Toner levels using SNMP

Question

I'm trying to get the toner levels from a Brother MCF-9465CDN using SNMP, in order to ultimately plot them in a graph using Munin. I'm not getting ink levels though.

Although I'm a bit new to SNMP, I assume what I'm trying should be possible.

$ snmpwalk -v 2c -c public a.b.c.d .1.3.6.1.2.1.43.11.1.1.6
iso.3.6.1.2.1.43.11.1.1.6.1.1 = STRING: "Black Toner Cartridge"
iso.3.6.1.2.1.43.11.1.1.6.1.2 = STRING: "Cyan Toner Cartridge"
iso.3.6.1.2.1.43.11.1.1.6.1.3 = STRING: "Magenta Toner Cartridge"
iso.3.6.1.2.1.43.11.1.1.6.1.4 = STRING: "Yellow Toner Cartridge"
iso.3.6.1.2.1.43.11.1.1.6.1.5 = STRING: "Waste Toner Box"
iso.3.6.1.2.1.43.11.1.1.6.1.6 = STRING: "Belt Unit"
iso.3.6.1.2.1.43.11.1.1.6.1.7 = STRING: "Drum Unit"

There are some other fields I'd like to monitor, such as the Drum and Belt pages left, on which I have more success: see the last two entries below. Note that the Toner Cartridges are all reporting "-3", while I'd expect some kind of value I can use there.

$ snmpwalk -v 2c -c public a.b.c.d iso.3.6.1.2.1.43.11.1.1.9.1
iso.3.6.1.2.1.43.11.1.1.9.1.1 = INTEGER: -3
iso.3.6.1.2.1.43.11.1.1.9.1.2 = INTEGER: -3
iso.3.6.1.2.1.43.11.1.1.9.1.3 = INTEGER: -3
iso.3.6.1.2.1.43.11.1.1.9.1.4 = INTEGER: -3
iso.3.6.1.2.1.43.11.1.1.9.1.5 = INTEGER: -3
iso.3.6.1.2.1.43.11.1.1.9.1.6 = INTEGER: 48877
iso.3.6.1.2.1.43.11.1.1.9.1.7 = INTEGER: 15830

The Brother MFC is using the latest firmware version N1.10.

Using the MFC's web page on a.b.c.d I'm able to get an indication (using a bar) with the amount of toner capacity left.

Solution

It turns out that the "-3" return messages are expected. My Brother MFC doesn't return the level of the toner using snmp, but just "full", "almost empty", "empty" or "absent".

See this question/answer on serverfault.