making graph/templates from scratch

[cacubu]

Hello,

I've been trying to make a graph from scratch so that I can better understand all that's going on with Cacti. I've been successful in:

1) making a Data Template with a Data Input Method of Get SNMP Data followed by the Custom Data OID .1.3.6.1.2.1.2.2.1.11.1.

2) making a Graph Template with the Graph Template Items Area/Average and Gprint/Last.

3) creating a device and then creating a graph based on the Graph Template I created in step 2.

My graph shows in my tree, but I can't figure out why the number I see in my manual snmpget is not the same in my graph? Below are some snmpget/walk commands for reference to my OID.

Thanks!


mysys:~ myuser$ snmpwalk -c cacti-ro -v1 myhost interface
...
IF-MIB::ifInUcastPkts.1 = Counter32: 140830
...


mysys:~ myuser$ snmpwalk -c cacti-ro -v1 -On myhost interface
...
.1.3.6.1.2.1.2.2.1.11.1 = Counter32: 140830
...

mysys:~ myuser$ snmpget -c cacti-ro -v1 myhost .1.3.6.1.2.1.2.2.1.11.1
IF-MIB::ifInUcastPkts.1 = Counter32: 140830

[cacubu]

I've continued to play around with this. I went through the tutorial "Walkthrough: My First..." for udp(InOut)Datagrams and was successful. I've noticed again that the number I see in a manual snmpget is not the same as what I see in my graph (attached). That said, I believe the issue is with my understanding of the number in my snmpget and how that is being read and then graphed by cacti. For example, snmpget for udpIN is (823726) and my graph shows Currrent as (229.42 m). If anyone can explain this to me, I'm all ears! Thanks!

==udpInDatagrams
myuser@mysys:~$ snmpget -c cacti-ro -v1 myhost .1.3.6.1.2.1.7.1.0
iso.3.6.1.2.1.7.1.0 = Counter32: 823726

==udpOutDatagrams
myuser@mysys:~$ snmpget -c cacti-ro -v1 myhost .1.3.6.1.2.1.7.4.0
iso.3.6.1.2.1.7.4.0 = Counter32: 844037

[gandalf]

COUNTER type will be evaluated as
1. a difference to the previous finding
2. the difference will be divided by polling interval (roughly) to get a _rate_
R.

[cacubu]

Hi Gandalf,

Thanks for your reply. I suppose that was pretty obvious, duh . If I do that calculation with the following information, I get 3.0928 datagrams/sec. That sounds right to me and also seems to correlate to what my graphs reads currently (see attached). However, while my graph has the right information it seems the decimal is off 3.0928 vs 316.67. Also, the "m" that shows up following the value, where is that derived from?

Thanks again for your help!

mysys:~ myuser$ snmpwalk -c cacti-ro -v1 myhost udpInDatagrams.0; date
UDP-MIB::udpInDatagrams.0 = Counter32: 852976
Sat Apr 23 12:24:37 MDT 2011

mysys:~ myuser$ snmpwalk -c cacti-ro -v1 myhost udpInDatagrams.0; date
UDP-MIB::udpInDatagrams.0 = Counter32: 853073
Sat Apr 23 12:29:37 MDT 2011

(5*60)/(853073-852976)=3.0928

[cacubu]

For the sake of the thread I'll post this. Pretty sure my answer is with these values in my Graph Template.

Base Value: Whether you want to base the y-axis labels on 1000 or 1024. This field will typically be set to 1024 for memory and 1000 for traffic measurements.

Unit Value: Sets the unit value for the y-axis. You should probably keep the unit short as to keep it readable.

Unit Exponent Value: Sets the 10^e scaling of the y-axis. Valid values for this field are between -18 and 18. For example, you could use 3 to display everything in 'k' (kilo) or -6 to display everything in 'u' (micro).

via: http://docs.cacti.net/manual:087:3_temp ... h_template

[cacubu]

Positive I'm missing something really simple. Thanks again for the help.

[cacubu]

bump.

[noname]

(5*60)/(853073-852976)=3.0928

2. the difference will be divided by polling interval (roughly) to get a _rate_

(853073-852976)/(5*60)=0.32333 (=323.33m)