[cacti-user] rrd file shows NaN for data values, but snmpget gathers data successfully

[ntwrkd <nt...@gm...>]

Hello List,
I have successfully created some graphs for a custom application and I
am polling without any problem.
Except for a few hosts.

Let's take a single graph for example, it is free memory and total
memory on two independant machines, machine1 and machine2.

Machine1 only shows data for free memory, and machine2 only shows data
for total memory.
I did an snmpwalk/snmpget on the OID's present in my data templates,
and it works fine!:

[admin1@machine1 ~]$ snmpget -v1 -c public machine1
1.3.6.1.4.1.2008.2800.100.1.1.101.1
RFC1155-SMI::enterprises.2008.2800.100.1.1.101.1 = STRING: "1016"

So it wasn't snmp that was a problem.
Then I checked the rrd file which shows a bunch of NaN's. I can't
figure out why it is returning as NaN on one graph but works on the
other.
Can you please offer some insights into this?

Thank you,
Matt

[admin1@machine1 ~]$ rrdtool dump
/usr/local/cacti/cacti_current/rra/memmax7001_22912.rrd

<!-- Round Robin Database Dump --><rrd> <version> 0003 </version>
        <step> 300 </step> <!-- Seconds -->
        <lastupdate> 1224630312 </lastupdate> <!-- 2008-10-21 16:05:12 PDT -->

        <ds>
                <name> ChMemMax7001 </name>
                <type> GAUGE </type>
                <minimal_heartbeat> 5000 </minimal_heartbeat>
                <min> 0.0000000000e+00 </min>
                <max> NaN </max>

                <!-- PDP Status -->
                <last_ds> UNKN </last_ds>
                <value> 0.0000000000e+00 </value>
                <unknown_sec> 12 </unknown_sec>
        </ds>

<!-- Round Robin Archives -->   <rra>
                <cf> AVERAGE </cf>
                <pdp_per_row> 1 </pdp_per_row> <!-- 300 seconds -->

                <params>
                <xff> 5.0000000000e-01 </xff>
                </params>
                <cdp_prep>
                        <ds>
                        <primary_value> NaN </primary_value>
                        <secondary_value> 0.0000000000e+00 </secondary_value>
                        <value> NaN </value>
                        <unknown_datapoints> 0 </unknown_datapoints>
                        </ds>
                </cdp_prep>
                <database>
                        <!-- 2008-10-19 14:10:00 PDT / 1224450600 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:15:00 PDT / 1224450900 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:20:00 PDT / 1224451200 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:25:00 PDT / 1224451500 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:30:00 PDT / 1224451800 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:35:00 PDT / 1224452100 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:40:00 PDT / 1224452400 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:45:00 PDT / 1224452700 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:50:00 PDT / 1224453000 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 14:55:00 PDT / 1224453300 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:00:00 PDT / 1224453600 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:05:00 PDT / 1224453900 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:10:00 PDT / 1224454200 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:15:00 PDT / 1224454500 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:20:00 PDT / 1224454800 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:25:00 PDT / 1224455100 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:30:00 PDT / 1224455400 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:35:00 PDT / 1224455700 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:40:00 PDT / 1224456000 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:45:00 PDT / 1224456300 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:50:00 PDT / 1224456600 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 15:55:00 PDT / 1224456900 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:00:00 PDT / 1224457200 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:05:00 PDT / 1224457500 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:10:00 PDT / 1224457800 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:15:00 PDT / 1224458100 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:20:00 PDT / 1224458400 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:25:00 PDT / 1224458700 -->
<row><v> NaN </v></row>
                        <!-- 2008-10-19 16:30:00 PDT / 1224459000 -->
<row><v> NaN </v></row>



Any suggestions are appreciated.

Thanks,
Matt