From: Walter Chen (wchen@xxxxxxxxx)
Date: Wed Apr 18 2001 - 16:01:52 GMT-3
Rob,
This is a neat solution, however you could not reach .25.0-.27.0 included in
the .24/22 mask. So you lose 3/4 of your reachability and of course also
make .36-.39 unusable as you already pointed out. So while this solution
dose not break any rules but also did not fully achieve its primary goal
which is to make the .24/22 network reachable from the IGRP side.
-----Original Message-----
From: Alejandro Cadarso [mailto:a.cadarso@uniway-tec.com]
Sent: Wednesday, April 18, 2001 2:19 PM
To: Rob Hopkins
Cc: ccielab@groupstudy.com
Subject: Re: Redistributing OSPF /22 to IGRP /24, same mayor network
Rob,
It's perfect, that's the solution, or at least one of them ( I cant
think in any other ).
Of course there is the limitation you posted:
172.16.37.0 thru 172.16.39.0 are not available any more but that doesn't
breaks any stated rule.
Alejandro
Rob Hopkins wrote:
> come on guys, dont give up so easy...
>
> change the subnet mask on r1 to /22, I know we were always taught subnet
> masks should
> match, but as long as you keep track of what each router "thinks" its
> connected to, it will be alright..
> If R1 needed to have any routes from 172.16.37.0 thru 172.16.39.0 you're
> gonna have bigger problems,
> (unless they are hanging out on your serial port..) but since it wasnt in
> this case..
>
> output follows:
>
>
> 172.16.0.0/24 is subnetted, 3 subnets
> C 172.16.36.0 is directly connected, Serial0
> I 172.16.24.0 [100/8976] via 172.16.35.1, 00:01:56, Serial0
> [100/8976] via 172.16.36.1, 00:00:07, Serial0
> C 172.16.6.0 is directly connected, Loopback100
> r2#
>
>
>
>
> ----- Original Message -----
> From: "Alejandro Cadarso" <a.cadarso@uniway-tec.com>
> To: "Darren Ward" <dward@pla.net.au>; "Walter Chen" <wchen@iloka.com>;
> "ccielab" <ccielab@groupstudy.com>; <lkounkar@uu.net>
> Sent: Wednesday, April 18, 2001 12:37 PM
> Subject: Re: Redistributing OSPF /22 to IGRP /24, same mayor network
>
>
>> Good idea Darren,
>>
>> Perhaps your way could work, the problem is that when I try to put any
>> IP address from the /24's in a loopback I have:
>>
>> >r4(config-if)#ip address 172.16.26.1 255.255.255.0
>> >172.16.26.0 overlaps with Ethernet0
>>
>> This sounds logical because in this case we would have two interfaces in
>> the same /24 network
>>
>> Louie Answer could be better the problem is that I have another OSPF
>> Router in the same mayor network and I'm not allowed to change it.
>>
>> Thanks very much for your help, but I think there is no answer.
>>
>> Alejandro.
>>
>>
>> Darren Ward wrote:
>>
>>> Hows this sound for a silly idea:
>>>
>>> The requirement is to get a /20 into a /24 IGRP domain.
>>> The second requirement is that no static's can be used at all.
>>>
>>> Create a second OSPF process on the redistributing router (ospf 2 for
>>
> arguments
>
>>> sake)
>>> Create one or more loopbacks and put the 4 /24's on it.
>>> Redistribute the ospf 2 into IGRP and IGRP into ospf 1.
>>>
>>> You may need to do some tweaking on the border router, maybe policy
>>
> routing at
>
>>> worst.
>>>
>>> Darren
>>>
>>>
>>> Walter Chen wrote:
>>>
>>>> The "area x range" command won't work in this case because it won't
>>>
> change
>
>>>> the way directly connected networks are redistributed to IGRP. Using
>>>
> static
>
>>>> routes in this case is preferred because you only need four of them.
>>>>
>>>> However, if you were asked to redistribute /20 OSPF into /28 IGRP (in
>>>
> this
>
>>>> case you have to configure 256 static routes!) or you were not allowed
>>>
> to
>
>>>> use static routes, then you could configure a separate major network
>>>
> with a
>
>>>> /24 mask in OSPF domain, say, 192.168.1.0/24 and redistribute it into
>>>
> IGRP.
>
>>>> >From the IGRP router, configure this network to be your
>>>
> default-network to
>
>>>> let you reach the OSPF 172.16.x.x/20 networks.
>>>>
>>>> If you are now allowed to use either static or IGRP default-network,
>>>
> then
>
>>>> you're stuck.
>>>>
>>>> Walter
>>>>
>>>> -----Original Message-----
>>>> From: Michel GASPARD [mailto:mgaspard@cisco.com]
>>>> Sent: Wednesday, April 18, 2001 8:12 AM
>>>> To: Alejandro Cadarso
>>>> Cc: ccielab
>>>> Subject: Re: Redistributing OSPF /22 to IGRP /24, same mayor network
>>>>
>>>> Alejandro,
>>>>
>>>> Did you already tried the "area x range" command?
>>>>
>>>> Regards,
>>>>
>>>> Michel
>>>>
>>>> Alejandro Cadarso wrote:
>>>>
>>>>> I'm playing with the following scenario and was unable to imagine how
>>>>> can I get 172.16.24.0/22 redistributed from ospf to igrp for r2
>>>>> inserting it in its routing table.
>>>>>
>>>>> Any suggestions will be appreciated. Of course neither Default routing
>>>>> nor static are allowed.
>>>>>
>>>>> ospf igrp loop0
>>>>> -------------r1------------------r2----172.16.6.0/24
>>>>>
>>>>> 172.16.24.0/22 172.16.36.0/24
>>>>> **Please read:http://www.groupstudy.com/list/posting.html
>>>>
>>>> **Please read:http://www.groupstudy.com/list/posting.html
>>>> **Please read:http://www.groupstudy.com/list/posting.html
>>>
>>> **Please read:http://www.groupstudy.com/list/posting.html
>>
>> **Please read:http://www.groupstudy.com/list/posting.html
**Please read:http://www.groupstudy.com/list/posting.html
**Please read:http://www.groupstudy.com/list/posting.html
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