Re: Interface Addr Change & Config Checks.

1998-09-03 11:41:46
Subject: Re: Interface Addr Change & Config Checks.
From: "Joel A. Gerber" <joel.gerber AT USAA DOT COM>
To: nv-l AT lists.tivoli DOT com
Date: Thu, 3 Sep 1998 10:41:46 -0500
We have faced this situation many times when "moving" IP addresses from one
router to another.  It seems to me that NetView should be able to
automatically delete an interface from a router when it does the
configuration poll (demand poll).  The SNMP get of the interfaces table will
show that the interface no longer exists on that router.  Why not delete it
automatically?  Another possible solution is to key off of the "duplicate IP
address" traps that netmon generates when it does the configuration poll on
the router to which the interfaces were moved.  At that point, NetView
should be able to determine which router "owns" the interface, and
automatically delete it from the old one and add it to the new one.  This
kind of processing is very similar to the way NetView handles HSRP
interfaces when there is a HSRP failover, so it seems to me like most of the
function needed is already in the product.  It just need to be integrated to
handle this particular change of "moving" an IP address from one device to

It would be great if the Tivoli-ites/IBMers on the list communicate this to
the appropriate developers, so we do not have to submit product enhancement

        -----Original Message-----
        From:   Michael Seibold PTS/M-SW
        Sent:   Thursday, September 03, 1998 08:34
        Subject:        Re: Interface Addr Change & Config Checks.

        Hi Gary, hi Joe,

        we also have this problem on our V5.1 and we are thinking of opening
        change request on this.

        The problem is even more difficult if you have to move ip-ranges
        one box to another one.

        If you make a demand-poll on a box (say box1) where you took away
        ip-adresses, Netview first checks if these interfaces are still
        responding. When you already moved the ip-adresses to another box
        they are indeed responding (from this box2...) and Netview regards
        as still alive, but on box1!. Later during the demand-poll it
        that the corresponding interface(s) on box1 no longer has an
        but it's not updating his databases, so also the icon for the
        is connected to the wrong box (box1).
        You have to look carefully at "duplicate ip-adress"-events coming
        netview to discover this situation. This trap will be sent by netmon
        when it discovers the ip-adress on box2, which, according to the nv
        database, is still valid on box1.

        Maybe someone from the software developement team at tivoli reads

        Michael Seibold
        debis Systemhaus CCS

        Prokott, Joe wrote:
        > Gary,
        > I agree that I would think this should be done also.  I also want
to ask why
        > wouldn't/shouldn't this occur on NetView for UNIX, as well as the
        > for NT version?  Thanks,
        > Joe Prokott - West Group
        > Network Architect
        > 610 Opperman Drive
        > St. Paul, MN  55123
        > Phone: 651-687-4536
        > Fax: 651-687-6946
        > E-mail: joe.prokott AT westgroup DOT com
        > > -----Original Message-----
        > > From: Boyles, Gary P [SMTP:gary.p.boyles AT INTEL DOT COM]
        > > Sent: Tuesday, September 01, 1998 10:04 AM
        > > To:   NV-L AT UCSBVM.UCSB DOT EDU
        > > Subject:      Interface Addr Change & Config Checks.
        > >
        > > This is a NetView NT question...
        > >
        > > When I change the address of an interface on a router, I can
        > > that the old icon turns red... because NetView doesn't know
        > > the address has been changed, or the interface is down.
        > >
        > > But... once NetView does a configuration check for the router,
        > > it
        > > get rid of the old interface icon, and bring on a new one for
the new
        > > address.
        > >
        > > Shouldn't it do the delete on the old interface icon even if
        > > interface
        > > has been set to unmanaged?
        > >
        > > Obviously, the reason I'm asking is.. that this doesn't always
        > > to be the case.
        > >
        > > Regards,
        > >
        > > Gary Boyles, Intel