[SNMP4J] discoverAuthoritativeEngineID

[Stath, Paul]

The discoverAuthoritativeEngineID() method return false if SNMP4J is
unable to determine the engine ID of
the device.

Couple of things to check are:

The timeout argument that SNMP4J waits for a response REPORT is in units
of millisecond.
I have seen people think this is in units of second, and be surprised
that they didn't get a response in 3 milliseconds.

Does the device support SNMPv3?  The "probe" GET PDU that SNMP4J sends
to discover the Engine ID is a SNMPv3 PDU.
If the device does not support SNMPv3, it probably simply ignores the
PDU, thus no response and no engine ID discovery.

Lastly, have you turned off the discover engine ID flag in the USM
class?
You would have to explicitly do this, since discovery is turned on by
default.

If you use Wireshark, do you see your code send the GET PDU (probe), and
do you see the device respond with a REPORT PDU?
Is that response returned before your timeout expires?


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> Today's Topics:
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>    1. discoverAuthoritativeEngineID problem (abattiloro at libero.it)
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> Message: 1
> Date: Thu, 10 Jun 2010 17:37:04 +0200 (CEST)
> From: "abattiloro at libero.it" <abattiloro at libero.it>
> Subject: [SNMP4J] discoverAuthoritativeEngineID problem
> To: snmp4j at agentpp.org
> Message-ID: <22076848.3011031276184224431.JavaMail.root at wmail42>
> Content-Type: text/plain;charset="UTF-8"
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> Simple problem: why snmp.discoverAuthoritativeEngineID() returns null
> every
> time?
> 
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