Re: OSPF problem..pls help.

Bottom line: Both OSPF neighbors are required to be in the same area.

Steve Lyons

On Sun, Sep 13, 2009 at 8:20 AM, Mohamed El Henawy <m.henawy_at_link.net>wrote:

> I think Serial0/0/0 is already on another area and due to dynamic FR
> Mapping
> its getting this packet from 1.1.24.2 which is in Area 2 on this interface
> while it should get it on Serial0/1/0
>
>
>
> ----- Original Message ----- From: "Steve Lyons" <charter21p5_at_gmail.com>
> To: "Divin Mathew John" <divinjohn_at_gmail.com>
> Cc: "Naufal Jamal" <naufalccie_at_yahoo.in>; <ccielab_at_groupstudy.com>
> Sent: Sunday, September 13, 2009 4:11 PM
> Subject: Re: OSPF problem..pls help.
>
>
> Good catch. I didn't even notice. :) Check your configuration on both
>> sides. It appears you have a mismatch of area type.
>>
>> router ospf 1
>> log-adjacency-changes
>> network 1.1.4.4 0.0.0.0 area 0 <====== does this match on the other side.
>>
>>
>> Keep in mind the ospf hello packet has an area-id field and if this does
>> not
>> match on both sides then the adjacency will not be formed.
>>
>> Below is an example of packet structure I found searching google:
>>
>> http://routemyworld.com/wp-content/uploads/2008/07/ospf-packet-header.jpg
>>
>> Also here is some reading on why neighbors might not form:
>>
>>
>> http://supportwiki.cisco.com/ViewWiki/index.php/OSPF_routers_do_not_form_neighbor_relationship_due_to_a_mismatch_in_hello_parameters
>>
>> Steve Lyons
>>
>>
>>
>>
>> On Sun, Sep 13, 2009 at 8:56 AM, Divin Mathew John <divinjohn_at_gmail.com
>> >wrote:
>>
>> *Sep 13 11:20:38.243: OSPF: Rcv pkt from 1.1.24.2, Serial0/0/0, area
>>> 0.0.0.0
>>> mismatch area 0.0.0.2 in the header??
>>>
>>>
>>> On Sun, Sep 13, 2009 at 6:19 PM, Steve Lyons <charter21p5_at_gmail.com
>>> >wrote:
>>>
>>> Ping 224.0.0.5 and source it from the ptp interface. Let me know if you
>>>> get
>>>> a response.
>>>>
>>>> Steve Lyons
>>>>
>>>> On Sun, Sep 13, 2009 at 6:16 AM, Naufal Jamal <naufalccie_at_yahoo.in>
>>>> wrote:
>>>>
>>>> > Hi,
>>>> >
>>>> > I have a full-mesh of ospf network but having problems between R4 and
>>>> > R2
>>>> > point-to-point network type .here is the config/debug on both the
>>>> > routers.the
>>>> > neighbourship never comes up.
>>>> >
>>>> >
>>>> > R4
>>>> >
>>>> > interface Serial0/1/0
>>>> > ip address 1.1.24.4 255.255.255.0
>>>> > encapsulation frame-relay
>>>> > ip ospf network point-to-point
>>>> > frame-relay map ip 1.1.24.4 402
>>>> > frame-relay map ip 1.1.24.2 402 broadcast
>>>> > no frame-relay inverse-arp
>>>> > end
>>>> >
>>>> > R4
>>>> >
>>>> > (config-if)#do debug ip ospf ev
>>>> > OSPF events debugging is on
>>>> > R4(config-if)#
>>>> > *Sep 13 11:20:38.131: OSPF: Send hello to 224.0.0.5 area 2 on
>>>> Serial0/1/0
>>>> > from
>>>> > 1
>>>> > .1.24.4
>>>> > *Sep 13 11:20:38.243: OSPF: Rcv pkt from 1.1.24.2, Serial0/0/0, area
>>>> > 0.0.0.0
>>>> > mismatch area 0.0.0.2 in the header
>>>> >
>>>> > sh ip ospf ne
>>>> > Neighbor ID Pri State Dead Time Address
>>>> Interface
>>>> > 1.1.3.3 1 FULL/DROTHER 00:01:51 1.1.100.3
>>>> > Serial0/0/0
>>>> > 1.1.6.6 1 FULL/BDR 00:01:47 1.1.100.6
>>>> > Serial0/0/0
>>>> >
>>>> > router ospf 1
>>>> > log-adjacency-changes
>>>> > network 1.1.4.4 0.0.0.0 area 0
>>>> > network 1.1.24.4 0.0.0.0 area 2
>>>> > network 1.1.100.4 0.0.0.0 area 0
>>>> > neighbor 1.1.100.3
>>>> > neighbor 1.1.100.6
>>>> >
>>>> > R2
>>>> >
>>>> >
>>>> > R2(config-if)#
>>>> > *Mar 1 16:50:33.663: OSPF: Send hello to 224.0.0.5 area 2 on
>>>> > FastEthernet0/0
>>>> > fr
>>>> > om 1.1.26.2
>>>> > *Mar 1 16:50:34.491: OSPF: Rcv hello from 1.1.4.4 area 2 from >
>>>> Serial0/0
>>>> > 1.1.24.
>>>> > 4
>>>> > *Mar 1 16:50:34.491: OSPF: Send immediate hello to nbr 1.1.4.4, src
>>>> > address
>>>> > 1.1
>>>> > .24.4, on Serial0/0
>>>> > *Mar 1 16:50:34.495: OSPF: Send hello to 224.0.0.5 area 2 on >
>>>> Serial0/0
>>>> > from
>>>> > 1.1
>>>> > .24.2
>>>> > *Mar 1 16:50:34.495: OSPF: End o
>>>> > *Mar 1 16:58:55.403: OSPF: Rcv hello from 1.1.6.6 area 2 from
>>>> > FastEthernet0/0
>>>> > 1
>>>> > .1.26.6
>>>> > *Mar 1 16:58:55.403: OSPF: End of hello processing
>>>> > R2(config-if)#
>>>> > R2(config-if)#do
>>>> > *Mar 1 16:58:58.567: OSPF: Send hello to 224.0.0.5 area 2 on >
>>>> Serial0/0
>>>> > from
>>>> > 1.1
>>>> > .24.2
>>>> > R2(config-if)#do u all
>>>> > All possible debugging has been turned off
>>>> > R2(config-if)#do sh ip ospf ne
>>>> > Neighbor ID Pri State Dead Time Address
>>>> Interface
>>>> > 1.1.4.4 0 INIT/ - 00:00:32 1.1.24.4
>>>> Serial0/0
>>>> > 1.1.6.6 1 FULL/BDR 00:00:33 1.1.26.6
>>>> > FastEthernet0/0
>>>> >
>>>> > interface Serial0/0
>>>> > ip address 1.1.24.2 255.255.255.0
>>>> > encapsulation frame-relay
>>>> > ip ospf network point-to-point
>>>> > frame-relay map ip 1.1.24.2 204
>>>> > frame-relay map ip 1.1.24.4 204 broadcast
>>>> > no frame-relay inverse-arp
>>>> > frame-relay lmi-type cisco
>>>> > end
>>>> >
>>>> > router ospf 1
>>>> > log-adjacency-changes
>>>> > network 1.1.2.2 0.0.0.0 area 2
>>>> > network 1.1.24.2 0.0.0.0 area 2
>>>> > network 1.1.26.2 0.0.0.0 area 2
>>>> >
>>>> > neighborship with R3 and R6 is o.k dont understand why it is not comin
>>>> up
>>>> > between R2 and R4 p2p link...
>>>> >
>>>> > Thanks,
>>>> > Naufal
>>>> >
>>>> >
>>>> > See the Web&#39;s breaking stories, chosen by people like you.
>>>> > Check out Yahoo! Buzz. http://in.buzz.yahoo.com/
>>>> >
>>>> >
>>>> > Blogs and organic groups at http://www.ccie.net
>>>> >
>>>> >
>>>> _______________________________________________________________________
>>>> > Subscription information may be found at:
>>>> > http://www.groupstudy.com/list/CCIELab.html
>>>>
>>>>
>>>> Blogs and organic groups at http://www.ccie.net
>>>>
>>>> _______________________________________________________________________
>>>> Subscription information may be found at:
>>>> http://www.groupstudy.com/list/CCIELab.html
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>> --
>>>
>>>
>>> Oscar Wilde <http://www.quotationspage.com/quote/923.html> - "It is
>>> better to have a permanent income than to be fascinating."
>>>
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
>>
>>
>>
>>
>>
>>
>
> --------------------------------------------------------------------------------
>
>
>
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 8.5.409 / Virus Database: 270.13.94/2367 - Release Date: 09/13/09
> 05:50:00

Blogs and organic groups at http://www.ccie.net
Received on Sun Sep 13 2009 - 10:02:22 ART