SNMP OID probe inconsistency

Below is a probe I originally created to gather info about our Xerox copiers, but then pared down to be useful for all our printers. It's very much a work in progress, but it DOES show the actual page count rather than the rate.

<!--
    ca.on.smcdsb.snmp.generic.printer
    Generic Probe to retrieve page counts
    
    Created 2015 Feb 10
    Updated 2015 Feb 19
    by Julian Daniel

    Simcoe Muskoka Catholic District School Board

-->

<header>
    "type"            =    "custom-snmp"
    "package"        =    "ca.on.smcdsb"
    "probe_name"    =    "snmp.generic.printer"
    "human_name"    =    "Generic Printer Page Count SNMP Probe"
    "version"        =    "1.82"
    "address_type"    =    "IP,AT"
    equiv_class        =     "SNMP"
    port_number        =    "161"
</header>

<snmp-device-properties>
    pdutype="get-request"
    nomib2="true"
    maxvars = "10"
</snmp-device-properties>

<description>
\GB\Generic Printer Page Count SNMP Probe\P\

This probe reads values from a printer's basic SNMP probe. 

***SNMPv2 recommended.

The parameters are:

\b\None\p\ No parameters in this version.
</description>

<snmp-device-variables>

    sysName, 1.3.6.1.2.1.1.5.0 , STRING, "Name"
    sysLocation, 1.3.6.1.2.1.1.6.0 , STRING, "Location"

    hrDeviceDescr, 1.3.6.1.2.1.25.3.2.1.3.1 , STRING, "Device Description"
    prtGeneralSerialNumber, 1.3.6.1.2.1.43.5.1.1.17.1 , STRING, "Serial Number"
    prtMarkerLifeCount, 1.3.6.1.2.1.43.10.2.1.4.1.1, Total-value, "Total Impressions"
    
    hrDeviceStatusAll, 1.3.6.1.2.1.25.3.2.1.5.1, INTEGER, "Overall Status"
    
    displayLine1, 1.3.6.1.2.1.43.16.5.1.2.1.1, DEFAULT, "Line 1 of display"
    displayLine2, 1.3.6.1.2.1.43.16.5.1.2.1.2, DEFAULT, "Line 2 of display"
    displayLine3, 1.3.6.1.2.1.43.16.5.1.2.1.3, DEFAULT, "Line 3 of display"
    displayLine4, 1.3.6.1.2.1.43.16.5.1.2.1.4, DEFAULT, "Line 4 of display"

</snmp-device-variables>

<snmp-device-variables-ondemand>
  ifXTable,               .1,                    TABLE,       "Interface Table"
  ifXTable/ifIndex,       IF-MIB::ifIndex,       DEFAULT,     "Index" 
  ifXTable/ifDescr,       IF-MIB::ifDescr,       DEFAULT,     "Description"
  ifXTable/ifName,        IF-MIB::ifName,        DEFAULT,     "Name"   <!-- ifXTable -->
  ifXTable/ifAlias,       IF-MIB::ifAlias,       DEFAULT,     "Alias"  <!-- ifXTable -->
  ifXTable/ifType,        IF-MIB::ifType,        STRING,      "Link Type  "
  ifXTable/ifSpeed,       IF-MIB::ifSpeed,       DEFAULT,     "Link Speed"
  ifXTable/ifHighSpeed,   IF-MIB::ifHighSpeed,   DEFAULT,     "Mbit/sec"
  ifXTable/ifPhysAddress, IF-MIB::ifPhysAddress, HEXADECIMAL, "MAC Address "
  ifXTable/ifOperStatus,  IF-MIB::ifOperStatus,  STRING,      "Opn'l"
  ifXTable/ifAdminStatus, IF-MIB::ifAdminStatus, DEFAULT,     "Admin"
  
  prtInputTable,    1.3.6.1.2.1.43.8.2.1,    TABLE,"Input Tray Table"
  prtInputTable/prtInputIndex,1.3.6.1.2.1.43.8.2.1.1,    DEFAULT,    "Index"
  prtInputTable/prtInputType,1.3.6.1.2.1.43.8.2.1.2,    DEFAULT,    "Type"
  prtInputTable/prtInputCapacityUnit,1.3.6.1.2.1.43.8.2.1.8,    DEFAULT,    "Capacity Unit"
  prtInputTable/prtInputMaxCapacity,1.3.6.1.2.1.43.8.2.1.9,    DEFAULT,    "Max Capacity"
  prtInputTable/prtInputCurrentLevel,1.3.6.1.2.1.43.8.2.1.10,    DEFAULT,    "Current Level"
  prtInputTable/prtInputStatus,1.3.6.1.2.1.43.8.2.1.11,    DEFAULT,    "Status"
  prtInputTable/prtInputMediaName,1.3.6.1.2.1.43.8.2.1.12,    DEFAULT,    "Media Name"
  prtInputTable/prtInputMediaWeight,1.3.6.1.2.1.43.8.2.1.20,    DEFAULT,    "Media Weight"
  prtInputTable/prtInputMediaType,1.3.6.1.2.1.43.8.2.1.21,    DEFAULT,    "Media Type"
  prtInputTable/prtInputMediaColor,1.3.6.1.2.1.43.8.2.1.22,    DEFAULT,    "Media Colour"
  
  prtMarkerSuppliesTable,    1.3.6.1.2.1.43.11.1.1,    TABLE,"Supplies Table"
  prtMarkerSuppliesTable/prtMarkerSuppliesIndex,1.3.6.1.2.1.43.11.1.1.1,    DEFAULT,    "Supplies index"
  prtMarkerSuppliesTable/prtMarkerSuppliesMarkerIndex,1.3.6.1.2.1.43.11.1.1.2,    DEFAULT,    "Marker"
  prtMarkerSuppliesTable/prtMarkerSuppliesColorantIndex,1.3.6.1.2.1.43.11.1.1.3,    DEFAULT,    "Colour"
  prtMarkerSuppliesTable/prtMarkerSuppliesClass,1.3.6.1.2.1.43.11.1.1.4,    DEFAULT,    "Class"
  prtMarkerSuppliesTable/prtMarkerSuppliesType,1.3.6.1.2.1.43.11.1.1.5,    DEFAULT,    "Type"
  prtMarkerSuppliesTable/prtMarkerSuppliesDescription,1.3.6.1.2.1.43.11.1.1.6,    STRING,    "Description"
  prtMarkerSuppliesTable/prtMarkerSuppliesSupplyUnit,1.3.6.1.2.1.43.11.1.1.7,    DEFAULT,    "Supply Unit"
  prtMarkerSuppliesTable/prtMarkerSuppliesMaxCapacity,1.3.6.1.2.1.43.11.1.1.8,    DEFAULT,    "Max Capacity"
  prtMarkerSuppliesTable/prtMarkerSuppliesLevel,1.3.6.1.2.1.43.11.1.1.9,    DEFAULT,    "Current Level"
</snmp-device-variables-ondemand>

<snmp-device-thresholds>
    alarm:         $hrDeviceStatusAll > 3 "Overall Status = DOWN"
    warning:    $hrDeviceStatusAll = 3 "Overall Status = WARNING"
</snmp-device-thresholds>

<snmp-device-display>
\B5\Printer Info\0P\
  \4\       Model:\0\  $hrDeviceDescr
  \4\  Serial Num:\0\  $prtGeneralSerialNumber
  \4\      Status:\0\  ${eval:$hrDeviceStatusAll==2?"running":$hrDeviceStatusAll==3?"warning":$hrDeviceStatusAll==5?"down":$hrDeviceStatusAll}
  \4\  Interfaces:\0\  ${ifXTable:View Interface Table}
  \4\ Print Count:\0\  $prtMarkerLifeCount
\B5\Current Display Messages\0P\
  \4\      Line 1:\0\  $displayLine1
  \4\      Line 2:\0\  $displayLine2
  \4\      Line 3:\0\  $displayLine3
  \4\      Line 4:\0\  $displayLine4
\B5\Consumables\0P\    ${prtMarkerSuppliesTable:View Consumables Table}
\B5\Input Trays\0P\    ${prtInputTable:View Input Trays Table}
</snmp-device-display>

If the probe is using the DEFAULT type for the OID, it will be
converting the Counter32 into rate/second. The rate of change is 0.

The snmpget and snmpwalk commands show the raw value of the Counter32.

If you set the type of the OID to TOTAL-VALUE, you should see the same
value in the probe that you saw from snmpget/snmpwalk.

You will have to write up a custom probe; there is no way to specify a
variable's type as a parameter.

I would advise finding the built-in Single OID viewer probe and making
a modified copy of it. You can find the built-in probes in the
Probes.zip file in the "InterMapper Settings/Probes" directory.
(com.dartware.snmp.oidsingle.txt)
 

So far, so good -- it's returning a value of 7. Yet, if I setup a Single OID Viewer or Basic OID probe with that same OID, I get a return value of 0. To wit:


If the probe is using the DEFAULT type for the OID, it will be
converting the Counter32 into rate/second. The rate of change is 0.

The snmpget and snmpwalk commands show the raw value of the Counter32.

If you set the type of the OID to TOTAL-VALUE, you should see the same
value in the probe that you saw from snmpget/snmpwalk.

Another place where similar behavior can be seen is the Printer-MIB, specifically the object prtMarkerLifeCount, which tracks the total number of pages printed by a printer over its lifetime.

Unless a custom version of the Single OID Viewer probe which uses TOTAL-VALUE (or INTEGER) rather than DEFAULT is used, this value will will normally show up as 0 or a very low number.

A tip-off is that the value is shown as 0 rather than N/A.