[pysnmp-users] Troubles switching from hlapi synchronous bulkCmd to asyncore equivalent

[Graham H. <gr...@ze...>]

Hi All,

I've a python+pySNMP script querying an agent using the hlapi (synchronous)
api and I want to switch it to using the hlapi.asyncore api instead.

This is with version 4.3.2 and using bulkCmd().


To do this I had to move most of my code into a callback function, create a
cbCtx object to pass in a dict to store the results into and then call the
snmp-engine's transport dispatcher.

I've come across two problems:


   1. Since the hlapi.asyncore version of bulkCmd() does not seem to
   support the "lexicographicMode=False" option, I now get "extra" results
   returned when the data in the asked-for table runs out. Sometimes this
   contains entries for "columns" in the table that I have *not* asked for,
   sometimes it contains "columns" from "rows" in the next table
   2. My callback seems to be called only once per query, so if the table
   is larger than the number of rows that will fit in one response, the code
   does not issue a new request and my results are truncated. My callback does
   not return a value, but if I add a "return True" to the end, it seems to
   loop forever, including many, many, results from beyond the end of the
   asked-for table


Are these well known problems ?

I can't find an example in the pysnmp code (or documentation) for the
hlapi.asyncore version of bulkCmd(). Is this because no-one uses it ?

Would I be better off switching from hlapi bulkCmd() to the "Native SNMP
API" version ?

Regards,

Graham


-- 


*Graham Hudspith      Zeetta Networks Limited*Software Engineer    Engine
Shed, Station Approach,
gr...@ze...    Temple Meads,
                     Bristol,
                     BS1 6QH
                     United Kingdom
                     zeetta.com <http://www.zeetta.com/>