Showing results for 
Search instead for 
Did you mean: 

OSPF - Requirement

OSPF - Requirement

Contributor II
Create Date: Jan 26 2012 2:52AM

Hi All, my internal LAN topology is 2 x Summit X450a-48t stacked as CORE switches and 2 x Summit x250e-48p as ACCESS switches (phones and desks).

I need to swap out my CORE X450a-48t stack for a different stack made of 4 x250e-24t switches.

I have only come across one problem, that is that the stack I am swapping does not have OSPF functionality - my knowledge of OSPF is limited but I don't know how the network will react if we replace the core switches with some without OSPF.

The area has been set as the VLAN for my WAN but there is also a static route for same.

Can anyone make any sense of that?



(from Chris_Keegan)

Contributor II
Create Date: Jan 27 2012 7:45AM

Hi Prusso,

Sure does, thanks.

I'm going to put some static routes in and swap out tonight - should be fine. If not I will just put the old stack back as I'm not changing the config on it.

Thanks for your help,


(from Chris_Keegan)

Contributor II
Create Date: Jan 27 2012 3:43AM

Hey Keegster

This shows that OSPF is enabled and you have the WAN interface added to OSPF. the "ODR" means that this switch is not the DR or BDR it is "Other" essentially just and interface on the area. As Scott said even though it is on OSPF I am not sure what it is doing accept receiving routes. If you do a show IPR do you see a lot of routes in there learned from OSPF.

It doesn't look to me like you are sending out any routes as there are no other interfaces up. Most of the time you want to add the local VLAN interfaces as passive to OSPF so that you can send them out in the OSPF updates.

Since it doesn't look like you are sending out any updates you could accomplish the same thing by just settng up a default gateway in the swithc to point to your WAN router.

Does that help?


(from Paul_Russo)

Contributor II
Create Date: Jan 26 2012 7:23AM

Sorry, I did format it al nice but it has ignored me.

See attached.


(from Chris_Keegan)

Contributor II
Create Date: Jan 26 2012 7:12AM

Many thanks for your help!

You are probably right, I don't think it is enabled either (see flags below).

The core switch I am on has an "Advanced Edge" licence, when I run "sh ospf interfaces" as you suggest I get the below information. The flags would indicate that it is not enabled, but what does "OFD" under 'State' for my WAN connection mean?

They are the same VLANS as the previous post, I can't be bothered to sanitise them - they don't mean much.

Thanks again.


VLAN IP Address AREA ID Flags Cost State Neighbors
ASA /24 -r-f- 4/A DOWN 0
LABs /16 -r-f- 4/A DOWN 0
DATA /16 -r-f- 4/A DOWN 0
WAN /24 -rif- 5/A ODR 1
iscsi /24 -r-f- 4/A DOWN 0
SERVERS /16 -r-f- 4/A DOWN 0
SIP /16 -r-f- 4/A DOWN 0
TG_Clients /24 -r-f- 4/A DOWN 0
TG_Servers /16 -r-f- 4/A DOWN 0
TSG /16 -r-f- 10/A DOWN 0
VOICE /16 -r-f- 4/A DOWN 0
WIFI_LAN /24 -r-f- 5/A DOWN 0

Flags : f - Interface Forwarding Enabled, i - Interface OSPF Enabled,
n - Multinetted VLAN, p - Passive Interface,
r - Router OSPF Enable,
A - Automatic Cost, C - Configured Cost.

(from Chris_Keegan)