OSPF wildcard

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For OSPF network commands there are plenty of examples in the Lammle book
and Cisco book for nice, neat subnet masks with all 1's in an octet.
255.255.255.0 for example would yield a wildcard of 0.0.0.255.

But what about the network config for a mask like 255.255.255.240 ?  If my
IP address is ..say...170.50.10.17.

Would it be ...network 170.50.10.0 0.0.0.15 area 1

Or...              network 170.50.10.17 0.0.0.15 area 1

Or something else?

Also it seems that you could just use wildcard 0.0.0.0 for all you network
commands and only the wildcard notation for summarization right?  Would that
work on the exam?

Tim




Re: OSPF wildcard


I would say

network 170.50.10.16 0.0.0.15 area 1

because, as the sunben mask is 255.255.255.240, this IP .17 belongs to
10.50.10.16 network *first usable IP is 17)

if the ip was 10.50.10.82 255.255.255.240

network 170.50.10.80 0.0.0.15 area 1


Tayfun



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that




Re: OSPF wildcard


Tim Pope wrote:
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Hi Tim,


If your ip address is 170.50.10.17 and snm is 255.255.255.240, your
network range is

170.50.10.16 through 170.50.10.31 so you would use

network 170.50.10.16 0.0.0.15 area 1


170.50.10.17 is wrong because it is a host address.

170.50.10.0 is wrong because it is a different subnet


The network part of the statement should contain the subnetwork address,
not a host address.

The exam will not allow you to do it any other way.

Bill


Re: OSPF wildcard


This works also:
network 170.50.10.17 0.0.0.0 area 1

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book
my
network
that




Re: OSPF wildcard


Make wrote:
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Yep if you want to only match host 170.50.10.17. If you need to match
170.50.10.17's subnet, it will not work.

Cas..


Re: OSPF wildcard


Actually it works. It adds the network to ospf, not the host. It looks the
right mask from the interface.

viestissä:42ad5a5a$0$80895$e4fe514c@news.xs4all.nl...
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Re: OSPF wildcard


Make wrote:
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Strange...  Is that by design, or a coincidental side effect ?

Just curious...

Cas...


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Re: OSPF wildcard


On Tue, 14 Jun 2005, Cas wrote:

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It's by design.  The network statement indicates which interfaces will
participate in the OSPF processs.  Since you can have only one interface
in a particular subnet on a router, you can specify either the interface
or the subnet.

Doan

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Re: OSPF wildcard


Doan wrote:
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Clear ! Thanks...

Cas.


Re: OSPF wildcard



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By design.

The router realizes what you are trying to do and does it.


Jonathan

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Re: OSPF wildcard



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Yeah, it will.

The router will change it to the correct subnet.



Jonathan




Re: OSPF wildcard


says...
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Router will not change the configuration in this example. The only thing
you're matching here is the interface (which is always /32) and router
will pick up the subnet which is defined on matched interface (in ospf
database), except if that interface is loopback. Then it will pick it as
/32 by default.

--
Ivan

*** User rot13 to see my eMail address ***


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