Override response data type

[jmannau]

I am using the snmp_exporter to query a Teltonika router. I have successfully connected it and am sporting data.

I am plotting the mSent and mSentToday (which are the number of bytes sent by the router). According to the MIB these values should be Counter64 but from the received values they are signed integers and overflow to negative values.

I have used snmpwalk to query the router and get the following:

Sending 48 bytes to UDP: [192.168.1.1]:161->[0.0.0.0]:41687
0000: 30 2E 02 01  00 04 06 70  75 62 6C 69  63 A1 21 02    0......public.!.
0016: 04 57 99 06  CE 02 01 00  02 01 00 30  13 30 11 06    .W.........0.0..
0032: 0D 2B 06 01  04 01 82 FC  32 02 02 01  15 01 05 00    .+......2.......


Received 52 byte packet from UDP: [192.168.1.1]:161->[0.0.0.0]:41687
0000: 30 32 02 01  00 04 06 70  75 62 6C 69  63 A2 25 02    02.....public.%.
0016: 04 57 99 06  CE 02 01 00  02 01 00 30  17 30 15 06    .W.........0.0..
0032: 0D 2B 06 01  04 01 82 FC  32 02 02 01  16 01 02 04    .+......2.......
0048: 94 80 01 0A                                           ....

TELTONIKA-MIB::mSent.1 = Wrong Type (should be Counter64): INTEGER: -1803550454

From my investigation, the router is responding with a value that is an unsigned integer but provides the incorrect type in the response, leading to the value being read as a signed integer.

Is it possible to force/cast/override the data type so that the value is parsed correctly as an unsigned Counter64?

Cheers!