debian - Cacti not working for SNMP data sources

I installed packages cacti and snmpd on a Debian server. I'm able to display common graphs in Cacti (such as memory usage, load average, logged in users, etc) using the data templates listed as Unix. Now I want to replace these graphs with new ones using SNMP data sources, because I see there is also CPU usage and because it's not excluded I have to manage multiple hosts in the future.

So, I installed snmpd on the machine and left the snmpd.conf as it is. In Cacti, I created three new data sources from SNMP templates for 127.0.0.1 host:

• ucd/net - CPU Usage - Nice


• ucd/net - CPU Usage - System


• ucd/net - CPU Usage - User

Then I created a new graph from template ucd/net - CPU Usage, and select the three data sources in the Graph Item Fields section. Graph is now enabled and running, but empty. No data have been collected.

Under Console -> Devices my SNMP host is listed as up and running:

System:Linux ip-xx-xx-xxx-xxx 3.2.0-23-virtual #36-Ubuntu SMP Tue Apr 10 22:29:03 UTC 2012 x86_64
Uptime: 929267 (0 days, 2 hours, 34 minutes)
Hostname: ip-xx-xx-xxx-xxx
Location: Sitting on the Dock of the Bay
Contact: Me me@example.org

In SNMP Options I left all as it is:

• SNMP Version: Version 1


• SNMP Community: public


• SNMP Timeout: 500 ms


• Maximum OID's Per Get Request: 10

In Console -> Utilities -> Cacti Log I have multiple warning (two for each data source) every 5 minutes:

10/29/2012 01:45:01 PM - CMDPHP: Poller[0] Host[2] DS[18] WARNING: Result from SNMP not valid. Partial Result: U
10/29/2012 01:45:01 PM - CMDPHP: Poller[0] WARNING: SNMP Get Timeout for Host:'127.0.0.1', and OID:'.1.3.6.1.4.1.2021.4.15.0'
10/29/2012 01:45:01 PM - CMDPHP: Poller[0] Host[1] DS[9] WARNING: Result from SNMP not valid. Partial Result: U
10/29/2012 01:45:01 PM - CMDPHP: Poller[0] WARNING: SNMP Get Timeout for Host:'127.0.0.1', and OID:'.1.3.6.1.4.1.2021.11.52.0'
10/29/2012 01:40:01 PM - CMDPHP: Poller[0] Host[2] DS[19] WARNING: Result from SNMP not valid. Partial Result: U
10/29/2012 01:40:01 PM - CMDPHP: Poller[0] WARNING: SNMP Get Timeout for Host:'127.0.0.1', and OID:'.1.3.6.1.4.1.2021.4.6.0' 
[...]

I have the feeling I'm missing something, but I cannot get it...

Answer

Could you try this command (OID is from Cacti log):

SNMPv1:

  $ snmpwalk -Cc -On -v 1 -c public 127.0.0.1 1.3.6.1.4.1.2021.11.52.0

SNMPv2c: Nowadays is very common SNMPv2c as default, so also try.

  $ snmpwalk -Cc -On -v 1 -c public 127.0.0.1 1.3.6.1.4.1.2021.11.52.0

Also, try changing COMMUNITY and/or IP ADDRESS to local network instead loopback.

If you don't get a result like .1.3.6.1.4.1.2021.11.52.0 = Counter32: 250038, then edit /etc/snmp/snmpd.conf adding or decommenting:

rocommunity public  localhost 

And restart snmpd using one of:

/etc/init.d/snmpd restart
service snmpd restart