[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference kali::dewbr

Title:DECbrouter-90T2,-T2A,-T1
Notice:Kits, DOCs, Release notes, SPDs notes 1-10
Moderator:FOUNDR::SHEEHAN
Created:Wed Dec 23 1992
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1313
Total number of notes:4889

1281.0. "RIP question?" by DEKVC::SEUNGJOOSON () Tue Mar 11 1997 02:41

Hello,

I have scanned most of note topics, but couldn't find out any hints.
Could you please explain me at detail what is wrong?

               PC1
                |
           [--------------------------------------]ethernet-A
                         |255.255.255.0(netmask)
                         |165.243.163.6
                     ----------
                     |DBR90(A)|
                     ----------
                         |192.1.1.1
                         |255.255.255.0
                        dsu
                         |
                       56kbps
                         |
                        dsu
                         |
                         |192.1.1.2
                         |255.255.255.0
                     ----------
                     |DBR90(B)|
                     ----------
                         |165.243.164.6
                         |255.255.255.0
              [-----------------------------]ethernet-B
                   |
                  PC2

DBR90s are DECbrouter 90 software version 9.14(1), and DBR90s had used bridge
function for IP network. Recently the customer wanted to use IP routing.
            IP network address of ethernet-A is 165.243.163.0
            IP network address of ethernet-B is 165.243.164.0
Two IP subnetted addresses would be routed via RIP protocol over 56kbps serial
line which is IP network address 192.1.1.0

After above IP assignment, PC1 and PC2 can not talk each other via TCP/IP.
When checking "show ip route" at the DBR90(A), there is NO routing information
received from DBR90(B), and DBR90(B) doesn't have, either.

So I suspect that the IP address assignment may be something wrong; IP address
of ethernet-A and ethernet-B are Class B, and serial line is Class C. And all
netmasks are 255.255.255.0.  Is it valid IP address assignment?

If there is RIP technical problem about IP address assignment, how can i
resolve it. The customer has to be assigned 165.243.163.0, 165.243.164.0, and
192.1.1.0.

Thanks in advance and regards.
SJ.  
T.RTitleUserPersonal
Name
DateLines
1281.1Can't have a discontiguous networkFOUNDR::OUIMETTEZat was Zen, Dis is Dao...Tue Mar 11 1997 17:39109
    	SJ,
    
    The quick fix is going to be to run IP unnumbered on the serial ports:
    
    int s 0
    ip unnumbered e 0
    
    	In RIP, you *cannot* create a "disjoint", or discontiguous classfull 
    network by dividing it with a different network. In this case, you're 
    dividing the class B network 165.243 with a class C network 192.1.1. Rip 
    can't deal with this. In later versions of the IOS, you can run a protocol 
    such as OSPF, and "IP classless", and I believe what you're doing would 
    then work. I've appended an article from the fuzzy search cisco mailing 
    list (http://www.nexial.nl/cgi-bin) which also addresses this... Also check
    out note 1054.
    
    
       BTW, 9.14(1) is the first version of 9.14- if your customer is
    stable, you may want to leave well enough alone, but if not, consider
    upgrading to the latest 9.14 (which is still unsupported, as are all
    variants of 9.14)- see notes 5 &6 for kit locations.
    
    		regards,
    
    -Chuck O.
     NSTG
    
    From [email protected]  Thu May 11 11:35:12 1995
    Received: from lint.cisco.com (lint.cisco.com [171.68.235.77]) by
    spot.Colorado.EDU (8.6.12/8.6.12/CNS-3.6) with ESMTP id LAA01059 for
    <[email protected]>; Thu, 11 May 1995 11:35:11 -0600
    Received: from [171.69.126.160] (sl-chanty-06.cisco.com                  
    [171.69.126.160]) by lint.cisco.com (8.6.10/CISCO.SERVER.1.1) with SMTP
    id KAA25463; Thu, 11 May 1995 10:34:30 -0700
    X-Sender: [email protected]
    Message-Id: <abd7fade010210034dc8@[171.69.126.160]>
    Mime-Version: 1.0
    Content-Type: text/plain; charset="us-ascii"
    Date: Thu, 11 May 1995 13:34:21 -0400
    To: [email protected], [email protected]
    From: [email protected] (Robert Craig)
    Subject: Re: IANA Free Nets (RFC1597) for point-to-point links?
    
    At 21:45 95/5/10, Paul Ferguson wrote:
    >Michael Borowiec ([email protected]) wrote:
    >
    >> I administer a Class-B network with many point-to-point links. The
    Class-B
    >> is subnetted using standard Class-C subnet mask (255.255.255.0). We
    can't
    >> use variable subnetting, as we are using *GASP* RIP as our primary
    routing
    >> protocol, and we don't want to burn a whole subnet for each of our
    point-
    >> to-point links. We're currently using unnumbered IP on the serial
    inter-
    >> faces, but this causes the remote networks to be disjoined from the
    big
    >> picture on our HP OpenView monitor...
    >
    >> It would sure be nice to be able to use one of the free networks
    provided
    >> by the IANA in RFC1597 for these interfaces. We set up the
    following:
    >
    >>                ROUTER-1             ROUTER-2
    >>        |       +------+             +------+      |
    >>        |       |      |             |      |      |
    >>        |-------+e0  s0+-------------+s0  e1+------|
    >>        |     .1|      |.1         .2|      |.1    |
    >>        |       +------+             +------+      |
    >>     128.212.1            192.168.1             128.212.2
    >
    >> Both Ciscos are Model 3000 running (IGS-BFPX) 9.14(4)...
    >> As you can see, we tried to use one of the Free nets for the
    point-to-
    >> point. We added "network 192.168.1" to the "router rip"
    configuration
    >> on both routers, but ROUTER-2 does not advertise the 128.212.2 net
    over
    >> the serial link, nor does ROUTER-1 advertise any of its nets over
    the
    >> serial link. We fell back to using unnumbered IP. I'd like to know
    if I
    >> can, in fact, use a different network for point-to-point links which
    >> seperate subnets on the same Class-B.
    >
    >
    >You violated one of the basic rules of TCP/IP Networking 101;
    >non-contiguous IP networks. You can't plop aanother (foreign)
    >network down in the middle of a larger/contiguous IP network.
    >
    >- paul
    >
    >--
    >_______________________________________________________________________________
    >Paul Ferguson
    >US Sprint                                          tel: 703.689.6828
    >Managed Network Engineering                   internet:
    [email protected]
    >Reston, Virginia  USA                            
    http://www.sprintmrn.com
    
    Unless you're running a routing protocol which sends mask information
    around (like OSPF, integrated IS-IS, or EIGRP).
    
    Robert.