Re: Mysterious ".0" at the end of SNMP OID in Quagga

Many thanks Fulko for explanation!

Now everything is clear. This also helped me understand what I see when 
doing snmpwalk for example on Cisco devices. They use mentioned table 
and indexes in SNMP.

Best regards,
Jan Janovic

On 20.12.2014 17:15, Fulko Hew wrote:
> On Sat, Dec 20, 2014 at 9:40 AM, Jan Janovic <[email protected]> wrote:
>> Hello net-snmp community,
>>
>> I'm one of the main developers of the new EIGRP routing protocol daemon for
>> Quagga routing suite. As we came to SNMP support implementation, we realized
>> that to correctly get any of the SNMP values using particular OID, you need
>> to add the mysterious ".0" at the end.
>>
>> So for example when I want to get OSPF Router ID, instead of using snmpget
>> 1.3.6.1.2.1.14.1.1, I need to write snmpget 1.3.6.1.2.1.14.1.1.0. The same
>> situation we can see in our fresh implementation in new daemon. So, it looks
>> like there is problem somewhere beyond Quagga, probably in net-snmp
>> libraries.
>>
>> Do anybody know something about this behaviour please? I'm just curious if
>> it's a bug, or a feature :P
> You need to consider the difference between the 'ID' of a variable or column,
> and the specific 'instance' (index) of the variable of column spot in
> the row of a table.
>
> And the full OID that you see/use is composed of the base value, appended with
> the index info.
>
> When its a scalar variable, the instance is always zero.
> When its in a table, its what ever the specific instance of all the
> 'index' components are.
> (normally indexes into table (rows) are never zero) Note that tables can have
> multiple indexes, and non-interger indexes too.
>
> So in your case, the zero tells us this variable is a simple 'one-of' variable,
> and not a row/column slot in a table.
>
> Hope this clears it up.
>
> Fulko
>


------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk
_______________________________________________
Net-snmp-users mailing list
[email protected]
Please see the following page to unsubscribe or change other options:
https://lists.sourceforge.net/lists/listinfo/net-snmp-users