cacti installed - how to graph traffic?

[mr_scary]

I have installed the latest cacti on OpenBSD 3.7. I am mostly interested in graphing network traffic. Can someone provide basic steps to achieve this? I have installed net-snmp but do not have any experience using SNMP protocol. I feel that there are SNMP issues that the cacti docs do not cover.

[mr_scary]

I want to add:

I see "SNMP not in use" on my cacti page.

Also:

# snmpwalk -c public -v 1 localhost
Timeout: No Response from localhost

[rony]

If you want to graph local interface traffic, you need to be running an snmp agent on the box. Then you can set a community and get the interface statistics.

[mr_scary]

I thought net-snmp was my agent? I installed this by OpenBSD package. Here are the SNMP commands available on my system:

snmpbulkget
snmpcheck
snmpdelta
snmpget
snmpinform
snmpset
snmptable
snmptranslate
snmpusm
snmpwalk
snmpbulkwalk
snmpconf
snmpdf
snmpgetnext
snmpnetstat
snmpstatus
snmptest
snmptrap
snmpvacm

Any advice on how to get this thing off the ground?

[rony]

You are looking for snmpd.

[mr_scary]

Allright. I found snmpd. I started it and I see that my system is listening on port 199. I see that cacti still shows "SNMP not in use".

[rony]

Should be port 161...

Also, you need to set the Snmp Community in the device in cacti. It's probably public.

[mr_scary]

It is definitely port 199. My files show this as description:

smux 199/tcp # SNMP Unix Multiplexer

I started the daemon like this:

# snmpd -a -Lf /var/log/snmpd.log

No errors reported in above logfile:

Reconfiguring daemon
NET-SNMP version 5.1.2 restarted

[rony]

smux is not snmp.....

snmp typically response on udp port 161.

I would check your /etc/snmpd.conf and then attempt to start the service.

[mr_scary]

Allright. My box <i>is</i> listening on UDP 161. Now cacti reports "SNMP error". I changed community string in snmpd.conf:

com2sec local localhost test1
com2sec mynetwork 192.168.2.0/24 test2

and use either test1 or test2 in cacti community field with no success.

[jgtm]

You dont need all that com2sec bollox. You do need the following line though.

rocommunity public


Change "public" to whatever to want your community name to be. Then kill -HUP `head -1 /var/run/snmpd.pid` (or wherever OpenBSD has its pid files).

Then try the following command from the same box:

snmpwalk -Of -c public -v 1 localhost .1.3.6.1.4.1

(replacing public with your community name).

snmpwalk -On -c m3and3r -v 1 localhost .1.3.6.1.2.1

will give you the OID numbers instead of the string names.

Use: man snmpcmd

to get the other -O output options. (snmpwalk and the other snmp commands use snmpcmd).

Use...

snmpwalk -Of -c public -v 1 localhost .1.3.6.1.2.1

for the MIB2 snmp database.

[mr_scary]

Thanks for your reply jgtm.

My config file does not mention 'rocommunity' parameter.

The only place where it mentions the term "community" is where I have already quoted earlier.

What it <i>does</i> say about "public" though is that the daemon (?) will respond to a community name of "public" if there is no config file present.

If I remove (rename) the config file and restart the daemon I get this in my log file:

====================
It's unlikely this agent can serve any useful purpose in this state.
Run "snmpconf -g basic_setup" to help you configure the snmpd.conf file for this agent.
NET-SNMP version 5.1.2
====================

Continuing nonetheless with your command,

# snmpwalk -Of -c public -v 1 localhost .1.3.6.1.4.1
Timeout: No Response from localhost

Although this causes text to be appended to my log file:

====================
Connection from 127.0.0.1
Received SNMP packet(s) from 127.0.0.1
Connection from 127.0.0.1
Connection from 127.0.0.1
Connection from 127.0.0.1
Connection from 127.0.0.1
Connection from 127.0.0.1
====================

[jgtm]

I think you should indeed run "snmpconf -g basic_setup" as thats what i did.

Anyway, if it will help. I have attached my snmpd.conf for you.

The version of net-snmp that I use is in my signature.

[jgtm]

You might also want to check out the net-snmp documentation and tutorials at

http://net-snmp.sourceforge.net/

and also download the MIB browser (x86 version) called Getif 2.3.1 from

http://www.wtcs.org/snmp4tpc/getif.htm

so you can then see what info snmpd will be able to give you.