====== Snmpd_&_mrtg ======

SNMPD - Simple Network Management Protocol Daemon to respond to SNMP requests
MRTG - Multi Router Traffic Grapher

MRTG uses SNMPD to collect information on the Network Traffic of a Computer/ Router.

===== Setup Network Traffic Monitoring:=====
apt-get some tools and choose defaults:

 apt-get install mrtg
 apt-get install snmpd    <nowiki>//</nowiki>Daemon Storing Data
 apt-get install snmp   <nowiki>//</nowiki>Daemon Collecting Data from various devices/servers

===== SNMPD Config on Client =====
Edit /etc/snmp/snmpd.conf and change the following:
 change: 
 agentAddress  udp:127.0.0.1:161
 to:
 agentAddress udp:161
 
 change:
 rocommunity public  default    -V systemonly
 to:
 # rocommunity public  default    -V systemonly
 
 change: 
 #rocommunity public  localhost
 to:
 rocommunity public  localhost
 
 add:
 rocommunity public ip.address.of.snmp.monitoring.server

<del>
Removing as it was old sarge/etch config
 com2sec paranoid   default         public
 #com2sec readonly  default         public
 #com2sec readwrite default         private
 to:
 <br>
 #com2sec paranoid  default         public
 com2sec  readonly  127.0.0.1       public
 #com2sec readwrite default         private

Edit /etc/default/snmpd and change the following:
 SNMPDOPTS='-Lsd -Lf /dev/null -p /var/run/snmpd.pid 127.0.0.1'
 to
 SNMPDOPTS='-Lsd -Lf /dev/null -p /var/run/snmpd.pid'
</del>

Restart the snmpd server:
 /etc/init.d/snmpd restart

===== MRTG Config on SERVER =====
Edit /etc/mrtg.cfg and add/replace with the following:
 # Global configuration
 WorkDir: /var/www/mrtg
 WriteExpires: Yes
 <br>
 #For every machine
 Target[[name-of-machine]]: 2:public@127.0.0.1
 MaxBytes[[name-of-machine]]: 1250000
 Title[[name-of-machine]]:
 PageTop[[name-of-machine]]:
 <nowiki><TABLE>
 <TR><TD>System:</TD><TD>kartbuilding on phidebian</TD></TR>
 <TR><TD>Maintainer:</TD> <TD>Stephen Burke</TD></TR>   
 <TR><TD>Description:</TD><TD>Debian PC</TD></TR>   
 <TR><TD>Max Speed:</TD><TD>10 Mbits/s</TD></TR>   
 <TR><TD>Ip:</TD><TD>136.201.1.250</TD></TR> 
 </TABLE>
 #Above table html info to be in 1 space.
 </nowiki>

Run mrtg manually a few time to place logs - it will give errors on first 3-5 runs. There is an entry placed in /etc/cron.d for mrtg to take over then.
 ./mrtg -c /etc/mrtg.cfg

In the "Target" line you see the number 2 we found before, and in "MaxBytes" we have set how many bytes the device maximum can transfer (10Mbit * 1000000bit/Mbit / 8byte/bit = 1250000byte).

===== Additional Info and Debugging =====
snmpd listens on ipaddress:161 where 161 is udp. The following iptables firewall rule is needed:
 iptables -A INPUT -p udp --dport 161 -j ACCEPT

**Helpful Info**
To generate an Automatic mrtg config:
 cfgmaker public@ipaddress >> /etc/mrtg.cfg

To check snmb Info:
 snmpwalk -v 1 -OS -c public localhost

Information got from:

http://apt-get.dk/mrts/
<br>
http://www.netadmintools.com/art390.html
<br>
http://myitforum.com/articles/16/view.asp?id=3928
<br>
http://www.debianhelp.co.uk/mrtg.htm

===== SNMP and APC UPSs =====
No final configs have been written. 

snmpwalk on a UPS will not reveal all the information. Try the following to get more information:
 snmpwalk -v 1 -c public  Network_Name_of_UPS .1

Here are the relevant links (rare) which have been found:<br>
https://lists.oetiker.ch/pipermail/mrtg/2005-May/030094.html<br>
http://www.cuddletech.com/articles/snmp/node13.html<br>
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch23_:_Advanced_MRTG_for_Linux<br>
http://www.skolelinux.no/~klaus/sarge/x3579.html<br>