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OSPF problem

netbeginner
Level 2
Level 2

Hii,

I am configuring OSPF between two cisco L3 switches 4510 & 4507 (as of now between these switches static routes are confugured). Configured properly but it is not working..checked by removing the static routes.

router ospf 1

network 10.10.10.0 255.255.255.252 0.0.0.3 area 0

network 10.10.10.4 255.255.255.248 0.0.0.7 area 0

Where i am doing mistake pls. guide me.

Regards

30 Replies 30

Harold Ritter
Cisco Employee
Cisco Employee

Sam,

These network statements are invalid. They should use the wild mask bits only (0.0.0.3 and 0.0.0.7) not the subnet mask (255.255.255.252, 255.255.255.248). By using the following wildcard bits (0.0.0.3 and 0.0.0.7) you will include interfaces in the following ranges in area 0:

10.10.10.0-10.10.10.3

10.10.10.0-10.10.10.7

As you can see the second statement covers the first one.

Is your interface between the two devices in this range?

Regards

Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
México móvil: +52 1 55 8312 4915
Cisco México
Paseo de la Reforma 222
Piso 19
Cuauhtémoc, Juárez
Ciudad de México, 06600
México

Hii,

Sorry i have typed wrong configs by mistake. It is actually as:-

router ospf 1

network 10.10.10.4 0.0.0.7 area 0

network 10.10.10.0 0.0.0.3 area 0

network scenerio is like this -===>

Cisco 4507 Switch ---> Cisco 4510 Switch ---> Cisco Router (on which these routes are running for one connectivity, /30 for WAN & /29 for their LAN).

Pls help.

vishwancc
Level 3
Level 3

Hi Net,

Could you elaborate the problem .

Do you mean OSPF routes are not coming to the routing tables in the switches or they are not forming neighbor relationship.

Chao

Vishwa

Hii Vishwa,

Yes u r right,

neither OSPF routes coming to routing table. Not showing neighbor status.

No output after executing command "sh ip ospf neighbor".

regards

Hello Sam,

follow Leo's suggestions about debug;

you may be facing an MTU mismatch issue between the two devices.

Hope to help

Giuseppe

nishantmj
Level 1
Level 1

check whether the subnet mask on both side of links are the same(must for ospf) and try to ping from both ends.If this is successful...check sh log...if something is reflecting...some ospf logs....

Leo Laohoo
Hall of Fame
Hall of Fame

Try debug:

debug ip ospf adj

debug ip ospf events

debug ip ospf hello

Hello all,

OSPF neighbor is now establised between two switches. But still the two routes running for lease lines (10.XX.XX.XX pool, /30 & /28 ) is still not reachable with OSPF after removing static route.

Regards

Hello Sam,

are network ... area commands present for the IP subnets associated to the leased lines?

post a sh ip route 10.x.x.x

May I ask you what change you did to make the two switches to build an OSPF adjacency ?

This can help to make this a complete story.

Hope to help

Giuseppe

Hello,

PLease to avoid any confusion here i an enclosing the scenrio where i am configuring OSPF (Between Cisco Switch"A" & Cisco Switch"B").

Dear Giuseppe :>> I have made modification in network(10.10.1.6 & 10.10.1.5) under OSPF after which neighbor established.

Switch_A(config)#

router ospf 1

network 10.10.1.6 0.0.0.0 area 0

network 10.10.10.0 0.0.0.3 area 0

network 10.10.10.4 0.0.0.7 area 0

Switch_B(config)#

router ospf 1

network 10.10.1.5 0.0.0.0 area 0

network 10.10.10.0 0.0.0.3 area 0

network 10.10.10.4 0.0.0.7 area 0

+++++++++++++++++++++++++

As updated in previous posts, As present there is static route configured on Switch A towards SwitchB and then towards Cisco Router. And as i want to run OSPF between Switch A & Switch B. I am facing the problem with Lease line (WAN & LAN) route reachable when removing static routes after configuring respective networks in OSPF(As shown in above logs).

Please help to fullfill as required.

Hello,

PLease to avoid any confusion here i an enclosing the scenrio where i am configuring OSPF (Between Cisco Switch"A" & Cisco Switch"B").

Dear Giuseppe :>> I have made modification in network(10.10.1.6 & 10.10.1.5) under OSPF after which neighbor established.

Switch_A(config)#

router ospf 1

network 10.10.1.6 0.0.0.0 area 0

network 10.10.10.0 0.0.0.3 area 0

network 10.10.10.4 0.0.0.7 area 0

Switch_B(config)#

router ospf 1

network 10.10.1.5 0.0.0.0 area 0

network 10.10.10.0 0.0.0.3 area 0

network 10.10.10.4 0.0.0.7 area 0

+++++++++++++++++++++++++

As updated in previous posts, As present there is static route configured on Switch A towards SwitchB and then towards Cisco Router. And as i want to run OSPF between Switch A & Switch B. I am facing the problem with Lease line (WAN & LAN) route reachable when removing static routes after configuring respective networks in OSPF(As shown in above logs).

Please help to fullfill as required.

Hello Sam,

you have two options:

a) extend OSPF on 7613 device and have network area commands on it for the wan links ip subnets and for the link C7613 - Switch B.

b) on switch B you leave the static routes but you add

router ospf 1

red static subnets

network ... area commands are effective only for connected interfaces in OSPF.

This is the reason why the solutions are or to extend the ospf domain or to have switch B to inject in OSPF the routes from its own routing table (without removing the static routes)

Hope to help

Giuseppe

Hello Giuseppe,

Option A)--> I want to run OSPF between Switch A & Switch B only. Hence not extending OSPF to Router.

Option B)--> PLease confirm the purpose of this command on Switch B==>

router ospf 1

red static subnets

Simply asking b'coz we have other Static route also on Switch B. Will this command affect them too(i.e those static route which are not advertised under OSPF)..?

Regards

Hello Sam,

option B needs to be refined using a route-map to avoid to redistribute all static routes.

access-list 33 permit 10.10.10.8 0.0.0.3

access-list 33 permit 10.101.10.12 0.0.0.3

route-map selected_routes permit 10

match ip address 33

router ospf 1

red static route-map selected_routes subnets

Adapt access-list 33 to real ip subnets of the wan links that you want to reach from SwitchA.

Hope to help

Giuseppe

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