98 lines
3.1 KiB
Markdown
98 lines
3.1 KiB
Markdown
---
|
|
title: "MRTG - fun with 20th century monitoring solution"
|
|
date: 2022-01-15T14:43:04+01:00
|
|
draft: false
|
|
tags:
|
|
- monitoring
|
|
- mrtg
|
|
categories:
|
|
- monitoring
|
|
---
|
|
|
|
> I'm totaly aware there are more modern monitoring solutions (prometheus, icinga2, prtg and other
|
|
hipster stuff) out there. Despite this, I still like MRTG's minimalist approach.
|
|
|
|
|
|
|
|
## (my) setup
|
|
In my configuration MRTG is solely used for *collecting metrics* from various sources.
|
|
MRTG is very flexible where these metrics come from (snmp, curl, scripts ...).
|
|
My current configuration can be found at https://git.br0tkasten.de/br0tkasten/mrtg
|
|
|
|
### backend
|
|
|
|
#### installation
|
|
In [Alpine](https://www.alpinelinux.org), mrtg can be installed with `apk add mrtg`.
|
|
|
|
#### configuration
|
|
Details on mrtg's config can be found in the [projects online documentation](https://oss.oetiker.ch/mrtg).
|
|
You will find my configs in [my git project](https://git.br0tkasten.de/br0tkasten/mrtg/src/branch/master/config).
|
|
|
|
**Example:**
|
|
```
|
|
LoadMIBs: /usr/share/snmp/mibs/UCD-SNMP-MIB.txt
|
|
WorkDir: /var/www/mrtg/rrd
|
|
LogFormat: rrdtool
|
|
|
|
Target[br0tkasten.eth0]: #eth0:oom6faayaTosh0nizoepoonahCohhahy@10.3.0.1:
|
|
Title[br0tkasten.eth0]: [br0tkasten] eth0
|
|
MaxBytes[br0tkasten.eth0]: 4294967295
|
|
```
|
|
|
|
### frontend
|
|
|
|
#### cgi-bin/graph.pl
|
|
A perl script is generating graphs from rrd using templates for each metric.
|
|
|
|
```
|
|
<img alt="br0tkasten.eth0 Traffic Graph" src="/cgi-bin/graph.pl?width=680&height=200&graph=br0tkasten.eth0">
|
|
```
|
|
##### Parameter
|
|
- graph: name of the metric, the script will look for a template with the same name in tmpl/*.tmpl
|
|
- width & height: dimensions of the returned image in pixel
|
|
|
|
|
|
|
|
##### Templates
|
|
For each metric to be displayed you will have to create a template in tmpl/*metric*.tmpl.
|
|
Templates use rrdgraph syntax. More details can be found at [the projects online documentation](https://oss.oetiker.ch/rrdtool/doc/rrdgraph.en.html)
|
|
|
|
**Example: tmpl/br0tkasten.eth0.tmpl**
|
|
```
|
|
-v in/up bps
|
|
-t [br0tkasten] eth0
|
|
--full-size-mode
|
|
--color=BACK#343637
|
|
--color=CANVAS#F0F0F0
|
|
--color=FONT#F0F0F0
|
|
--font=TITLE:12:DejaVu Bold
|
|
DEF:d=/var/www/mrtg/rrd/br0tkasten.eth0.rrd:ds0:AVERAGE
|
|
DEF:u=/var/www/mrtg/rrd/br0tkasten.eth0.rrd:ds1:AVERAGE
|
|
CDEF:down=d,8,*
|
|
CDEF:up=u,-8,*
|
|
AREA:down#CC9A5780:Down
|
|
AREA:up#2EA34960:Up
|
|
LINE1:down#CC9A57
|
|
LINE1:up#2EA349
|
|
LINE1:0#000000
|
|
```
|
|
|
|
#### cgi-bin/details.pl
|
|
Renders tmpl/details.tmpl to display a html page with a bigger version of the graph.
|
|
Using [rrdGraphJs](https://github.com/oetiker/RrdGraphJS) you can interactively zoom and scroll in your graph.
|
|
|
|
|
|
|
|
#### html
|
|
Graphs are embedded in static (and some dynamically generated) html pages.
|
|
I like to keep things simple - so most content is static.
|
|
Examples can be found in [htdocs](https://git.br0tkasten.de/br0tkasten/mrtg/src/branch/master/htdocs/index.html).
|
|
|
|
```
|
|
<div>
|
|
<b>[br0tkasten.de] eth0</b><br/>
|
|
<a href="/cgi-bin/details.pl?graph=br0tkasten.eth0">
|
|
<img alt="br0tkasten.eth0 Traffic Graph" src="/cgi-bin/graph.pl?width=680&height=200&graph=br0tkasten.eth0">
|
|
</a>
|
|
</div>
|
|
``` |