in the generated HTML page will instruct

caches about the time-to-live of this page .....

=back

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 in the format 

 Interval: MM[:SS]

Down to 1 second. Note though, setting 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. Also note that you must make sure that your

mrtg-rrd Web-frontend can deal with this kind of Interval setting.

=head2 MaxAge

MRTG relies heavily on the real time clock of your computer. 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).

=head2 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

=head2 NoMib2

Normally we ask the SNMP device for 'sysUptime' and 'sysName' 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

=head2 SingleRequest

Some SNMP implementations can not deal with requests asking 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

=head2 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,

 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.

=head2 IconDir

If you want to keep the mrtg icons in someplace other than the

working (or imagedir) directory, use the I<IconDir> variable for

defining the url of the icons directory.

Example:

 IconDir: /mrtgicons/

=head2 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/local/lib/ft100m.mib

=head2 Language

Switch output format to the selected Language (Check the F<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 

russian 

russian1251 

serbian 

slovak 

slovenian 

spanish 

swedish 

turkish 

ukrainian 

Example:

 Language: danish

=head2 LogFormat

Setting LogFormat to 'rrdtool' in your mrtg.cfg file enables rrdtool mode.

In rrdtool mode, mrtg relies on B<rrdtool> to do its logging. See L<mrtg-rrd>.

Example:

 LogFormat: rrdtool

=head2 LibAdd

If you are using rrdtool mode and your B<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 appropriate path.

Example:

 LibAdd: /usr/local/rrdtool/lib/perl/

=head2 PathAdd

If the B<rrdtool> executable can not be found in the normal C<PATH>, you can

use this keyword to add a suitable directory to your path.

Example:

 PathAdd: /usr/local/rrdtool/bin/

=head2 RRDCached

If you are running RRDTool 1.4 or later with B<rrdcached>, then you can 

configure MRTG to take advantage of this for updates, either by using the 

RRDCACHED_ADDRESS environment variable, or by setting the RRDCached keyword 

in the configuration file.  Note that, if both are set, the configuration file

keyword will take precedence.

Only UNIX domain sockets are fully supported prior to RRDTool v1.5, and 

you should note that using RRDCached mode will disable all Threshold checking 

normally done by MRTG.  Appropriate warning messages will be printed if

necessary.

Examples:

 RRDCached: unix:/var/tmp/rrdcached.sock

 RRDCached: localhost:42217

=head2 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 configuration files happens only once on startup, and if the configuration 

file is modified.

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 B<--user=>I<user_name>

and B<--group=>I<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

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.

If the modification date on the configuration file changes during operation,

then MRTG will re-read the configuration on the next polling cycle.  Note that

sub-files which are included from the main configuration do not have their

modification times monitored, only the top-level file is so checked.

=head2 ConversionCode

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 perform 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 warning 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

"MyConversions.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 configuration 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 subroutine 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.

=head2 SendToGraphite

If you want to send a copy of the collected data into a Graphite database in addition

to storing it in the RRDfile, you can provide your Graphite database name/ip and port

number here. 

This requires the Net::Graphite perl module which is available from CPAN.

Examples:

 # If your Graphite receiver is running on the same host as the MRTG daemon and using the default port 

 SendToGraphite: 127.0.0.1,2003

 # If your Graphite receiver is running on 192.168.100.50 port 5000

 SendToGraphite: 192.168.100.50,5000

 # If your Graphite receiver is running on graphite.mydomain.com port 2003

 SendToGraphite: graphite.mydomain.com,2003

Graphite's namespace has a number of restrictions on what characters are 

allowed. The SendToGraphite functionality makes an attempt to convert the MRTG 

target name and, if specified, the Legendi and Legendo values to Graphite namespace

friendly values. Specifically, the following conversion rules apply:

=over

=item *

Underscores in the target_name are converted to periods which are Graphite namespace delimiters.

=item *

Comma characters are not allowed so they are removed.

=item *

The string "m2g" for MRTG to Graphite is prepended onto the Graphite namespace variable.

=back

Example MRTG target to Graphite namespace conversion:

 # Our MRTG target name from mrtg.cfg is as follows

 Target[switch_GigabitEthernet0_5]: \GigabitEthernet0/5:public1@switch:::::2

After the conversion you will end up with these Graphite namespace values

 m2g.switch.gigabitethernet0.5.in

 m2g.switch.gigabitethernet0.5.out

Next is a more complicated example because Legendi and Legendo are in use to denote min and max

voltage values that pertain to some APC UPS SNMP OIDs

 # Target, Legendi, and Legendo are specified in mrtg.cfg as follows

 Target[apc_minmaxline]: 1.3.6.1.4.1.318.1.1.1.3.2.3.0&1.3.6.1.4.1.318.1.1.1.3.2.2.0:public@apc:

 LegendI[apc_minmaxline]: upsAdvInputMinLineVoltage

 LegendO[apc_minmaxline]: upsAdvInputMaxLineVoltage

After the conversion you will end up with these Graphite namespace values

 m2g.apc.minmaxline.upsAdvInputMinLineVoltage

 m2g.apc.minmaxline.upsAdvInputMaxLineVoltage

If you don't see the data showing up in Graphite, chances are there are invalid characters in

the namespace. To debug this, use the DEBUG=qw(log) directive at the top of the MRTG script 

to find out what is happening with the MRTG to Graphite namespace conversion. 

DEBUG=qw(log) will generate some output similar to what appears below

 2016-10-13 06:08:39 -- --log: RRDs::update(/var/www/mrtg/switch/switch_gigabitethernet0_5.rrd, '1476356919:2738746035:2927936327')

 2016-10-13 06:08:39 -- --log: graphite->send(m2g.switch.gigabitethernet0.5.in,2738746035,1476356919)

 2016-10-13 06:08:39 -- --log: graphite->send(m2g.switch.gigabitethernet0.5.out,2927936327,1476356919)

 2016-10-13 06:09:25 -- --log: RRDs::update(/var/www/mrtg/apc/apc_minmaxline.rrd, '1476356965:122:123')

 2016-10-13 06:09:25 -- --log: graphite->send(m2g.apc.minmaxline.upsAdvInputMinLineVoltage,122,1476356965)

 2016-10-13 06:09:25 -- --log: graphite->send(m2g.apc.minmaxline.upsAdvInputMaxLineVoltage,123,1476356965)

If the MRTG log output looks reasonable, then take a look at Graphite's carbon-cache logs.

=head1 PER TARGET CONFIGURATION

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.

=head2 Target

With the I<Target> keyword you tell mrtg what it should

monitor. The I<Target> keyword takes arguments in a wide

range of formats:

=over

=item 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 characters

must be escaped with a "\".

 Target[bla]: 2:stu\ pi\@d@router

=item 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 normal 32 bit.

Example:

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

=item 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 recommended that

cfgmaker be used to generate configurations 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'

=item noHC

Not all routers that support SNMPv2 or SNMPv3 provide the ifHC* counters

on every interface.  The noHC[] per-target keyword signals that the

low-speed counters ifInOctets and ifOutOctets should be queried instead.

cfgmaker will automatically insert this tag if SNMPv2 or SNMPv3 is specified

but the ifHC* counters are unavailable.

Example:

  Target[myrouter]: #Bri0:router1:::::3

  SnmpOptions[myrouter]: username=>'user1'

  noHC[myrouter]: yes

=item 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 "Target"

description. It flips the incoming and outgoing traffic rates.

Example:

 Target[ezci]: -1:public@ezci-ether.domain

=item Explicit OIDs

You can also explicitly define which OID to query by using the

following syntax 'OID_1&OID_2:community@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

=item 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

=item 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

B<WaLK> or if you want a particular entry from the table returned by the walk

you can use B<WaLK>I<x> where I<x> is a number starting from 0 (!).

Example:

  Target[myrouter]: WaLKstrangeOid.1&WaLKstrangeOid.2:public@myrouter

  Target[myrouter]: WaLK3strangeOid.1&WaLK4strangeOid.2:public@myrouter

=item SnmpGetNext

A special case of an snmp object that is only reachable by 'walking' occurs 

when a single snmpgetnext will return the correct value, but snmpwalk fails.  

This may occur with snmp V2 or V3, as the snmpgetbulk method is used in these 

versions. You can get mrtg to use getnext instead of getbulk by prepending the 

OID with the string B<GeTNEXT>.

Example:

  Target[myrouter]: GeTNEXTstrangeOid&GeTNEXTstrangeOid:public@myrouter

=item Counted SNMP Walk

In other situations, an snmpwalk is needed to count rows, but the actual data

is uninteresting.  For example, counting the number of mac-addresses in a CAM 

table, or the number of simultaneous dialup sessions.  You can get MRTG to count 

the number of instances by prepending the OID with the string B<CnTWaLK>.  The 

following will retrieve the number of simultaneous VOIP calls on some routers:

Example:

   Target[myrouter]: CnTWaLK1.3.6.1.4.1.9.10.55.1.1.1.1.3&CnTWaLK1.3.6.1.4.1.9.10.55.1.1.1.1.3:public@myrouter

=item 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 offset, causing MRTG to graphs wrong instances etc.

MRTG supports IP address instead of ifindex in target definition. 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 different OIDs

and/or interface split by '&' delimiter.

You can tell cfgmaker to generate such references with the option

B<--ifref=ip>.

Example:

 Target[myrouter]: /1.2.3.4:public@wellfleet-fddi.domain

 Target[ezci]: -/1.2.3.4:public@ezci-ether.domain

 Target[myrouter]: ifInErrors/1.2.3.4&ifOutErrors/1.2.3.4:public@myrouter

=item 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

B<--ifref=descr>.

Example:

 Target[myrouter]: \My-Interface2:public@wellfleet-fddi.domain

 Target[ezci]: -\My-Interface2:public@ezci-ether.domain

 Target[myrouter]: ifInErrors\My-If2&ifOutErrors\My-If3: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

=item Interface by Name

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

You can tell cfgmaker to generate such references with the option

B<--ifref=name>.

Example:

 Target[myrouter]: #2/11:public@wellfleet-fddi.domain

 Target[ezci]: -#2/11:public@ezci-ether.domain

 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.

=item 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 Physical 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 target 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 identification. 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 B<--ifref=eth>.

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& *BREAK*

            1.3.6.1.2.1.2.2.1.14!0a-00-10-23-44-51:public@myrouter

 Target[myrouter]: ifInErrors!0a-00-10-23-44-51& *BREAK*

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

Join the lines at *BREAK* ...

=item 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 persistent 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

B<--ifref=type>.

Example:

 Target[myrouter]: %13:public@wellfleet-fddi.domain

 Target[ezci]: -%13:public@ezci-ether.domain

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

=item Extended positioning of ifIndex

There are OIDs that contain the interface index at some inner position within

the OID. To use the above mentioned Interface by IP/Description/Name/Type methods 

in the target definition the keyword 'IndexPOS' can be used to indicate the 

position of ifIndex. If 'IndexPOS' is not used the ifIndex will be appended at the

end of the OID.

Example:

 Target[myrouter]: OID.IndexPOS.1/1.2.3.4&OID.IndexPOS.1/1.2.3.4:public@myrouter

Replace OID by your numeric OID.

=item Extended Host Name Syntax