Asynchronous SNMP (ASNMP)
Currently, SNMP discoveries
are executed through get() and getBulk() calls for low volume exchanges,
but it is inefficient when large volumes of data are fetched or when
communicating with remote devices. The ASNMP feature allows you to
process responses more quickly by packing more requests in one SNMP
packet and by handling the code in a faster language. ASNMP is faster
than Synchronous SNMP since requests are fired without waiting for
a response.
In earlier releases, for any ASNMP request failure,
the IP Manager displayed the following error message in the “Description”
field of the pending list (AD_PendingData):
SNMP request timed out or had an error
From IP 8.x onwards, by default, ASNMP_Control (Asynchronous
SNMP requests) was used. The configurable parameter DoNotUseASNMPPattern
in the tpmgr-param.conf file allows you to disable asynchronous requests
only for specific devices by SysOID. Add the list of sysOID entries
for which you can see one of the following or both the error messages
in the “Description” field of the pending list (AD_PendingData) when
an ASNMP error occurs during discovery:
"ASNM-E-ASNMP_SEND_RECEIVE_ERROR-ASNMP request failure: Error when sending or receiving SNMP data for Host '<IP address of the device>' (Maybe bad credentials)." "ASNM-E-ASNMP_SNMP_ERROR-ASNMP request failure: Error <Error Code>: <Error Message> when receiving SNMP Packet from '<IP address of the device, port<port number>"
By looking into the error messages, you will know that
the errors are related to ASNMP. These are usually caused by the device's
inability to process ASNMP requests. Turning ASNMP off for these devices
may resolve the issue. Add the sysOID entries separated by “|”, for
example:
DoNotUseASNMPPattern .1.3.6.1.4.1.9.5.50|.1.3.6.1.4.9.5.44
The and the provides information on how to enable ASNMP and on the
flag which configures the maximum number of OIDs per packet that can
be sent using ASNMP.