Re: Routing problems..
Stephen Zedalis (tintype@exis.net)
Thu, 29 May 1997 08:21:03 -0400 (EDT)
There is a good reason why this is happening. RIP v1 can only understand
Classes as originally established. Ie. Class, A, B, C. AND to boot, it
has no provision to pass subnet masks in the routing packets. So it has
to way to tell you that it does NOT want the entire Class A. Your
customer will NEVER straighten this out until they either move to another
netblock, you go to static routes, or you use a routing protocol that
is classless and understands variable length subnet masks (VLSM) like
OSPF. You can filter incoming updates based on the customer's SOURCE
address and udp port 520 (a kludge and certainly not a good solution).
You may also be able to "set <interface> routing off" which will turn of
RIP for that interface (not familiar with how this affects frame
subinterfaces). The best solution in this case is to switch to OSPF. The
IRX and Cisco's are both capable of it, and it is fairly easy to set up.
Stephen Zedalis
System Administrator - Exis Net, Inc.
On Wed, 28 May 1997, Irve Towers wrote:
>We have a customer who has connected two Cisco routers and they are RIPing
>38.0.0.0 to us. They have 2 class-C addresses from PSI. They claim they
>cannot turn this off.. Can I ifilter the serial port to block RIP from these
>two Frame Relay attached Cisco serial ports until they square this away?
>They have been unable to determine why the are RIPing the entire class A but
>in the mean time I'd like to block RIP from them.