nv-l

RE: [nv-l] Switch Analyzer and Layer 3 switches

2004-04-23 05:10:59
Subject: RE: [nv-l] Switch Analyzer and Layer 3 switches
From: Oliver Bruchhaeuser <oliver.bruchhaeuser AT de.ibm DOT com>
To: nv-l AT lists.us.ibm DOT com
Date: Fri, 23 Apr 2004 11:03:04 +0200

Chris,

is your switch in the "ovtopodump -X" output?
If not ... what is the value for " Layer 2 OID" in the "ovtopodump -X <switch>" output?
I assume something like ".... (node is a gateway)".
If so ... is your switch in the topo db as a router:
ovtopodump -v <switch> | grep "^DOES IP FORWARDING:"
If so ... does your switch reports this per SNMP:
snmpget <switch> ip.ipForwarding.0

If so .... The actual version of ITSA will not handle Routers as Layer2 devices.

If you cannot disable routing on the device .... only one idea .... have you tried to block snmp access to "ip.ipForwarding.0" with an access list?
You may be able to fool NetView and so ITSA.

Oliver




"Federico Vidal" <fvidal AT tecsystem.com DOT ar>
Sent by: owner-nv-l AT lists.us.ibm DOT com

22.04.2004 17:54
Please respond to
nv-l

To
<nv-l AT lists.us.ibm DOT com>
cc
Subject
RE: [nv-l] Switch Analyzer and Layer 3 switches





Christopher,
 
ONE of the means by which netview determines a device to be a router is if it has the ipforwarding mib value to true (1).
Disabling routing may turn it to false.
 
Have you then tried itsa's importoid command?
 
Federico Vidal
 
 
 -----Mensaje original-----
De:
Christopher J Petrina [mailto:cjp8 AT meadwestvaco DOT com]
Enviado el:
Thursday, April 22, 2004 4:28 PM
Para:
nv-l AT lists.us.ibm DOT com
Asunto:
[nv-l] Switch Analyzer and Layer 3 switches


Greetings all,


The subject is ominous but here is my situation.


We haev some Alcatel 5024's.  These devices by default have some built in routing capabilites.  As such they contain a routing table where populated or not it is still there,  however these devices are trully only being used as a layer2 switch; but Switch Analyzer is not recognizing them as such.  The reason I found out from Magnum is that One of the means by which netview determines a device to be a router is if it contains a routing table.  Well the moment it finds the table ont hese devices it calls it a router and switch analyzer will not attempt to do any layer2 discovery on it.

  My question is, is there a way to override Netviews discovery and force these devices to show as layer2 devices only?  In the oid_to_type this particular device is listed as a HB (Hub Bridge) with no mention of G(gateway).


Thanks

Chris Petrina


________________________________________________________________________
This email has been scanned for all viruses by the MessageLabs SkyScan
service._______________________________________________________________

This electronic message contains information from MeadWestvaco
Corporation or subsidiary companies, which may be confidential,
privileged or otherwise protected from disclosure. The
information is intended to be used solely by the recipient(s)
named. If you are not an intended recipient, be aware that
any review, disclosure, copying, distribution or use of this
transmission or its contents is prohibited. If you have
received this transmission in error, please notify MeadWestvaco
immediately at postmaster AT MeadWestvaco DOT com.
_______________________________________________________________________