net-snmp

>>>>> On Thu, 10 Oct 2002 18:48:57 -0700, Fong Tsui <f.tsui@...> said:

Fong> Does that mean for the most cases, people will use
Fong> 'mib2c.iterate.conf' for simple table? Why we can't use
Fong> create-dataset if mib data need to get from outside of agent
Fong> (from other processes)? Also, in what situation we need to use
Fong> 'mib2c.array-user.conf'?

They're all choices.  It really depends on each individuals scenario.
the create-data set configuration file is designed to store
information locally.  It simply won't work if it's stored elsewhere.
The array-user is actually similar, but stores things in a different
way (but Robert needs to speak up here about it).  The iterate
routines are designed to access external data.  You now have a choice
of APIs, which appears to have confused some people (sometimes a
choice is a bad thing I guess)

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...

> Does that mean for the most cases,  people will use 'mib2c.iterate.conf'
> for simple table? Why we can't use create-dataset if mib data need to get
> from outside of agent (from other processes)?

Because that's not how it works.

The whole point of the dataset-style set of helpers is that the data is
held completely within the agent.  They're designed specifically for this
mode of operation.

As far as these two alternatives are concerned, I'd say you'd normally
use 'iterate' for external data, and 'create-dataset' for internal data.


>    Also, in what situation we need to use 'mib2c.array-user.conf'? 

Pass.   As I said originally, this is the one that I understand least.
It feels more general purpose than the others, but I haven't yet had a
chance to implement my standard test MIB module using it, so would
hesitate to comment further until I have done so.
   Robert would be the best person to describe this approach.

Dave

PS: Please - no HTML mail.  Thanks!

On Fri, 11 Oct 2002 08:56:10 +0100 Dave Shield <D.T.Shield@...>
wrote:
DS> >    Also, in what situation we need to use 'mib2c.array-user.conf'? 
DS> 
DS>    Robert would be the best person to describe this approach.

The biggest advantages of the array-user conf file:

1) index information (and possibly the data too) is stored in a container,
which is sorted by index. This means it has direct access to the data, and
doesn't need to iterate over the entire dataset to find an object.

2) it attempts to deal with RowStatus colums to allow row-creation/deletion. It
provides some stub functions (*_can_activate, *_can_deactivate) and takes care
of calling these functions to determine if a row can be created, activated
and/or deleted.


It does require that you keep track of indexes for each row in OID form in a
container. Initially it generates a data structure which contains storage for
all the columns in the table, which is useful if your data is all internal to
the agent. However, if you have external data, you can delete most of the items
in the structure and add a pointer to the real data structure.

-- 
Robert Story, NET-SNMP Junkie
<irc://irc.openprojects.net/#net-snmp> <http://www.net-snmp.org/>

You are lost in a twisty maze of little standards, all different.

>>>>> On Fri, 11 Oct 2002 10:32:11 -0400, Robert Story <rstory@...> said:

Robert> The biggest advantages of the array-user conf file:

Functionally, the array-user and create-dataset configuration files
are two different APIs and mechanisms for doing similar things.  They
both store data locally to the agent.

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...

I guess,  we can use mib2c.iterate.conf for create-dataset purpose, right?  

Fong

-----Original Message-----
From: Wes Hardaker [mailto:hardaker@...]
Sent: Thursday, October 10, 2002 10:50 PM
To: Fong Tsui
Cc: 'Dave Shield'; sandhya satyanarayan;
net-snmp-coders@...
Subject: Re: mib2c query


>>>>> On Thu, 10 Oct 2002 18:48:57 -0700, Fong Tsui <f.tsui@...> said:

Fong> Does that mean for the most cases, people will use
Fong> 'mib2c.iterate.conf' for simple table? Why we can't use
Fong> create-dataset if mib data need to get from outside of agent
Fong> (from other processes)? Also, in what situation we need to use
Fong> 'mib2c.array-user.conf'?

They're all choices.  It really depends on each individuals scenario.
the create-data set configuration file is designed to store
information locally.  It simply won't work if it's stored elsewhere.
The array-user is actually similar, but stores things in a different
way (but Robert needs to speak up here about it).  The iterate
routines are designed to access external data.  You now have a choice
of APIs, which appears to have confused some people (sometimes a
choice is a bad thing I guess)

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...

>>>>> On Fri, 11 Oct 2002 09:29:42 -0700, Fong Tsui <f.tsui@...> said:

Fong> I guess, we can use mib2c.iterate.conf for create-dataset
Fong> purpose, right?

I don't really understand the question.  Can the iterate .conf produce
code which is usable to monitor local storage information?  yes.

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...

Thanks. You answered my question. :-) 
By the way, I saw testhandlder.* code under agent/mibgroups/, which includes scalar, table, etc. Are they for example purpose?

Thanks,

Fong


-----Original Message-----
From: Wes Hardaker [mailto:hardaker@...]
Sent: Friday, October 11, 2002 10:11 AM
To: Fong Tsui
Cc: 'Wes Hardaker'; 'Dave Shield'; sandhya satyanarayan;
net-snmp-coders@...
Subject: Re: mib2c query


>>>>> On Fri, 11 Oct 2002 09:29:42 -0700, Fong Tsui <f.tsui@...> said:

Fong> I guess, we can use mib2c.iterate.conf for create-dataset
Fong> purpose, right?

I don't really understand the question.  Can the iterate .conf produce
code which is usable to monitor local storage information?  yes.

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...

>>>>> On Fri, 11 Oct 2002 10:22:24 -0700, Fong Tsui <f.tsui@...> said:

Fong> By the way, I saw testhandlder.* code under agent/mibgroups/,
Fong> which includes scalar, table, etc. Are they for example purpose?

Yes, but other examples can be found in agent/mibgroup/examples/ which
are better written for purposes of examples.  The testhandler.c file
includes examples not in the examples directory (they need to be rewritten).

-- 
Wes Hardaker
Please mail all replies to net-snmp-coders@...