#31 Negative Integer Values Being Treated as Unsigned Values

[Todd Newton]

I have an OID that is part of a table and is defined as an Integer32 with a valid range from -128 up to 127. However, it appears that SnmpB is interpreting the "-128" as an unsigned value. The MIB definition for one of the OIDs in question is defined as follows:

OBJECT-TYPE
SYNTAX     Integer32 (-128..127)
MAX-ACCESS read-only
STATUS     current

From the "Tree" tab of the SnmpB GUI, the "Node Info" panel for this OID contains the following information:

Composed Type: Integer32
Base Type: INTEGER
Status: current
Access: read-only
Kind: Column
SMI Type: OBJECT-TYPE
Size: 4294967168 .. 127

When performing a GET or a WALK for this OID, the "Query Results" provide the proper responses for negative values. However, when attempting to use SnmpB to plot these values over time, the plotter interprets the values as unsigned values, which throw the plots into the 4.29x10^9 region on the graph, rendering it ineffective for monitoring these specific values over time.