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palula
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Simple Noob Question

Post by palula »

Hello everybody. I Installed Cacti today on a Linux Machine and I have a simples question. I went through a walkthrough install and made possible for Cacti to run.

But I have some questions regarding Cacti & SNMP, and where should Cacti be installed on a network.

First I went through this config within snmpd.conf and was advised to comment this line: com2sec paranoid default public and to uncomment this one: com2sec readonly default public -- and add the the ip address of the server that´s collecting info within my network.

My question is! By putting this line: com2sec readonly xxx.xxx.xxx.xxx public, will the ip address define the machine that is collecting snmp info or will snmp only collect data from this ip address. Because, Cacti is only collecting data from the Localhost machine...

The other thing is. By installing Cacti on a machine that isn´t a router, will I still be able to retrieve data? Because the machine I´m using as the info collecter for Cacti isn´t placed on a strategic place within a network. It behaves as a client´s machine.
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Linegod
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Post by Linegod »

The IP address is the only address that is allowed to access SNMP on that device. So if that is the snmpd.conf for the server that has Cacti on it, put in 127.0.0.1. Otherwise put in the IP of the Cacti Server (to make it simple, just always put in the network accessible IP address of the Cacti Box)

Cacti must be able to access the devices you want to monitor, via IP, on port 161/udp.
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palula
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Post by palula »

I´d like information on what it is. Why is that IP address there?

I found your answer, but can´t understand it: "The IP address is the only address that is allowed to access SNMP on that device." -- Meaning that snmpd will only retrieve snmp information from that ip address. What if I´m on a network and want to retrieve info on other machines on my network?

Like this: I have the cacti server running on 192.168.0.100 and want snmp to retrieve info on 192.168.0.0/255.255.255.0 -- all machine on the network.

And yet, what would happen if I took out the IP?
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Linegod
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Post by Linegod »

Two things:

1. You don't actually _need_ to put in that IP address. It is used to restrict what IPs can talk _to_ a server running the SNMP daemon.

2. Cacti doesn't require the SNMP daemon. It uses the SNMP tools (snmpget, snmpwalk) to talk with devices on the network.
--
Live fast, die young
You're sucking up my bandwidth.

J.P. Pasnak,CD
CCNA, LPIC-1
http://www.warpedsystems.sk.ca
palula
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Post by palula »

For example I just tried adding a new Host -- a Windows machine that runs snmp. When I create the host, I receive this message on the upper left side, below the name of the host.

Ping Results
UDP ping Timed out

What am I doing wrong? I can´t receive any information but localhost.
palula
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Post by palula »

Ok I found something weird.
In my machine that has Cacti installed, when I type:

Code: Select all

snmpwalk -v 1 -c public localhost system
a lot of info appears on the screen.

When I do this pointing to one my NT servers, it shows nothing.

And when i do this pointing to another XP machine, it shows:

Code: Select all

No response from xxx.xxx.xxx.xxx
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gandalf
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Post by gandalf »

All this suggests that the snmp daemon is not running or not configured correctly on those remote machines
R.
palula
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Post by palula »

It´s Working!!!! ;)

The only graphs that don´t appear are these ones I´m sending attached in images. I don´t know why they aren´t being generated but it doesn´t seem to be a big problem.

But I like things in mint condition so... If anyone can explain why this is happening, it would be very appreciated.
Attachments
available disk space.jpg
available disk space.jpg (53.47 KiB) Viewed 2025 times
cpu utilization.jpg
cpu utilization.jpg (52.11 KiB) Viewed 2025 times
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gandalf
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Post by gandalf »

Please see 2nd link of my sig for debugging
R.
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