Re: Fwd: [ipv6mib] So, where were we?

[Michael MacFaden <mrm@riverstonenet.com>]

On Tue, Oct 08, 2002 at 11:48:01PM +0200, Juergen Schoenwaelder wrote:
>The problem with the IP-FORWARD-MIB is that many systems use
>forwarding bases which are much richer than what the indexing allows
>to report. On such systems, implementing the ipCidrRouteTable (and the
>ipRouteTable) means to report only a subset of the real forwarding
>information. Hence, management applications which try to interpret
>these MIB tables are kind of fooled. This is of course even worse on
>systems that only have ipRouteTable support.

Please decribe a "richer" FIB view.

In my experience, a minimalist standard table for unicast routing provides 
three key values one needs regardless of gateway type/version: 

1) which prefix is installed 
2) who installed it and when  (and this might be optional, but I prefer it)
3) the ip address of the next hop or interface to send to

After that, its all fluff. If one needs more information, 
one should go to a specific routing protocol mib view to see 
additional attributes.

If there are needs for other views of the FIB, then I would suggest
defining additional tables in other rfc documents and get a base
view to full standard asap as appears to be done for rfc2863/2864. 

The SNMPCONF wg has made recommendations in 
http://www.ietf.org/internet-drafts/draft-ietf-snmpconf-bcp-10.txt
section 3.3.6 on this topic. 

>If we really care about interoperable management applications, then we
>need to spell out very clearly that an IP version independent variant
>of the ipCidrRouteTable is only applicable on devices where the
>complete forwarding information can be represented in the
>ipCidrRouteTable. (And it is my understanding that for example a
>recent Linux box would not fit into this category.)

I either don't understand what you are saying or disagree. 
The base management view should be a common minimalist/operational set. 
Should a particular implementation need to display more information
then it can be made available in some other mib module. If less will
work, then we've put too much in. see section 3.1 in the above document.

I believe the current 2096/ipCidrRouteTable contains too much unnecessary
information from an operational standpoint.

Regards,
Mike MacFaden