尝试使用pysnmp加载自定义MIB文件时出错

Question

To interface with a Cordex of Alpha Technologies, I need to use the SNMP protocol. I've been going through the documentation and examples from pysnmp in order to get some aspects working, and I have particular issues when using external MIB files from alpha technologies. My first test was the following:

from pysnmp.hlapi import *
from pysnmp.smi import builder, view, compiler, rfc1902
from pysnmp import debug
#debug.setLogger(debug.Debug('all'))
debug.setLogger(debug.Debug('msgproc', 'mibbuild'))
mibBuilder = builder.MibBuilder()

mibViewController = view.MibViewController(mibBuilder)
test = ObjectIdentity('SNMPv2-MIB', 'sysDescr').addAsn1MibSource('file:///C:/Users/SLN9000/Repositories/cordex/MIB/@mib@')
test.resolveWithMib(mibViewController)
test.getOid()

when I do this it correctly prints out the correct OID:

>>> ObjectName('1.3.6.1.2.1.1.1')

However, when looking at the debug logs, it seems to be using the compiled MIB files from the pysnmp library instead of the ASN.1 files located in "C:/Users/SLN9000/Repositories/cordex/MIB/@mib@". When I do something similar for the MIB file from Alpha technologies

from pysnmp.hlapi import *
from pysnmp.smi import builder, view, compiler, rfc1902
from pysnmp import debug
#debug.setLogger(debug.Debug('all'))
debug.setLogger(debug.Debug('msgproc', 'mibbuild'))
mibBuilder = builder.MibBuilder()

mibViewController = view.MibViewController(mibBuilder)
test = ObjectIdentity('03409602D__Alpha_System_Controller', 'dcpower', 1).addAsn1MibSource('file:///C:/Users/SLN9000/Repositories/cordex/MIB/')
test.resolveWithMib(mibViewController)
test.getOid()

It fails at the step test.resolveWithMib(mibViewController) with the error

pysnmp.smi.error.MibNotFoundError: 03409602D__Alpha_System_Controller compilation error(s): missing

It's not completely clear to me what I am doing wrong. The MIB file I am using can be downloaded from here . Any help is appreciated!

Answer 1

My current workaround is to manually compile all the MIB files with the mibdump.py tool. Not really scalable, but at least it allows me to continue my work.

Answer 2

It looks like the canonical name of the MIB they ship in 03409602D__Alpha_System_Controller file is AlphaPowerSystem-MIB (from first line of that file). I think you should better rename this file into the canonical name to simplify matters.

Other files in that .zip archive seem to be copies of standard SNMP MIBs. It is okay that pysnmp uses these of its own -- these core MIBs are implementation-specific. Therefore you do not need the rest of the MIBs from that .zip.

Once you are done with the above, you should be able to perform MIB query like this:

test = ObjectIdentity('AlphaPowerSystem-MIB', 'dcpower', 1).addAsn1MibSource('file:///C:/Users/SLN9000/Repositories/cordex/MIB/')

It works with the snmptranslate.py tool which is based on pysnmp:

$ snmptranslate.py -On  AlphaPowerSystem-MIB::dcpower

1.3.6.1.4.1.7309.4