🚀 go-pugleaf

In article <1993Jan21.092755.23543@nobeltech.se> ppan@nobeltech.se (Per Andersson) writes:
>In article <1993Jan15.142317.2091@msus1.msus.edu> mndot@msus1.msus.edu writes:
>>In article <1j72f7INN5pj@gaia.ucs.orst.edu>, leach@OCE.ORST.EDU (Tom Leach) writes:

>>> I've just received a couple of CableTron MiniMMACS with the SNMP board
>>> installed (the NCMM board).  When I fire up snmpwalk (cmu snmp V1.1b) or
>>> SunNet Manager (V1.2 or 2.0), they all report just 1 interface.
>>I believe this is the correct response.  Their is truely only one interface. 
>>It is either the AUI connector or the Fiber connector to your backbone.  I
>>could be wrong on this but it seems to be consistent with the rest of
>>cabletron's equipment and how they report.

>Or, if that is not the answer, perhaps your box doesn't have all ports
>enabled. I've often been tricked by the fact that you have to enable
>new ports from the terminal port when installing new cards in the MMAC.

>/Per

The response of one link up is correct for a cabletron concentrator.
The SNMP links refer to connection of a device to an IP subnetwork.
The Cabletron box probably has but one connection to the IP subnetwork
and thus one IP interface and should only report one link up.

There is some fairly good textual evidence that there was a major
dearth of expertise relating to bridging and repeater/concentrator
devices during the specification of SNMP.

As a consequence, the reporting of information about the status of
interfaces and links at any other layer other than the network layer
is a task which SNMP (and Son of SNMP) serve rather badly.

In the case of Constellation Bridge or Bridge-Router products, a
Network layer interface corresponds to a logical subbridge (which in
the case of a pure bridge is the whole bridge).  The an IP interface
can correspond to multiple MAC port.  A MAC port can itself be a 6 UTP
segment repeater.

If SNMP took cognizance of such not uncommon device and device
combinations, SNMP would specificy PortUp/PortDown and
SegmentUp/SegmentDown in addition to LinkUp/LinkDown traps.


In short, Cabletron is correct and SNMP (and son of SNMP) is
inadequate for common networking environments.

-- 
Joachim Carlo Santos Martillo Ajami

The article represents noone's opinions other than the author's.