generator populating OID types differently than net-snmp

[maemigh]

Host operating system: output of uname -a

Linux tesla 3.10.0-1127.el7.x86_64 #1 SMP Tue Feb 18 16:39:12 EST 2020 x86_64 x86_64 x86_64 GNU/Linux

snmp_exporter version: output of snmp_exporter -version

./snmp_exporter -version
snmp_exporter: error: unknown short flag '-v', try --help

What device/snmpwalk OID are you using?

Dell iDRAC 8

If this is a new device, please link to the MIB(s).

iDRAC-SMIv2.mib link

What did you do that produced an error?

Generator sets type of StringType OIDs as OctetString

What did you expect to see?

DisplayString
snmpget shows the value properly
ex:
IDRAC-MIB-SMIv2::systemOSName.0 = STRING: "VMware ESXi"
This seems to happen for all string values

What did you see instead?

generator sets the type as OctetString and output appears as gauge

# HELP systemOSName This attribute defines the name of the operating system that the host is running. - 1.3.6.1.4.1.674.10892.5.1.3.6
# TYPE systemOSName gauge
systemOSName{systemOSName="0x564D776172652045535869"} 1

[brian-brazil]

StringType is an OCTET STRING, this behaviour is correct. If the vendor wanted it to be treated as ASCII, they should have specified that in the MIB.

[maemigh]

Perhaps I have the details wrong. Nevertheless, behavior doesn't appear to be following that of net-snmp

[brian-brazil]

Net-snmp appears to use a heuristic rather than what the MIB says, we follow the MIB - as it wouldn't be correct to do anything else. The MIB says it's a binary string, so we handle it as a binary string.

[brian-brazil]

Closing, as there's no bug here. We're doing exactly what the MIB tells us to.