[afnog] PRTG configuration

[Brian Candler]

On Mon, Dec 12, 2005 at 10:14:09AM +0100, aniams at accesslinkcorp.com wrote:
> 
> hi all, 
> 
> I presently have a comtrend ADSL router on which i would like to monitor 
> inward internet traffic through mrtg.
> I found on the net a freeware windows tool PRTG on www.paessler.com

You are talking about two different things: MRTG and PRTG.

>From the link you gave, PRTG appears to be commercial software. If you want
help configuring it (even for a free trial), I suggest you contact them
directly.

MRTG is free and open-source software: www.mrtg.org. You may be able to find
people on this list who are using it and can help you.

> but when i want to create sensors for the lan port of the router with snmp 
> sensors the message is
> "connected to unknow device"  sorry no mib2 compatible port found. 
> 
> the snmp configuration of the router is
> community :public and read-only
> snmp agent port number:161
> trap: enable for snmpv2
> snmp ip address: lan port IP 

It may be that your router doesn't have SNMP enabled. You can test this
using snmpwalk from the net-snmp package.

Also, use tcpdump and look for SNMP and ICMP traffic: then you can see
whether (a) your traffic grapher is sending SNMP queries, and (b) whether
your target machine is sending back an SNMP response, or an ICMP unreachable
message.

    # tcpdump -i eth0 -n -s 1500 -X udp port 161 or icmp

Oops, I forgot you're using Windoze. Well, you can probably buy some
software which does packet sniffing. There *is* a version of mrtg for
Windows though.

Regards,

Brian.